Croup: Clinical features, evaluation, and diagnosis Author Charles R Woods, MD, MS Section Editors Sheldon L Kaplan, MD Gregory Redding, MD Deputy Editor Carrie Armsby, MD, MPH Disclosures: Charles R Woods, MD, MS Other Financial Interest: Cerexa [Epiglottitis (Data Safety Monitoring Board for pediatric trials of the antibiotic

agent ceftaroline)]. Sheldon L Kaplan, MDGrant/Research/Clinical Trial Support: Pfizer [vaccine (PCV13)]; Forest Lab [antibiotic (Ceftaroline)]; Optimer

[antibiotic (fidaxomicin)]. Consultant/Advisory Boards: Pfizer [vaccine (PCV13)]. Gregory Redding, MD Nothing to disclose. Carrie Armsby, MD,

MPH Nothing to disclose.

Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level

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All topics are updated as new evidence becomes available and our peer review process is complete. Literature review current through: Jul 2015. | This topic last updated: Feb 18, 2015.

INTRODUCTION — Croup is a respiratory illness characterized

by inspiratory stridor, cough, and hoarseness. These symptoms

result from inflammation in the larynx and subglottic airway. A

barking cough is the hallmark of croup among infants and young

children, whereas hoarseness predominates in older children

and adults. Although croup usually is a mild and self-limited

illness, significant upper airway obstruction, respiratory distress,

and, rarely, death, can occur.

The clinical features, evaluation, and diagnosis of croup will be

discussed here. The management of croup is discussed

separately. (See "Croup: Approach to

management" and "Croup: Pharmacologic and supportive

interventions".)

DEFINITIONS — The term croup has been used to describe a

variety of upper respiratory conditions in children, including

laryngitis, laryngotracheitis, laryngotracheobronchitis, bacterial

tracheitis, or spasmodic croup [1]. These terms are defined

below. In the past, the term croup also has been applied to

laryngeal diphtheria (diphtheritic or membranous croup), which

is discussed separately. (See "Epidemiology and

pathophysiology of diphtheria" and "Clinical manifestations,

diagnosis and treatment of diphtheria".)

Throughout this review, the term croup will be used to refer to

laryngotracheitis. Laryngotracheobronchitis,

laryngotracheobronchopneumonitis, bacterial tracheitis, and

spasmodic croup are designated specifically as such.

●Laryngitis refers to inflammation limited to the larynx and

manifests itself as hoarseness [2]. It usually occurs in

older children and adults and, similar to croup, is

frequently caused by a viral infection. The etiology,

management, and evaluation of other causes of

hoarseness are discussed in detail separately.

(See"Hoarseness in children: Etiology and

management" and "Hoarseness in children: Evaluation".)

●Laryngotracheitis (croup) refers to inflammation of the

larynx and trachea [2]. Although lower airway signs are

absent, the typical barking cough will be present.

●Laryngotracheobronchitis (LTB) occurs when

inflammation extends into the bronchi, resulting in lower

airway signs (eg, wheezing, crackles, air trapping,

increased tachypnea) and sometimes more severe illness

than laryngotracheitis alone [2]. This term commonly is

used interchangeably with laryngotracheitis, and the

entities are often indistinct clinically. Further extension of

inflammation into the lower airways results in

laryngotracheobronchopneumonitis, which sometimes

can be complicated by bacterial superinfection. Bacterial

superinfection can be manifest as pneumonia,

bronchopneumonia, or bacterial tracheitis.

●Bacterial tracheitis (also called bacterial croup)

describes bacterial infection of the subglottic trachea,

resulting in a thick, purulent exudate, which causes

symptoms of upper airway obstruction (picture 1). The

bronchi and lungs are typically involved, as well (ie,

bacterial tracheobronchitis). Bacterial tracheitis may occur

as a complication of viral respiratory infections (usually

those which manifest themselves as LTB or

laryngotracheobronchopneumonitis) or as a primary

bacterial infection. (See "Bacterial tracheitis in children:

Clinical features and diagnosis".)

●Spasmodic croup is characterized by the sudden onset

of inspiratory stridor at night, short duration (several

hours), and sudden cessation [2]. This is often in the

setting of a mild upper respiratory infection, but without

fever or inflammation. A striking feature of spasmodic

croup is its recurrent nature, hence the alternate

descriptive term, "frequently recurrent croup". Because of

some clinical overlap with atopic diseases, it is sometimes

referred to as "allergic croup".

We consider "spasmodic croup" to be distinct from

"atypical croup," although the terms are sometimes used

interchangeably. Atypical croup may be defined as

recurrent episodes of croup-like symptoms occurring

beyond the typical age range of six months to three years

for "viral croup" or recurrent episodes that do not appear

to be simple "spasmodic croup" [3].

ETIOLOGY — Croup is usually caused by viruses. Bacterial

infection may occur secondarily, as described above.

Parainfluenza virus type 1 is the most common cause of acute

laryngotracheitis, especially the fall and winter epidemics [4-6].

Parainfluenza type 2 sometimes causes croup outbreaks, but

usually with milder disease than type 1. Parainfluenza type 3

causes sporadic cases of croup that often are more severe than

those due to types 1 and 2. In multicenter surveillance of

children <5 years who were hospitalized with febrile or acute

respiratory illnesses, 43 percent of children with confirmed

parainfluenza infection were diagnosed with croup [7]. Croup

was the most common discharge diagnosis for children with

confirmed parainfluenza 1 (42 percent) and parainfluenza 2 (48

percent) infections but was only diagnosed in 11 percent of

children with confirmed parainfluenza 3 infections.

The microbiology, pathogenesis, and epidemiology of

parainfluenza infections are discussed separately.

(See "Parainfluenza viruses in children".)

A number of other viruses that typically cause lower respiratory

tract disease also can cause upper respiratory tract symptoms,

including croup, as described below [6].

●Respiratory syncytial virus (RSV) and adenoviruses are

relatively frequent causes of croup. The laryngotracheal

component of disease is usually less significant than that

of the lower airways. (See "Respiratory syncytial virus

infection: Clinical features and diagnosis", section on

'Clinical manifestations' and "Epidemiology and clinical

manifestations of adenovirus infection", section on

'Clinical presentation'.)

●Human coronavirus NL63 (HCoV-NL63), first identified

in 2004, has been implicated in croup and other

respiratory illnesses [8-10]. The prevalence of HCoV-

NL63 varies geographically. (See "Coronaviruses",

section on 'Respiratory'.)

●Measles is an important cause of croup in areas where

measles remains prevalent. (See "Clinical manifestations

and diagnosis of measles".)

●Influenza virus is a relatively uncommon cause of croup.

However, children hospitalized with influenzal croup tend

to have longer hospitalization and greater risk of

readmission for relapse of laryngeal symptoms than those

with parainfluenzal croup. (See "Seasonal influenza in

children: Clinical features and diagnosis".)

●Rhinoviruses, enteroviruses (especially Coxsackie types

A9, B4, and B5, and echovirus types 4, 11, and 21), and

herpes simplex virus are occasional causes of sporadic

cases of croup that are usually mild. (See appropriate

topic reviews).

●Metapneumoviruses cause primarily lower respiratory

tract disease similar to RSV, but upper respiratory tract

symptoms have been described in some patients [11].

(See "Human metapneumovirus infections".)

Croup also may be caused by bacteria. Mycoplasma

pneumoniae has been associated with mild cases of croup. In

addition, secondary bacterial infection may occur in children

with laryngotracheitis, laryngotracheobronchitis, or

laryngotracheobronchopneumonitis. The most common

secondary bacterial pathogens include Staphylococcus

aureus, Streptococcus pyogenes, and S. pneumoniae [1].

EPIDEMIOLOGY — Croup most commonly occurs in children 6

to 36 months of age. It is seen in younger infants (as young as

three months) and in preschool children, but it is rare beyond

age six years [1,12]. It is more common in boys, with a

male:female ratio of about 1.4:1 [1,12-14].

Family history of croup is a risk factor for croup and recurrent

croup. In a case-control study, children whose parents had a

history of croup were 3.2 times as likely to have an episode of

croup and 4.1 times as likely to have recurrent croup as children

with no parental history of croup [15]. Parental smoking, a well-

recognized risk factor for respiratory tract infections in children,

does not appear to increase the risk of croup [15,16].

(See "Secondhand smoke exposure: Effects in children",

section on 'Respiratory symptoms and illness'.)

Most cases of croup occur in the fall or early winter, with the

major incidence peaks coinciding with parainfluenza type 1

activity (often in October) and minor peaks occurring during

periods of respiratory syncytial virus or influenza virus activity.

(See "Respiratory syncytial virus infection: Clinical features and

diagnosis", section on 'Seasonality' and "Seasonal influenza in

children: Clinical features and diagnosis", section on 'Influenza

activity'.)

Emergency department (ED) visits for croup are most frequent

between 10:00 PM and 4:00 AM. However, children seen for

croup between noon and 6:00 PM are more likely to be admitted

to the hospital [4,17]. A morning peak between 7:00 AM and

11:00 AM in ED visits for croup also has been noted [14].

Hospital admissions for croup have declined steadily since the

late 1970s. In an analysis of data from the National Hospital

Discharge Surveys from 1979 through 1997, the estimated

number of annual hospitalizations for croup decreased from

48,900 to 33,500 [5]. Estimates of annual hospitalization rates

for croup caused by parainfluenza virus types 1 to 3 from 1994

to 1997 were 0.4 to 1.1 per 1000 children for children younger

than one year and 0.24 to 0.61 per 1000 children for children

between one and four years. Approximately one-half of these

hospitalizations were attributed to parainfluenza type 1.

In a six-year (1999 to 2005) population-based study, 5.6 percent

of children with a diagnosis of croup in the ED required hospital

admission. Among those discharged home, 4.4 percent had a

repeat ED visit within 48 hours [14].

PATHOGENESIS — The viruses that cause croup typically infect

the nasal and pharyngeal mucosal epithelia initially and then

spread locally along the respiratory epithelium to the larynx and

trachea.

The anatomic hallmark of croup is narrowing of the trachea in

the subglottic region. This portion of the trachea is surrounded

by a firm cartilaginous ring such that any inflammation results in

narrowing of the airway. In addition to this "fixed" obstruction,

dynamic obstruction of the extrathoracic trachea below the

cartilaginous ring may occur when the child struggles, cries, or

becomes agitated. The dynamic obstruction occurs as a result

of the combination of high negative pressure in the distal

extrathoracic trachea and the floppiness of the tracheal wall in

children.

Laryngoscopic evaluation of patients during acute

laryngotracheitis shows redness and swelling of the lateral walls

of the trachea. In severe cases, the subglottic airway may be

reduced to a diameter of 1 to 2 mm. In addition to mucosal

edema and swelling, fibrinous exudates and, occasionally,

pseudomembranes can build up on the tracheal surfaces and

contribute to airway narrowing. The vocal cords and laryngeal

tissues also can become swollen, and cord mobility may be

impaired [2,18-20]. Autopsy studies in children with

laryngotracheitis show infiltration of histiocytes, lymphocytes,

plasma cells, and neutrophils into edematous lamina propria,

submucosa, and adventitia of the larynx and trachea [21-23].

In spasmodic croup, findings on direct laryngoscopy

demonstrate noninflammatory edema [18]. This suggests that

there is no direct viral involvement of the tracheal epithelium.

Patients with bacterial tracheitis have a bacterial superinfection

that causes thick pus to develop within the lumen of the

subglottic trachea (picture 1). Ulcerations, pseudomembranes,

and microabscesses of the mucosal surface occur. The

supraglottic tissues usually are normal. (See "Bacterial

tracheitis in children: Clinical features and diagnosis", section

on 'Pathogenesis and pathology'.)

Host factors — Only a small fraction of children with

parainfluenza virus infections develop overt croup. This

suggests that host (or genetic) factors play a role in the

pathogenesis. Host factors that may contribute to the

development of croup include functional or anatomic

susceptibility to upper airway narrowing, variations in immune

response, and predisposition to atopy [14].

Underlying host factors that predispose to clinically significant

narrowing of the upper airway include:

●Anatomic narrowing of the airway, from etiologies such

as subglottic stenosis, laryngeal webs, tracheomalacia,

laryngomalacia, laryngeal clefts, or subglottic

hemangiomas [3]

●Hyperactive airways, perhaps aggravated by atopy or

gastroesophageal reflux, as suggested in some children

with spasmodic croup or recurrent croup [24-26]

●Acquired airway narrowing from respiratory tract

papillomas (human papillomavirus), post-intubation

scarring, or irritation from aspirations associated with

gastroesophageal reflux

The potential role of the immune response was demonstrated in

studies that demonstrated increased production of

parainfluenza virus-specific IgE and increased

lymphoproliferative response to parainfluenza virus antigen, and

diminished histamine-induced suppression of lymphocyte

transformation responses to parainfluenza virus in children with

parainfluenza virus and croup compared with those with

parainfluenza virus without croup [27,28].

CLINICAL PRESENTATION — The clinical presentation of croup

depends upon the specific croup syndrome and the degree of

upper airway obstruction. Although croup usually is a mild and

self-limited illness, specific features of the history and physical

examination identify children who are seriously ill or at risk for

rapid progression of disease. (See 'Evaluation' below.)

Laryngotracheitis — Laryngotracheitis typically occurs in children

three months to three years of age [2]. The onset of symptoms

is usually gradual, beginning with nasal irritation, congestion,

and coryza. Symptoms generally progress over 12 to 48 hours

to include fever, hoarseness, barking cough, and stridor.

Respiratory distress increases as upper airway obstruction

becomes more severe. Rapid progression or signs of lower

airway involvement suggests a more serious illness. Cough

usually resolves within three days [29]; other symptoms may

persist for seven days with a gradual return to normal [2].

Deviations from this expected course should prompt

consideration of diagnoses other than laryngotracheitis.

(See 'Differential diagnosis' below.)

The degree of upper airway obstruction is evident on physical

examination, as described below. In mild cases, the child is

hoarse and has nasal congestion. There is minimal, if any,

pharyngitis. As airway obstruction progresses, stridor develops,

and there may be mild tachypnea with a prolonged inspiratory

phase. The presence of stridor is a key element in the

assessment of severity. Stridor at rest is a sign of significant

upper airway obstruction. As upper airway obstruction

progresses, the child may become restless or anxious.

(See 'Severity assessment' below.)

When airway obstruction becomes severe, suprasternal,

subcostal, and intercostal retractions may be seen. Breath

sounds can be diminished. Agitation, which generally is

accompanied by increased inspiratory effort, exacerbates the

subglottic narrowing by creating negative pressure in the

airway. This can lead to further respiratory distress and

agitation.

Hypoxia and cyanosis can develop, as can respiratory fatigue

from sustained increased respiratory effort. High respiratory

rates also tend to correlate with the presence of hypoxia.

Without intervention, the hypoxia or fatigue can sometimes lead

to death.

Spasmodic croup — Spasmodic croup also occurs in children

three months to three years of age [2]. In contrast to

laryngotracheitis, spasmodic croup always occurs at night; the

duration of symptoms is short, often with symptoms subsiding

by the time of presentation for medical attention; and the onset

and cessation of symptoms are abrupt. Fever is typically

absent, but mild upper respiratory tract symptoms (eg, coryza)

may be present. Episodes can recur within the same night and

for two to four successive evenings [30]. A striking feature of

spasmodic croup is its recurrent nature, hence the alternate

descriptive term, "frequently recurrent croup". There may be a

familial predisposition to spasmodic croup, and it may be more

common in children with a family history of allergies [24].

Early in the clinical course, spasmodic croup may be difficult to

distinguish from laryngotracheitis. As the course progresses,

the episodic nature of spasmodic croup and relative wellness of

the child between attacks differentiate it from classic croup, in

which the symptoms are continuous.

Although the initial presentation can be dramatic, the clinical

course is usually benign. Symptoms are almost always relieved

by comforting the anxious child and administering humidified

air. Rarely, children may benefit from treatment with

corticosteroids and/or nebulized epinephrine [31]. Other

therapies generally are not indicated. (See "Croup: Approach to

management".)

Bacterial tracheitis — Bacterial tracheitis may present as a

primary or secondary infection [32]. In primary infection, there is

acute onset of symptoms of upper airway obstruction with fever

and toxic appearance. In secondary infection, there is marked

worsening during the clinical course of viral laryngotracheitis,

with high fever, toxic appearance, and increasing respiratory

distress secondary to tracheal obstruction from purulent

secretions. In both of these presentations, signs of lower airway

disease, such as crackles and wheezes, may be present.

However, the upper airway obstruction is the more clinically

significant manifestation [2,33]. (See "Bacterial tracheitis in

children: Clinical features and diagnosis", section on 'Clinical

features'.)

Recurrent croup — A child who has had recurrent episodes of

classic viral croup may have an underlying condition that

predisposes him or her to develop clinically significant

narrowing of the upper airway. Recurrent episodes of croup-like

symptoms occurring outside the typical age range for "viral

croup" (ie, six months to three years) and recurrent episodes

that do not appear to be simple "spasmodic croup" should raise

suspicion for large airway lesions, gastroesophageal reflux or

eosinophilic esophagitis, or atopic conditions [3,34-38].

Children with recurrent croup may require radiographic

evaluation or bronchoscopy. (See 'Host factors' above

and 'Imaging' below.)

EVALUATION

Overview — The evaluation of children with suspected croup has

several objectives, including prompt identification of patients

with significant upper airway obstruction or at risk for rapid

progression of upper airway obstruction. In addition, there are

some conditions with presentations similar to that of croup that

require specific evaluationsand/or interventions; these too must

be promptly identified. (See 'Differential diagnosis' below.)

During the evaluation, efforts should be made to make the child

as comfortable as possible. The increased inspiratory effort that

accompanies anxiety and fear in young children can exacerbate

subglottic narrowing, further diminishing air exchange and

oxygenation. (See 'Pathogenesis' above.)

Rapid assessment and initial management — Rapid assessment

of general appearance (including the presence of stridor at

rest), vital signs, pulse oximetry, airway stability, and mental

status is necessary to identify children with severe respiratory

distress and/or impending respiratory failure. (See "Croup:

Approach to management", section on 'Respiratory care'.)

Endotracheal intubation is required in less than 1 percent of

children with croup who are seen in the emergency department.

However, the need for endotracheal intubation should be

anticipated in children with progressive respiratory failure so

that it can be performed in as controlled a setting as possible.

Respiratory failure is heralded by the following signs [1,39,40]:

●Fatigue and listlessness

●Marked retractions (although retractions may decrease

with increased obstruction and decreased air entry)

●Decreased or absent breath sounds

●Depressed level of consciousness

●Tachycardia out of proportion to fever

●Cyanosis or pallor

A tracheal tube that is 0.5 to 1 mm smaller than would typically

be used may be required. (See "Emergency endotracheal

intubation in children", section on 'Endotracheal tube'.)

In addition to establishment of an airway, children who have

severe respiratory distress require immediate pharmacologic

treatment, including administration of nebulizedepinephrine and

systemic or nebulized corticosteroids. (See "Croup: Approach to

management", section on 'Moderate to severe croup'.)

Once control of the airway is established and pharmacologic

treatment, if necessary, is under way, the remainder of the

evaluation can proceed.

History — The history should include a description of the onset,

duration, and progression of symptoms. Factors that are

associated with increased severity of illness include:

●Sudden onset of symptoms

●Rapidly progressing symptoms (ie, symptoms of upper

airway obstruction after fewer than 12 hours of illness)

●Previous episodes of croup

●Underlying abnormality of the upper airway

●Medical conditions that predispose to respiratory failure

(eg, neuromuscular disorders)

Aspects of the history that are helpful in distinguishing croup

from other causes of acute upper airway obstruction include

[1,41]:

●Fever – The absence of fever from onset of symptoms to

the time of presentation is suggestive of spasmodic croup

or a noninfectious etiology (eg, foreign body aspiration or

ingestion, acute angioneurotic edema).

●Hoarseness and barking cough – Hoarseness and

barking cough, characteristic findings in croup, are

typically absent in children with acute epiglottitis, foreign

body aspiration, and angioneurotic edema.

●Difficulty swallowing – Difficulty swallowing may occur in

acute epiglottitis and foreign body aspiration. A large

ingested foreign body may lodge in the upper esophagus,

where it distorts and narrows the upper trachea, thus

mimicking the croup syndrome (including barking cough

and inspiratory stridor).

●Drooling – Drooling may occur in children with

peritonsillar or retropharyngeal abscesses,

retropharyngeal cellulitis, and epiglottitis. In an

observational study, drooling was present in

approximately 80 percent of children with epiglottitis, but

only 10 percent of those with croup [41].

●Throat pain – Complaints of dysphagia and sore throat

are more common in children with epiglottitis than croup

(approximately 60 to 70 percent versus <10 percent) [41].

The differential diagnosis of croup is discussed in greater detail

below. (See 'Differential diagnosis' below.)

Examination — The objectives of the examination of the child

with croup include assessment of severity of upper airway

obstruction and exclusion of other infectious and non-infectious

causes of acute upper airway obstruction, both of which are

necessary in making management decisions.

The initial examination often can be accomplished by observing

the child in a comfortable position with the caretaker. Every

effort should be made to measure the child's weight and vital

signs.

Aspects of the examination that are helpful in assessing the

degree of upper airway obstruction and severity of illness

include:

●Overall appearance – Is the child comfortable and

interactive, anxious and quiet, or obtunded? Is there

stridor at rest? Stridor at rest is a sign of significant upper

airway obstruction. Children with significant upper airway

obstruction may prefer to sit up and lean forward in a

"sniffing" position (neck is mildly flexed, and head is mildly

extended). This position tends to improve the patency of

the upper airway.

●Quality of the voice – Does the child have a hoarse or

diminished cry? Is the voice muffled? A muffled "hot

potato" voice is suggestive of epiglottitis, retropharyngeal

abscess, or peritonsillar abscess.

●Degree of respiratory distress – Signs of respiratory

distress include tachypnea, hypoxemia, and increased

work of breathing (intercostal, subcostal, or suprasternal

retractions; nasal flaring; grunting; use of accessory

muscles)

●Tidal volume – Does there appear to be good chest

expansion with inspiration, indicating adequate air entry?

●Lung examination – Are there abnormal respiratory

sounds during inspiration or expiration? Inspiratory stridor

indicates upper airway obstruction, whereas expiratory

wheezing is a sign of lower airway obstruction. If there is

stridor, is it present at rest or only with agitation? As

discussed above, stridor at rest is a sign of significant

upper airway obstruction. Stridor will be more obvious on

auscultation, since the inspiratory noise is transmitted

through the chest. The presence of crackles (rales) also

suggests lower respiratory tract involvement (eg,

laryngotracheobronchitis,

laryngotracheobronchopneumonitis, or bacterial

tracheitis).

●Assessment of hydration status – Decreased oral intake

and increased insensible losses from fever and

tachypnea may result in dehydration. (See "Clinical

assessment and diagnosis of hypovolemia (dehydration)

in children".)

These aspects of the examination are often used in clinical

scoring systems to evaluate the severity of illness and/or in

making decisions regarding the need for hospital admission.

(See 'Severity assessment' below and "Croup: Approach to

management", section on 'Observation and disposition'.)

Components of the examination that are useful in distinguishing

croup from other causes of acute upper airway obstruction

include [39,41]:

●Preferred posture – Children with epiglottitis usually

prefer to sit up in the "tripod" or "sniffing position" (picture

2A-B).

●Examination of the oropharynx for the following signs:

•Cherry red, swollen epiglottis, suggestive of

epiglottitis

•Pharyngitis, typically minimal in laryngotracheitis,

may be more pronounced in epiglottitis or laryngitis

•Excessive salivation, suggestive of acute

epiglottitis, peritonsillar abscess, or retropharyngeal

abscess

•Diphtheritic membrane

•Tonsillar asymmetry or deviation of the uvula

suggestive of peritonsillar abscess

•Midline or unilateral swelling of the posterior

pharyngeal wall suggestive of retropharyngeal

abscess

Concerns have been raised about safety of

examining the pharynx in children with upper airway

obstruction and possible epiglottitis since such

efforts have been reported to precipitate

cardiorespiratory arrest. However, in two series,

each including more than 200 patients with

epiglottitis or viral croup, direct examination of the

oropharynx was not associated with sudden clinical

deterioration [32,42].

●Examination of the cervical lymph nodes, which can be

enlarged in patients with retropharyngeal or peritonsillar

abscesses.

●Other physical findings may be present, depending on

the particular inciting virus. As an example, rash,

conjunctivitis, exudative pharyngitis, and adenopathy are

suggestive of adenovirus infection.

●Otitis media (acute or with effusion) may be present as a

primary viral or secondary bacterial process.

The differential diagnosis of croup is discussed in greater detail

below. (See 'Differential diagnosis' below.)

Severity assessment — The severity of croup is often

determined by the clinical scoring systems. Although there are a

number of validated croup scoring systems, the Westley croup

score [43] has been the most extensively studied; it is described

below. No matter which system is used to assess severity, the

presence of chest wall retractions and stridor at rest are the two

critical clinical features.

The elements of the Westley croup score describe key features

of the physical examination [43]. Each element is assigned a

score, as illustrated below:

●Level of consciousness: Normal, including sleep = 0;

disoriented = 5

●Cyanosis: None = 0; with agitation = 4; at rest = 5

●Stridor: None = 0; with agitation = 1; at rest = 2

●Air entry: Normal = 0; decreased = 1; markedly

decreased = 2

●Retractions: None = 0; mild = 1; moderate = 2; severe =

3

Mild croup is defined by a Westley croup score of ≤2. Typically,

these children have a barking cough and hoarse cry, but no

stridor at rest. Children with mild croup may have stridor when

upset or crying (ie, agitated) and either no, or only mild,

chest wall/subcostal retractions [1,39].

Moderate croup is defined by a Westley croup score of 3 to 7.

Children with moderate croup have stridor at rest, at least mild

retractions, and may have other symptoms or signs of

respiratory distress, but little or no agitation [1,39].

Severe croup is defined by a Westley croup score of ≥8.

Children with severe croup have significant stridor at rest,

although stridor may decrease with worsening upper airway

obstruction and decreased air entry [1,39]. Retractions are

severe (including indrawing of the sternum) and the child may

appear anxious, agitated, or fatigued. Prompt recognition and

treatment of children with severe croup are paramount.

Imaging

Indications — Radiographic confirmation of acute

laryngotracheitis is not required in the vast majority of children

with croup. Radiographic evaluation of the chestand/or upper

trachea is indicated if the diagnosis is in question, the course is

atypical, an inhaled or swallowed foreign body is suspected

(although the majority are not radio-opaque), croup is

recurrent, and/or there is a failure to respond as expected to

therapeutic interventions. (See 'Differential diagnosis' below

and "Croup: Approach to management".)

Findings — In children with croup, a posterior-anterior chest

radiograph demonstrates subglottic narrowing, commonly called

the "steeple sign" (image 1). The lateral view may demonstrate

overdistention of the hypopharynx during inspiration [44] and

subglottic haziness (image 2). The epiglottis should have a

normal appearance.

In contrast, the lateral radiograph in virtually all children with

epiglottitis demonstrates swelling of the epiglottis, sometimes

called the "thumb sign" (image 3). (See"Epiglottitis

(supraglottitis): Clinical features and diagnosis", section on

'Radiographic features'.)

The lateral radiograph in children with bacterial tracheitis may

demonstrate only nonspecific edema or intraluminal

membranes and irregularities of the tracheal wall (image 4) [45].

Laboratory studies — Laboratory studies, which are rarely

indicated in children with croup, are of limited diagnostic utility

but may help guide management in more severe cases.

Blood tests — The white blood cell (WBC) count can be low,

normal, or elevated; WBC counts >10,000 cells/microL are

common. Neutrophil or lymphocyte predominance may be

present on the differential [46,47]. The presence of a large

number of band-form neutrophils is suggestive of primary or

secondary bacterial infection. Croup is not associated with any

specific alterations in serum chemistries.

Microbiology — Confirmation of etiologic diagnosis is not

necessary for most children with croup, since croup is a self-

limited illness that usually requires only symptomatic therapy.

When an etiologic diagnosis is necessary, viral

culture and/or rapid diagnostic tests that detect viral antigens

are performed on secretions from the nasopharynx or throat.

(See 'Etiologic diagnosis' below.)

DIAGNOSIS

Clinical diagnosis — The diagnosis of croup is clinical, based on

the presence of a barking cough and stridor, especially during a

typical community epidemic of one of the causative viruses.

(See 'Etiology' above.)

Neither radiographs nor laboratory tests are necessary to make

the diagnosis. However, radiographs may be helpful in

excluding other causes if the diagnosis is in question.

(See 'Differential diagnosis' below.)

Etiologic diagnosis — Although not typically required in most

cases of croup, identification of a specific viral etiology may be

necessary to make decisions regarding isolation for patients

requiring hospitalization or for

public health/epidemiologic monitoring purposes. Testing for

influenza is indicated if the results will influence decisions

regarding treatment, prophylaxis of contacts, or performance of

other diagnostic tests; laboratory confirmation should not delay

the initiation of antiviral therapy for influenza when clinical and

seasonal considerations are compatible with influenza as the

potential etiology of croup. (See "Seasonal influenza in children:

Clinical features and diagnosis", section on 'Laboratory

diagnosis' and "Seasonal influenza in children: Prevention and

treatment with antiviral drugs", section on 'Timing of treatment'.)

Diagnosis of a specific viral etiology can be made by viral

culture of secretions from the nasopharynx or throat. Rapid

tests that detect viral antigens in these secretions are

commercially available for many respiratory viruses. The

diagnosis of specific viral infections is discussed in detail in

individual topic reviews:

●Parainfluenza (see "Parainfluenza viruses in children",

section on 'Diagnosis')

●Influenza (see "Seasonal influenza in children: Clinical

features and diagnosis", section on 'Diagnosis')

●Respiratory syncytial virus (see "Respiratory syncytial

virus infection: Clinical features and diagnosis", section on

'Laboratory diagnosis')

●Adenovirus (see "Diagnosis, treatment, and prevention

of adenovirus infection", section on 'Diagnostic tests of

choice for different adenovirus syndromes')

●Measles (see "Clinical manifestations and diagnosis of

measles", section on 'Diagnosis')

●Enteroviruses (see "Clinical manifestations and

diagnosis of enterovirus and parechovirus infections",

section on 'Laboratory diagnosis')

●Metapneumovirus (see "Human metapneumovirus

infections", section on 'Diagnosis')

●Coronavirus (see "Coronaviruses", section on

'Diagnosis')

In addition, multiplex tests, which assess the presence of

multiple agents at the same time, and PCR-based tests are

becoming more widely available [48].

DIFFERENTIAL DIAGNOSIS — The differential diagnosis of

croup includes other causes of stridor and/or respiratory

distress. The primary considerations are those with acute onset,

particularly those that may rapidly progress to complete upper

airway obstruction, and those that require specific therapy.

Underlying anatomic anomalies of the upper airway also must

be considered, since they may contribute to more severe

disease. (See 'Host factors' above.)

Important considerations include [1,12]:

●Acute epiglottitis

●Peritonsillar and retropharyngeal abscesses

●Foreign body aspiration or ingestion

●Allergic reaction

●Acute angioneurotic edema

●Upper airway injury

●Congenital anomalies of the upper airway

●Laryngeal diphtheria (see "Clinical manifestations,

diagnosis and treatment of diphtheria")

Acute epiglottitis – Epiglottitis, which is rare in the era of

vaccination against Haemophilus influenzae type b, is

distinguished from croup by the absence of barking cough and

the presence of anxiety that is out of proportion to the degree of

respiratory distress. Onset of symptoms is rapid, and because

of the associated bacteremia, the child is highly febrile, pale,

toxic, and ill-appearing. Because of the swollen epiglottis, the

child will have difficulty swallowing and is often drooling. The

children usually prefer to sit up and seldom have observed

cough [41]. Epiglottitis occurs infrequently, and there is no

predominant etiologic pathogen. (See "Epiglottitis

(supraglottitis): Clinical features and diagnosis".)

Peritonsillar or retropharyngeal abscesses – Children with deep

neck space abscesses, cellulitis of the cervical prevertebral

tissues, or other painful infections of the oropharynx may

present with drooling and neck extension and varying degrees

of toxicity. Barking cough is usually absent. (See "Peritonsillar

cellulitis and abscess", section on

'Presentation' and "Retropharyngeal infections in children",

section on 'Presentation'.)

Foreign body – In foreign body aspiration, there often is a history

of the sudden onset of choking and symptoms of upper airway

obstruction in a previously healthy child. If an inhaled foreign

body lodges in the larynx, it will produce hoarseness and stridor.

If a large foreign body is swallowed, it may lodge in the upper

esophagus, resulting in distortion of the adjacent soft

extrathoracic trachea, producing a barking cough and

inspiratory stridor. (See "Airway foreign bodies in

children" and "Foreign bodies of the esophagus and

gastrointestinal tract in children".)

Allergic reaction or acute angioneurotic edema – Allergic

reaction or acute angioneurotic edema has rapid onset without

antecedent cold symptoms or fever. The primary manifestations

are swelling of the lips and tongue, urticarial rash, dysphagia

without hoarseness, and sometimes inspiratory stridor [1,12].

There may be a history of allergy or a previous attack. (See "An

overview of angioedema: Clinical features, diagnosis, and

management", section on 'Clinical features'.)

Upper airway injury – Injury to the airway from smoke or thermal

or chemical burns should be evident from the history. The child

typically does not have fever or a viral prodrome.

Anomalies of the upper airway – Hoarseness and stridor caused

by anomalies of the upper airway (eg, laryngeal webs,

laryngomalacia, vocal cord paralysis, congenital subglottic

stenosis, and subglottic hemangioma) and laryngeal papillomas

have a more chronic course with absence of fever and

symptoms of upper respiratory tract illness, unless the

presentation is due to exacerbation of airway narrowing from

the impact of a concomitant viral infection. (See "Assessment of

stridor in children" and"Hoarseness in children: Etiology and

management" and "Congenital anomalies of the larynx".)

Other potential mimickers of croup – Other potential mimickers

of croup include bronchogenic cyst (which can cause airway

compression) and early Guillain-Barré syndrome (involvement

of the laryngeal nerve may cause vocal cord paralysis) [49,50].

(See "Congenital anomalies of the intrathoracic airways and

tracheoesophageal fistula", section on 'Bronchogenic

cyst' and "Epidemiology, clinical features, and diagnosis of

Guillain-Barré syndrome in children", section on 'Clinical

features' and"Hoarseness in children: Etiology and

management", section on 'Vocal fold paralysis'.)

INFORMATION FOR PATIENTS — UpToDate offers two types

of patient education materials, "The Basics" and "Beyond the

Basics." The Basics patient education pieces are written in plain

language, at the 5th

to 6th

grade reading level, and they answer

the four or five key questions a patient might have about a given

condition. These articles are best for patients who want a

general overview and who prefer short, easy-to-read materials.

Beyond the Basics patient education pieces are longer, more

sophisticated, and more detailed. These articles are written at

the 10th

to 12th

grade reading level and are best for patients who

want in-depth information and are comfortable with some

medical jargon.

Here are the patient education articles that are relevant to this

topic. We encourage you to print or e-mail these topics to your

patients. (You can also locate patient education articles on a

variety of subjects by searching on "patient info" and the

keyword(s) of interest.)

●Basics topic (see "Patient information: Croup (The

Basics)")

●Beyond the Basics topic (see "Patient information:

Croup in infants and children (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●The term croup has been used to describe a variety of

upper respiratory conditions in children, including

laryngitis, laryngotracheitis, laryngotracheobronchitis,

bacterial tracheitis, or spasmodic croup.

(See 'Definitions' above.)

●Croup is usually caused by viruses. Bacterial infection

may occur secondarily. Parainfluenza virus type 1 is the

most common cause of croup; other causes include

respiratory syncytial virus and influenza virus.

(See 'Etiology' above.)

●Croup most commonly occurs in children 6 to 36 months

of age. Most cases occur in the fall or early winter.

(See 'Epidemiology' above.)

●Host factors that may contribute to the development of

croup include functional or anatomic susceptibility to

upper airway narrowing. (See 'Pathogenesis' above.)

●The clinical presentation of croup depends upon the

specific croup syndrome and the degree of upper airway

obstruction. (See 'Clinical presentation' above.)

●The onset of symptoms in laryngotracheitis is gradual,

beginning with nasal irritation, congestion, and coryza.

Fever, hoarseness, barking cough, and stridor usually

develop during the next 12 to 48 hours. Rapid progression

or signs of lower airway involvement suggest a more

serious illness. (See 'Laryngotracheitis' above.)

●The onset of symptoms in spasmodic croup is sudden

and always occurs at night. Fever is typically absent, but

mild upper respiratory tract symptoms may be present.

(See 'Spasmodic croup' above.)

●Bacterial tracheitis (picture 1 and image 4) may present

acutely or as marked worsening during the course of an

antecedent viral upper respiratory infection. Clinical

manifestations of bacterial tracheitis include fever, toxic

appearance, and severe respiratory distress.

(See 'Bacterial tracheitis' above and "Bacterial tracheitis

in children: Clinical features and diagnosis".)

●The objectives of the evaluation of the child with croup

include assessment of severity and exclusion of other

causes of upper airway obstruction.

(See 'Overview'above.)

●Rapid assessment of general appearance, vital signs,

pulse oximetry, airway stability, and mental status are

necessary to identify children with severe respiratory

distress and/or impending respiratory failure. (See 'Rapid

assessment and initial management' above.)

●The history should include a description of the onset,

duration and progression of symptoms, and ascertain

whether there are any underlying conditions that

predispose to a more severe course.

(See 'History' above.)

●Aspects of the examination that are useful in assessing

the severity of upper airway obstruction include overall

appearance (including the presence of stridor at rest or

only with agitation), quality of voice, work of breathing,

tidal volume and air entry, and the presence of wheezing.

(See 'Examination' above.)

●The diagnosis of croup is clinical, based upon the

presence of a barking cough and stridor. Neither

radiographs nor laboratory tests are necessary to make

the diagnosis. However, radiographs may be helpful in

excluding other causes if the diagnosis is in question.

(See 'Diagnosis' above.)

●The differential diagnosis of croup includes other causes

of stridor and/or respiratory distress. The primary

considerations are those with acute onset, particularly

those that may rapidly progress to complete upper airway

obstruction, and those that require specific therapy.

Important considerations include acute epiglottitis,

peritonsillar and retropharyngeal abscesses, foreign body

aspiration, acute angioneurotic edema, upper airway

injury, and congenital anomalies of the upper airway.

(See 'Differential diagnosis' above.)

Use of UpToDate is subject to the Subscription and License Agreement.

REFERENCES

1. Cherry JD. Clinical practice. Croup. N Engl J Med 2008; 358:384.

2. Cherry JD. Croup (laryngitis, laryngotracheitis, spasmodic croup, laryngotracheobronchitis, bacterial tracheitis, and laryngotracheobronchopneumonitis) and epiglottitis (supraglottitis). In: Feigin and Cherry’s Textbook of Pediatric Infectious Diseases, 7th ed, Cherry JD, Harrison GJ, Kaplan SL, et al (Eds), Elsevier Saunders, Philadelphia 2014. p.241.

3. Cooper T, Kuruvilla G, Persad R, El-Hakim H. Atypical croup: association with airway lesions, atopy, and esophagitis. Otolaryngol Head Neck Surg 2012; 147:209.

4. Peltola V, Heikkinen T, Ruuskanen O. Clinical courses of croup caused by influenza and parainfluenza viruses. Pediatr Infect Dis J 2002; 21:76.

5. Counihan ME, Shay DK, Holman RC, et al. Human parainfluenza virus-associated hospitalizations among children less than five years of age in the United States. Pediatr Infect Dis J 2001; 20:646.

6. Rihkanen H, Rönkkö E, Nieminen T, et al. Respiratory viruses in laryngeal croup of young children. J Pediatr 2008; 152:661.

7. Weinberg GA, Hall CB, Iwane MK, et al. Parainfluenza virus infection of young children: estimates of the population-based burden of hospitalization. J Pediatr 2009; 154:694.

8. Kuypers J, Martin ET, Heugel J, et al. Clinical disease in children associated with newly described coronavirus subtypes. Pediatrics 2007; 119:e70.

9. Sung JY, Lee HJ, Eun BW, et al. Role of human coronavirus NL63 in hospitalized children with croup. Pediatr Infect Dis J 2010; 29:822.

10. van der Hoek L, Sure K, Ihorst G, et al. Croup is associated with the novel coronavirus NL63. PLoS Med 2005; 2:e240.

11. Døllner H, Risnes K, Radtke A, Nordbø SA. Outbreak of human metapneumovirus infection in norwegian children. Pediatr Infect Dis J 2004; 23:436.

12. Bjornson CL, Johnson DW. Croup. Lancet 2008; 371:329. 13. Segal AO, Crighton EJ, Moineddin R, et al. Croup

hospitalizations in Ontario: a 14-year time-series analysis. Pediatrics 2005; 116:51.

14. Rosychuk RJ, Klassen TP, Metes D, et al. Croup presentations to emergency departments in Alberta, Canada: a large population-based study. Pediatr Pulmonol 2010; 45:83.

15. Pruikkonen H, Dunder T, Renko M, et al. Risk factors for croup in children with recurrent respiratory infections: a case-control study. Paediatr Perinat Epidemiol 2009; 23:153.

16. Salzman MB, Filler HF, Schechter CB. Passive smoking and croup. Arch Otolaryngol Head Neck Surg 1987; 113:866.

17. Marx A, Török TJ, Holman RC, et al. Pediatric hospitalizations for croup (laryngotracheobronchitis): biennial increases associated with human parainfluenza virus 1 epidemics. J Infect Dis 1997; 176:1423.

18. DAVISON FW. Acute laryngeal obstruction in children. J Am Med Assoc 1959; 171:1301.

19. Davison FW. Acute obstructive laryngitis in children. Penn Med J 1950; 53:250.

20. Szpunar J, Glowacki J, Laskowski A, Miszke A. Fibrinous laryngotracheobronchitis in children. Arch Otolaryngol 1971; 93:173.

21. MORGAN EA, WISHART DE. Laryngotracheo-bronchitis (a statistical review of 549 cases). Can Med Assoc J 1947; 56:8.

22. Orton HB, Smith EL, Bell HO, et al. Acute laryngotracheobronchitis: analysis of sixty-two cases with report of autopsies in eight cases. Arch Otolaryngol 1941; 33:926.

23. Richards L. A further study of the pathology of acute laryngo-tracheobronchitis in children. Ann Otol Rhinol Laryngol 1938; 47:326.

24. Hide DW, Guyer BM. Recurrent croup. Arch Dis Child 1985; 60:585.

25. Van Bever HP, Wieringa MH, Weyler JJ, et al. Croup and recurrent croup: their association with asthma and allergy. An epidemiological study on 5-8-year-old children. Eur J Pediatr 1999; 158:253.

26. Gilger MA. Pediatric otolaryngologic manifestations of gastroesophageal reflux disease. Curr Gastroenterol Rep 2003; 5:247.

27. Welliver RC, Sun M, Rinaldo D. Defective regulation of immune responses in croup due to parainfluenza virus. Pediatr Res 1985; 19:716.

28. Welliver RC, Wong DT, Middleton E Jr, et al. Role of parainfluenza virus-specific IgE in pathogenesis of croup and wheezing subsequent to infection. J Pediatr 1982; 101:889.

29. Thompson M, Vodicka TA, Blair PS, et al. Duration of symptoms of respiratory tract infections in children: systematic review. BMJ 2013; 347:f7027.

30. Cherry JD. The treatment of croup: continued controversy due to failure of recognition of historic, ecologic, etiologic and clinical perspectives. J Pediatr 1979; 94:352.

31. Kaditis AG, Wald ER. Viral croup: current diagnosis and treatment. Pediatr Infect Dis J 1998; 17:827.

32. Mauro RD, Poole SR, Lockhart CH. Differentiation of epiglottitis from laryngotracheitis in the child with stridor. Am J Dis Child 1988; 142:679.

33. Kasian GF, Bingham WT, Steinberg J, et al. Bacterial tracheitis in children. CMAJ 1989; 140:46.

34. Duval M, Tarasidis G, Grimmer JF, et al. Role of operative airway evaluation in children with recurrent croup: a retrospective cohort study. Clin Otolaryngol 2015; 40:227.

35. Delany DR, Johnston DR. Role of direct laryngoscopy and bronchoscopy in recurrent croup. Otolaryngol Head Neck Surg 2015; 152:159.

36. Rankin I, Wang SM, Waters A, et al. The management of recurrent croup in children. J Laryngol Otol 2013; 127:494.

37. Jabbour N, Parker NP, Finkelstein M, et al. Incidence of operative endoscopy findings in recurrent croup. Otolaryngol Head Neck Surg 2011; 144:596.

38. Chun R, Preciado DA, Zalzal GH, Shah RK. Utility of bronchoscopy for recurrent croup. Ann Otol Rhinol Laryngol 2009; 118:495.

39. Alberta Clinical Practice Guidelines Guideline Working Group. Guidelines for the diagnosis and management of croup http://www.topalbertadoctors.org.sci-hub.org/informed_practice/cpgs/croup.html (Accessed on February 22, 2011).

40. Fleisher G. Infectious disease emergencies. In: Textbook of Pediatric Emergency Medicine, 5th ed, Fleisher GR, Ludwig S, Henretig FM (Eds), Lippincott, Williams & Wilkins, Philadelphia 2006. p.783.

41. Tibballs J, Watson T. Symptoms and signs differentiating croup and epiglottitis. J Paediatr Child Health 2011; 47:77.

42. Diaz JH, Lockhart CH. Early diagnosis and airway management of acute epiglottitis in children. South Med J 1982; 75:399.

43. Westley CR, Cotton EK, Brooks JG. Nebulized racemic epinephrine by IPPB for the treatment of croup: a double-blind study. Am J Dis Child 1978; 132:484.

44. Mills JL, Spackman TJ, Borns P, et al. The usefulness of lateral neck roentgenograms in laryngotracheobronchitis. Am J Dis Child 1979; 133:1140.

45. Bernstein T, Brilli R, Jacobs B. Is bacterial tracheitis changing? A 14-month experience in a pediatric intensive care unit. Clin Infect Dis 1998; 27:458.

46. Cherry JD. Newer respiratory viruses: their role in respiratory illnesses of children. In: Advances in Pediatrics, Vol 20, Schulman I (Ed), Mosby Year Book, Chicago 1973. p.225.

47. Denny FW, Clyde WA Jr. Acute lower respiratory tract infections in nonhospitalized children. J Pediatr 1986; 108:635.

48. Henrickson KJ, Hoover S, Kehl KS, Hua W. National disease burden of respiratory viruses detected in children by polymerase chain reaction. Pediatr Infect Dis J 2004; 23:S11.

49. Lin CY, Chi H, Shih SL, et al. A 4-year-old boy presenting with recurrent croup. Eur J Pediatr 2010; 169:249.

50. Hsia SH, Lin JJ, Wu CT, et al. Guillain-Barré syndrome presenting as mimicking croup. Am J Emerg Med 2010; 28:749.e1.

Topic 6002 Version 20.0

Croup: Approach to management Author Charles R Woods, MD, MS Section Editors Sheldon L Kaplan, MD Anna H Messner, MD Deputy Editor Carrie Armsby, MD, MPH Disclosures: Charles R Woods, MD, MS Other Financial Interest: Cerexa [Epiglottitis (Data Safety Monitoring Board for pediatric trials of the antibiotic agent ceftaroline)]. Sheldon L Kaplan, MDGrant/Research/Clinical Trial Support: Pfizer [vaccine (PCV13)]; Forest Lab [antibiotic (Ceftaroline)]; Optimer [antibiotic (fidaxomicin)]. Consultant/Advisory Boards: Pfizer [vaccine (PCV13)]. Anna H Messner, MD Nothing to disclose. Carrie Armsby, MD, MPH Nothing to disclose.

Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence.

Conflict of interest policy

All topics are updated as new evidence becomes available and our peer review process is complete. Literature review current through: Jul 2015. | This topic last updated: Apr 17, 2015.

INTRODUCTION — Croup (laryngotracheitis) is a

respiratory illness characterized by inspiratory stridor,

barking cough, and hoarseness. It typically occurs in

children six months to three years of age and is chiefly

caused by parainfluenza virus. (See "Croup: Clinical

features, evaluation, and diagnosis".)

Most children with croup who seek medical attention

have a mild, self-limited illness and can be successfully

managed as outpatients. The clinician must be able to

identify children with mild symptoms, who can be safely

managed at home, and those with moderate to severe

croup or rapidly progressing symptoms, who require full

evaluation and possible treatment in the office or

emergency department setting. (See 'Severity

assessment' below and 'Outpatient treatment' below.)

There is no definitive treatment for the viruses that cause

croup. Pharmacologic therapy is directed toward

decreasing airway edema, and supportive care is

directed toward the provision of respiratory support and

the maintenance of hydration. Corticosteroids and

nebulized epinephrine are the cornerstones of therapy;

their use is supported by substantial clinical evidence.

(See 'Initial treatment' below and "Croup: Pharmacologic

and supportive interventions".)

The approach to the management of croup will be

discussed below. The clinical features and evaluation of

croup, and the evidence supporting the use of the

pharmacologic and supportive interventions included

below are discussed separately. (See "Croup: Clinical

features, evaluation, and diagnosis" and "Croup:

Pharmacologic and supportive interventions".)

SEVERITY ASSESSMENT — This initial step in the

management of a child with croup is assessing severity

of illness. The first contact with the healthcare system

may occur by phone and the healthcare provider must be

able to distinguish children with more severe symptoms

who need immediate medical attention from those who

can be managed at home. (See 'Telephone

triage' below.)

When the child is seen in the office or emergency

department, croup severity is assessed by examining the

child and using a clinical scoring system. (See 'Croup

severity score' below.)

Telephone triage — When assessing patients by phone,

the healthcare provider must distinguish children who

need immediate medical attention or further evaluation

from those who can be managed at home. Children who

need further evaluation include those who have:

●Stridor at rest

●Rapid progression of symptoms (ie, symptoms of

upper airway obstruction after less than 12 hours of

illness)

●Inability to tolerate oral fluids

●Underlying known airway abnormality (eg,

subglottic stenosis, subglottic hemangioma,

previous intubation)

●Previous episodes of moderate to severe croup

●Medical conditions that predispose to respiratory

failure (eg, neuromuscular disorders or

bronchopulmonary dysplasia)

●Parental concern that cannot be relieved by

reassurance

●Prolonged symptoms (more than three to seven

days) or an atypical course (perhaps indicating an

alternative diagnosis) (see "Croup: Clinical features,

evaluation, and diagnosis", section on 'Differential

diagnosis')

Patients who are assessed by phone and determined to

have mild symptoms and none of the above indications

for further evaluation can be managed at home.

(See'Home treatment' below.)

Croup severity score — There are a number of

validated croup scoring systems. The Westley croup

score has been the most extensively studied (table 1) [1].

Severity is determined by the presence or absence of

stridor at rest, the degree of chest wall retractions, air

entry, the presence or absence of pallor or cyanosis, and

the mental status:

●Mild croup (Westley croup score of ≤2) − Children

with mild croup have no stridor at rest (although

stridor may be present when upset or crying), a

barking cough, hoarse cry, and either no, or only

mild, chest wall/subcostal retractions [2-4].

(See 'Mild croup' below.)

●Moderate croup (Westley croup score of 3 to 7) −

Children with moderate croup have stridor at rest,

have at least mild retractions, and may have other

symptoms or signs of respiratory distress, but little

or no agitation [2-4]. (See 'Moderate to severe

croup' below.)

●Severe croup (Westley croup score of ≥8) −

Children with severe croup have significant stridor

at rest, although the loudness of the stridor may

decrease with worsening upper airway obstruction

and decreased air entry [2-4]. Retractions are

severe (including indrawing of the sternum) and the

child may appear anxious, agitated, or pale and

fatigued. Prompt recognition and treatment of

children with severe croup are paramount.

(See 'Moderate to severe croup' below.)

●Impending respiratory failure (Westley croup

score of ≥12) − Croup occasionally results in

significant upper airway obstruction with impending

respiratory failure, heralded by the following signs

[2,4,5]:

•Fatigue and listlessness

•Marked retractions (although retractions may

decrease with increased obstruction and

decreased air entry)

•Decreased or absent breath sounds

•Depressed level of consciousness

•Tachycardia out of proportion to fever

•Cyanosis or pallor

Patients who present to an office clinic with severe

croup or signs and symptoms of impending

respiratory failure should be transported via

emergency medical services to an emergency

department for management. (See 'Moderate to

severe croup' below.)

MILD CROUP — Children with mild symptoms (Westley

croup score of ≤2 (table 1)) should be treated

symptomatically with humidity, fever reduction, and oral

fluids. Many such children can be managed by phone,

provided that none of the criteria for further evaluation

described above are present. (See 'Telephone

triage' above.)

Home treatment — The caregivers of children with mild

croup who are managed at home should be instructed in

provision of supportive care including mist, antipyretics,

and encouragement of fluid intake.

In acute situations and for short periods of time,

caregivers may try sitting with the child in a bathroom

filled with steam generated by running hot water from the

shower to improve symptoms. This may help reassure

parents that "something" is being done to reverse the

symptoms, and anecdotal evidence supports some

benefit with this measure.

Exposure to cold night air also may lessen symptoms of

mild croup, although this has never been systematically

studied. If parents or caregivers wish to use humidifiers

at home, only those that produce mist at room

temperature should be used to avoid the risk of burns

from steam or the heating element.

Instructions should be provided to the caregivers

regarding when to seek medical attention, including

watching for [2]:

●Stridor at rest

●Difficulty breathing

●Pallor or cyanosis

●Severe coughing spells

●Drooling or difficulty swallowing

●Fatigue

●Worsening course

●Fever (>38.5ºC)

●Prolonged symptoms (longer than seven days)

●Suprasternal retractions

Caregivers also should be provided with some guidance

regarding when it is safe for them to drive the child to the

emergency department; emergency medical services

should provide transportation for children who are

severely agitated, pale or cyanotic, struggling to breathe,

or lethargic [2].

Patients who are managed at home should receive a

follow-up phone call within 24 hours.

Outpatient treatment — We suggest that children with

mild croup who are seen in the outpatient setting be

treated with a single dose of

oral dexamethasone (0.6 mg/kg)(algorithm 1).

Randomized controlled trials in children with mild croup

have demonstrated that treatment with a single dose of

oral dexamethasone (0.15 to 0.6 mg/kg,maximum dose

10 mg) reduces the need for reevaluation, shortens the

duration of symptoms, improves the child's sleep, and

reduces parental stress [6,7]. (See "Croup:

Pharmacologic and supportive interventions", section on

'Dexamethasone'.)

An alternative approach is nonpharmacologic

management with anticipatory guidance about potential

worsening and instructions on when to seek care or

return for follow-up.

Treatment with nebulized epinephrine is not typically

necessary for management of mild croup.

Children with mild croup who are tolerating fluids and

have not received nebulized epinephrine can be sent

home after specific follow-up (which may occur by phone)

has been arranged and the caregiver has received

instructions regarding home care and indications to seek

medical attention as described above. (See 'Home

treatment'above.)

MODERATE TO SEVERE CROUP

Setting and pace of treatment — The appropriate

treatment setting depends upon the severity of

symptoms:

●Children with moderate croup (Westley croup

score 3 to 7; stridor at rest and mild to moderate

retractions, but no or little distress or agitation (table

1)) should be evaluated in the emergency

department or office (provided the office is equipped

to handle acute upper airway obstruction).

●Children with severe croup (Westley croup score

≥8; stridor at rest and marked retractions with

agitation, lethargy, or cyanosis (table 1)) should be

evaluated in the emergency department as they

require aggressive therapy, monitoring, and

supportive care.

The child with severe croup must be approached

cautiously, as any increase in anxiety may worsen airway

obstruction. The parent or caregiver should be instructed

to hold and comfort the child.

Nebulized epinephrine should be added as quickly as

possible, as described below. In the meantime,

healthcare providers should continuously observe the

child and be prepared to provide bag-mask ventilation

and advanced airway techniques if the condition worsens

(algorithm 1). (See 'Initial treatment' below

and 'Respiratory care' below.)

Initial treatment — Initial treatment of moderate to

severe croup includes administration

of dexamethasone and nebulized epinephrine. Children

with moderate to severe croup should also receive

supportive care including humidified air or oxygen,

antipyretics, and encouragement of fluid intake.

(See 'Supportive care' below.)

We recommend administration

of dexamethasone (0.6 mg/kg, maximum of 10 mg) in all

children with moderate to severe croup. Dexamethasone

should be administered by the least invasive route

possible: oral if oral intake is tolerated, intravenous (IV) if

IV access has been established, or intramuscular (IM) if

oral intake is not tolerated and IV access has not been

established. The oral preparation of dexamethasone

(1 mg/mL) has an unpleasant taste. The IV preparation is

more concentrated (4 mg per mL) and can be given orally

mixed with syrup [2,8-10]. A single dose of

nebulized budesonide (2 mg [2 mL solution] via

nebulizer) is an alternative option, particularly for children

who are vomiting [2,4,11].

The benefit of corticosteroids for moderate to severe

croup have been demonstrated in a meta-analysis of 24

trials that found improvement in croup scores six hours

after treatment, fewer return visits or readmissions,

decreased length of stay in the emergency department or

hospital, and decreased epinephrine use [12].

(See "Croup: Pharmacologic and supportive

interventions", section on 'Glucocorticoids'.)

In addition to dexamethasone, we recommend

nebulized epinephrine in all patients with moderate to

severe croup:

●Racemic epinephrine is administered as

0.05 mL/kg per dose (maximum of 0.5 mL) of a 2.25

percent solution diluted to 3 mL total volume with

normal saline. It is given via nebulizer over 15

minutes.

●L-epinephrine is administered as 0.5 mL/kg per

dose (maximum of 5 mL) of a 1:1000 dilution. It is

given via nebulizer over 15 minutes.

The benefits of nebulized epinephrine have been

demonstrated in a meta-analysis of eight trials that found

improvement in croup score 30 minutes post-treatment

and shorter hospital stay; there was no difference in

effectiveness between racemic epinephrine and L-

epinephrine [13]. (See "Croup: Pharmacologic and

supportive interventions", section on 'Nebulized

epinephrine'.)

Observation and disposition — Patients should be

observed for three to four hours after initial treatment.

The need for additional intervention and/or admission to

the hospital is determined chiefly by the response to

therapy with corticosteroids and nebulized epinephrine.

The majority of children with moderate croup have

symptomatic improvement after treatment with nebulized

epinephrine and corticosteroids and can be discharged

home, whereas those with severe symptoms on

presentation are more likely to require hospitalization.

Discharge to home — Patients who have a good

response to initial treatment should be observed for three

to four hours after pharmacologic intervention (algorithm

1) [14-17]. Croup symptoms usually improve within 30

minutes of administration of nebulized epinephrine, but

may recur as the effects of epinephrine wear off (usually

by two hours) [18,19]. Children who have recurrence or

worsening of moderate to severe symptoms during the

observation period should receive additional racemic

epinephrine and should be admitted to the hospital.

(See 'Indications for hospital admission' below.)

After three to four hours of observation, children who

remain comfortable may be discharged home if they

meet the following criteria [14-17]:

●No stridor at rest

●Normal pulse oximetry

●Good air exchange

●Normal color

●Normal level of consciousness

●Demonstrated ability to tolerate fluids by mouth

●Caregivers understand the indications for return to

care and would be able to return if necessary

Before discharge, follow-up with the primary care

provider should be arranged within the next 24 hours.

Instructions regarding home treatment should be

provided. (See'Home treatment' above.)

Approximately 5 percent of children well enough for

discharge from the emergency department after receiving

corticosteroids and nebulized epinephrine treatments are

expected to return for care [20]. Relapse within 24 hours

is unlikely in those who have minimal symptoms at the

time of discharge [21].

Indications for hospital admission — Patients with

ongoing severe symptoms after initial treatment should

receive additional nebulized epinephrine and should be

admitted to the hospital. Nebulized epinephrine can be

repeated every 15 to 20 minutes. The administration of

three or more doses within a two- to three-hour time

period should prompt initiation of close cardiac

monitoring if this is not already underway.

Children with persistent moderate symptoms can be

observed for at least four hours before deciding whether

they require hospital admission as the effect

ofdexamethasone may not be apparent for several hours

[2].

Indications for inpatient admission include [2,22]:

●Severe croup with poor air entry, altered

consciousness, or impending respiratory failure

●Moderate/severe croup with persistent or

deteriorating respiratory distress after treatment

with nebulized epinephrine and corticosteroids

●"Toxic" appearance or clinical picture suggesting

serious secondary bacterial infection

●Need for supplemental oxygen

●Severe dehydration

Additional factors that influence the decision regarding

admission include [2,22]:

●Young age, particularly younger than six months

●Recurrent visits to the emergency department

within 24 hours

●Ability of the family to comprehend the instructions

regarding recognition of features that indicate the

need to return for care

●Ability of the family to return for care (eg, distance

from home to care site, weather/travel conditions)

Admission to the pediatric intensive care unit (PICU) is

warranted if any of the following are present:

●Respiratory failure requiring endotracheal

intubation

●Persistent severe symptoms requiring frequent

nebulized epinephrine dosing

●Underlying conditions placing the child at high risk

for progressive respiratory failure (eg,

neuromuscular disease or bronchopulmonary

dysplasia)

Approximately 8 to 15 percent of children with croup

presenting to the emergency department require

hospitalization; only 1 percent require admission to the

PICU [20,23].

Inpatient management — Children admitted to the

hospital for management of croup should receive close

respiratory monitoring and supportive care.

Supportive care — Supportive care for children

hospitalized with moderate to severe croup includes:

●Fluids − Administration of intravenous fluids may

be necessary in some children. Fever and

tachypnea may increase fluid requirements, and

respiratory difficulty may prevent the child from

achieving adequate oral intake. (See "Maintenance

fluid therapy in children".)

●Fever control − High fever can contribute to

tachypnea and respiratory distress in children with

croup, and treatment with antipyretics can improve

work of breathing and insensible fluid losses.

●Comfort − Care must be taken to avoid provoking

agitation or anxiety in children with moderate to

severe croup as this can worsen the degree of

respiratory distress and airway obstruction. Children

with severe croup should be approached cautiously

and unnecessary invasive interventions should be

avoided. The parent or caregiver should be

instructed to hold and comfort the child and to assist

in care. The use of sedatives or anxiolytics to

reduce agitation is discouraged as this may cause

respiratory depression.

Respiratory care — Respiratory support for children

hospitalized with croup may include the following:

●Nebulized epinephrine − Repeated doses of

nebulized epinephrine may be warranted for

children with moderate to severe distress. It is not

always required; one study of 365 hospitalizations

for croup found that only 49 percent required

additional nebulized epinephrine during the

inpatient stay [24]. Nebulized epinephrine can be

repeated every 15 to 20 minutes. However, children

who require frequent doses of epinephrine (eg,

more frequently than every one to two hours)

should beadmitted/transferred to an intensive care

unit for close cardiopulmonary monitoring.

(See "Croup: Pharmacologic and supportive

interventions", section on 'Nebulized epinephrine'.)

●Supplemental oxygen − Oxygen should be

administered to children who are hypoxemic

(oxygen saturation of <92 percent in room air).

Supplemental oxygen should be humidified to

decrease drying effects on the airways, since drying

may impede the physiologic removal of airway

secretions via mucociliary and cough mechanisms.

(See "Continuous oxygen delivery systems for

infants, children, and adults".)

●Mist − Humidified air is frequently used in the

treatment of croup, although a meta-analysis of

three trials evaluating the use of humidified air in

croup found only marginal improvement in croup

scores [25]. Mist therapy may provide a sense of

comfort and reassurance to both the child and

family; however, if the child is instead agitated by

the mist, it should be discontinued. (See "Croup:

Pharmacologic and supportive interventions",

section on 'Mist therapy'.)

●Heliox − Heliox is a mixture of helium (70 to 80

percent) and oxygen (20 to 30 percent). Heliox may

decrease the work of breathing in children with

croup by reducing turbulent airflow. A meta-analysis

of three trials concluded that while there is evidence

to suggest a short-term benefit of heliox, a larger

trial is needed before recommendations regarding

the use of heliox in children with croup can be made

[26]. While the evidence from these trials does not

suggest a large benefit from Heliox to support its

routine use in the management of croup, in patients

with severe symptoms who are at risk for

respiratory failure, it may be used in an attempt to

avoid the need for intubation. An important limitation

of heliox use is the low fractional concentration of

inspired oxygen (FiO2) in the gas mixture, which

may not be adequate for children with hypoxia.

(See "Croup: Pharmacologic and supportive

interventions", section on 'Heliox'.)

●Intubation − The need for intubation should be

anticipated in children with progressive respiratory

failure so that the procedure can be performed in a

controlled setting if possible. Intubation can be

challenging due to the narrowed subglottic airway

and should be performed with the assistance of a

skilled provider (ie, an anesthesiologist or

otolaryngologist). Neuromuscular blocking agents

should be avoided unless the ability to provide bag-

mask ventilation has been demonstrated. An

endotracheal tube that is 0.5 to 1 mm smaller than

would typically be used should be placed.

(See 'Croup severity score' above and "Emergency

endotracheal intubation in children", section on

'Endotracheal tube'.)

Endotracheal intubation is rarely required for

management of croup. In a large study at one

institution, less than 1 percent of children admitted

to the hospital for croup required intubation [23].

Repeated corticosteroid dosing — Repeat doses of

corticosteroids are not necessary on a routine basis and

may have adverse effects. Moderate to severe symptoms

that persist for more than a few days should prompt

investigation for other causes of airway obstruction.

(See "Croup: Pharmacologic and supportive

interventions", section on 'Repeated dosing' and "Croup:

Clinical features, evaluation, and diagnosis", section on

'Differential diagnosis' and "Assessment of stridor in

children".)

Monitoring — Monitoring should include close

observation of mental status and respiratory status,

including monitoring for stridor, cyanosis, air entry, and

retractions. Pulse oximetry monitoring is useful to detect

hypoxia; however, it is not a sensitive tool for assessing

the severity of croup [22].

Infection control — Children who are admitted to the

hospital with croup should be managed with contact

precautions (ie, gown and gloves for contact), particularly

if parainfluenza or respiratory syncytial virus is the

suspected etiology. If influenza is suspected, droplet

isolation measures (ie, respiratory mask within three feet)

also should be followed. (See "General principles of

infection control".)

Discharge criteria — Children who require hospital

admission may be discharged when they meet the

following criteria:

●No stridor at rest

●Normal pulse oximetry in room air

●Good air exchange

●Normal color

●Normal level of consciousness

●Demonstrated ability to tolerate fluids by mouth

Atypical course — Children admitted for croup typically

remain in the hospital for less than 36 hours [24]. The

child who does not show improvement as expected (over

the course of one to two days) may have an underlying

airway abnormality or may be developing a complication

of croup. Further evaluation with radiographs of the soft

tissues of the neck, or consultation with otolaryngology,

may be warranted. A biphasic illness with poor response

to nebulized epinephrine in conjunction with high fever

and toxic appearance should prompt consideration of

bacterial tracheitis (picture 1) [2]. (See "Croup: Clinical

features, evaluation, and diagnosis", section on

'Differential diagnosis' and "Bacterial tracheitis in

children: Clinical features and diagnosis".)

FOLLOW-UP — Any patient who was admitted to the

hospital, received nebulized epinephrine, or had a

prolonged outpatient visit should have follow-up

scheduled with the primary care provider within 24 hours

or as soon as can be arranged. Although some children

may continue to have mild to moderate symptoms at the

time of follow-up, there are no studies that support the

routine use of corticosteroid therapy beyond 24 hours.

Follow-up should continue until the child's symptoms

have begun to resolve. The child whose symptoms do

not resolve over the course of approximately seven days

may have an underlying airway abnormality or may be

developing a complication of croup. (See 'Atypical

course' above.)

PROGNOSIS — Symptoms of croup resolve in most

children within three days, but may persist for up to one

week [27,28]. Approximately 8 to 15 percent of children

with croup require hospital admission [20,29], and among

those, less than 1 percent require intubation [23].

Mortality is rare, occurring in <0.5 percent of intubated

children [30].

Complications — Complications of croup are

uncommon. Children with moderate to severe croup are

at risk for hypoxemia (oxygen saturation <92 percent in

room air) and respiratory failure. Other complications

include pulmonary edema, pneumothorax, and

pneumomediastinum [31]. These complications can be

anticipated and managed by aggressive monitoring and

intervention in the medical setting. Out-of-hospital cardiac

arrest and death also have been reported [32].

Secondary bacterial infections may arise from croup.

Bacterial tracheitis, bronchopneumonia, and pneumonia

occur in a small number of patients [5,28,33,34]. In most

instances, the child has been relatively stable or

beginning to improve after several days of illness, but

then suddenly worsens, with higher or recurrent fever,

increased (and potentially productive)

cough, and/or respiratory distress. (See "Bacterial

tracheitis in children: Clinical features and diagnosis",

section on 'Clinical features' and"Community-acquired

pneumonia in children: Clinical features and diagnosis",

section on 'Clinical presentation'.)

Recurrent symptoms — Approximately 5 percent of

children treated for croup in the outpatient setting have

repeat visits for recurrent symptoms within seven days

following discharge [20]. Children who have recurrent

episodes of classic viral croup may require radiographic

evaluation or bronchoscopy to evaluate for underlying

airway abnormalities. Recurrent episodes of croup-like

symptoms occurring outside the typical age range for

"viral croup" (ie, six months to three years) and recurrent

episodes that do not appear to be simple "spasmodic

croup" should raise suspicion for large airway lesions,

gastroesophageal reflux or eosinophilic esophagitis, or

atopic conditions [35-40]. (See "Assessment of stridor in

children" and "Croup: Clinical features, evaluation, and

diagnosis", section on 'Spasmodic croup'.)

INFORMATION FOR PATIENTS — UpToDate offers two

types of patient education materials, "The Basics" and

"Beyond the Basics." The Basics patient education

pieces are written in plain language, at the 5th to 6

th grade

reading level, and they answer the four or five key

questions a patient might have about a given condition.

These articles are best for patients who want a general

overview and who prefer short, easy-to-read materials.

Beyond the Basics patient education pieces are longer,

more sophisticated, and more detailed. These articles are

written at the 10th to 12

th grade reading level and are best

for patients who want in-depth information and are

comfortable with some medical jargon.

Here are the patient education articles that are relevant

to this topic. We encourage you to print or e-mail these

topics to your patients. (You can also locate patient

education articles on a variety of subjects by searching

on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient information: Croup

(The Basics)")

●Beyond the Basics topics (see "Patient

information: Croup in infants and children (Beyond

the Basics)")

SUMMARY AND RECOMMENDATIONS

●Children with croup should be seen in the office or

emergency department if they have stridor at rest,

an underlying airway abnormality, previous

episodes of moderate to severe croup, underlying

conditions that may predispose to respiratory

failure, rapid progression of symptoms, inability to

tolerate fluids, prolonged symptoms, or an atypical

course. (See 'Telephone triage' above.)

●Children with mild symptoms (ie, no stridor at rest

and no respiratory distress) can be managed at

home. Families should be instructed in provision of

supportive care and indications to seek medical

attention. (See 'Home treatment' above.)

●We suggest that a single dose of

oral dexamethasone (0.6 mg/kg) be used when

electing to treat children with mild croup who are

seen in the outpatient setting (algorithm 1) (Grade

2A). (See 'Outpatient treatment' above and "Croup:

Pharmacologic and supportive interventions",

section on 'Dexamethasone'.)

●Children with moderate croup (ie, stridor at rest

with mild to moderate retractions) should be

evaluated in the office or emergency department,

and those with severe croup (stridor at rest with

marked retractions and significant distress or

agitation) should be evaluated in the emergency

department (table 1). Children with severe croup

must be approached cautiously, as any increase in

anxiety may worsen airway obstruction.

(See 'Moderate to severe croup' above.)

●We recommend that children with moderate to

severe croup be treated with a single dose

of dexamethasone (0.6 mg/kg, maximum of 10 mg)

by the least invasive route (algorithm 1) (Grade

1A). (See 'Initial treatment' above and "Croup:

Pharmacologic and supportive interventions",

section on 'Glucocorticoids'.)

●We recommend that children with moderate to

severe croup be treated with

nebulized epinephrine (Grade 1A) in addition

to dexamethasone (algorithm 1). (See'Initial

treatment' above and "Croup: Pharmacologic and

supportive interventions", section on 'Nebulized

epinephrine'.)

•Racemic epinephrine is administered as

0.05 mL/kg per dose (maximum of 0.5 mL) of

a 2.25 percent solution diluted to 3 mL total

volume with normal saline. It is given via

nebulizer over 15 minutes.

•L-epinephrine is administered as

0.5 mL/kg per dose (maximum of 5 mL) of a

1:1000 dilution. It is given via nebulizer over

15 minutes.

Nebulized epinephrine can be repeated every 15 to

20 minutes. The administration of three or more

doses within a two- to three-hour time period should

prompt initiation of close cardiac monitoring if this is

not already underway.

●Children with moderate to severe croup should be

observed for three to four hours after intervention.

Those who improve may be discharged home.

Children with persistent or worsening symptoms

during the observation period should be admitted to

the hospital. (See 'Discharge to home' above

and 'Indications for hospital admission' above.)

●Management of children hospitalized for croup

includes:

•Supportive care with provision of intravenous

fluids and fever reduction. (See 'Supportive

care' above.)

•Respiratory care with repeated doses of

nebulized epinephrine, as indicated by

respiratory distress, and administration of

humidified air or oxygen, as indicated by

hypoxemia. (See 'Respiratory care' above.)

•Monitoring for worsening respiratory distress.

(See 'Monitoring' above.)

We suggest not using repeated doses of

corticosteroids (Grade 2C). (See 'Repeated

corticosteroid dosing' above and "Croup:

Pharmacologic and supportive interventions",

section on 'Repeated dosing'.)

●Children who have moderate to severe symptoms

that persist for more than a few days, or recurring

episodes of croup not associated with other

manifestations of a viral illness (no

fever and/or rhinorrhea) should undergo

investigation for other causes of upper airway

obstruction. (See 'Atypical course' above

and 'Recurrent symptoms' above and "Croup:

Clinical features, evaluation, and diagnosis", section

on 'Differential diagnosis'.)

●Children who received nebulized epinephrine, had

a prolonged outpatient visit, or were admitted to the

hospital should have follow-up scheduled with the

primary care provider within 24 hours of discharge

or as soon as follow-up can be arranged. Most

children with croup recover uneventfully.

(See 'Follow-up' above and 'Prognosis'above.)

Use of UpToDate is subject to the Subscription and License Agreement.

REFERENCES

1. Westley CR, Cotton EK, Brooks JG. Nebulized racemic epinephrine by IPPB for the treatment of croup: a double-blind study. Am J Dis Child 1978; 132:484.

2. Alberta Clinical Practice Guidelines Guideline Working Group. Guidelines for the diagnosis and management of croup. www.topalbertadoctors.org/download/252/croup_guideline.pdf (Accessed on March 13, 2015).

3. Cherry JD. Clinical practice. Croup. N Engl J Med 2008; 358:384.

4. Clarke M, Allaire J. An evidence-based approach to the evaluation and treatment of croup in children. Pediatric Emergency Medicine Practice 2012; 9:1.

5. Fleisher G. Infectious disease emergencies. In: Textbook of Pediatric Emergency Medicine, 5th ed, Fleisher GR, Ludwig S, Henretig FM (Eds), Lippincott, Williams & Wilkins, Philadelphia 2006. p.783.

6. Geelhoed GC, Turner J, Macdonald WB. Efficacy of a small single dose of oral dexamethasone for outpatient croup: a double blind placebo controlled clinical trial. BMJ 1996; 313:140.

7. Bjornson CL, Klassen TP, Williamson J, et al. A randomized trial of a single dose of oral dexamethasone for mild croup. N Engl J Med 2004; 351:1306.

8. Klassen TP, Craig WR, Moher D, et al. Nebulized budesonide and oral dexamethasone for treatment of croup: a randomized controlled trial. JAMA 1998; 279:1629.

9. Paul RI. Oral dexamethasone for croup (commentary). AAP Grand Rounds 2004; 12:67.

10. Duggan DE, Yeh KC, Matalia N, et al. Bioavailability of oral dexamethasone. Clin Pharmacol Ther 1975; 18:205.

11. Johnson DW, Jacobson S, Edney PC, et al. A comparison of nebulized budesonide, intramuscular dexamethasone, and placebo for moderately severe croup. N Engl J Med 1998; 339:498.

12. Russell KF, Liang Y, O'Gorman K, et al. Glucocorticoids for croup. Cochrane Database Syst Rev 2011; :CD001955.

13. Bjornson C, Russell K, Vandermeer B, et al. Nebulized epinephrine for croup in children. Cochrane Database Syst Rev 2013; 10:CD006619.

14. Prendergast M, Jones JS, Hartman D. Racemic epinephrine in the treatment of laryngotracheitis: can we identify children for outpatient therapy? Am J Emerg Med 1994; 12:613.

15. Ledwith CA, Shea LM, Mauro RD. Safety and efficacy of nebulized racemic epinephrine in conjunction with oral

dexamethasone and mist in the outpatient treatment of croup. Ann Emerg Med 1995; 25:331.

16. Kunkel NC, Baker MD. Use of racemic epinephrine, dexamethasone, and mist in the outpatient management of croup. Pediatr Emerg Care 1996; 12:156.

17. Rizos JD, DiGravio BE, Sehl MJ, Tallon JM. The disposition of children with croup treated with racemic epinephrine and dexamethasone in the emergency department. J Emerg Med 1998; 16:535.

18. Waisman Y, Klein BL, Boenning DA, et al. Prospective randomized double-blind study comparing L-epinephrine and racemic epinephrine aerosols in the treatment of laryngotracheitis (croup). Pediatrics 1992; 89:302.

19. Fitzgerald D, Mellis C, Johnson M, et al. Nebulized budesonide is as effective as nebulized adrenaline in moderately severe croup. Pediatrics 1996; 97:722.

20. Rosychuk RJ, Klassen TP, Metes D, et al. Croup presentations to emergency departments in Alberta, Canada: a large population-based study. Pediatr Pulmonol 2010; 45:83.

21. Brown JC. The management of croup. Br Med Bull 2002; 61:189.

22. Petrocheilou A, Tanou K, Kalampouka E, et al. Viral croup: diagnosis and a treatment algorithm. Pediatr Pulmonol 2014; 49:421.

23. Dobrovoljac M, Geelhoed GC. 27 years of croup: an update highlighting the effectiveness of 0.15 mg/kg of dexamethasone. Emerg Med Australas 2009; 21:309.

24. Narayanan S, Funkhouser E. Inpatient hospitalizations for croup. Hosp Pediatr 2014; 4:88.

25. Moore M, Little P. Humidified air inhalation for treating croup. Cochrane Database Syst Rev 2006; :CD002870.

26. Moraa I, Sturman N, McGuire T, van Driel ML. Heliox for croup in children. Cochrane Database Syst Rev 2013; 12:CD006822.

27. Thompson M, Vodicka TA, Blair PS, et al. Duration of symptoms of respiratory tract infections in children: systematic review. BMJ 2013; 347:f7027.

28. Cherry JD. Croup (laryngitis, laryngotracheitis, spasmodic croup, laryngotracheobronchitis, bacterial tracheitis, and laryngotracheobronchopneumonitis) and epiglottitis

(supraglottitis). In: Feigin and Cherry’s Textbook of Pediatric Infectious Diseases, 7th ed, Cherry JD, Harrison GJ, Kaplan SL, et al (Eds), Elsevier Saunders, Philadelphia 2014. p.241.

29. Johnson D. Croup. Clin Evid 2005; :310. 30. McEniery J, Gillis J, Kilham H, Benjamin B. Review of

intubation in severe laryngotracheobronchitis. Pediatrics 1991; 87:847.

31. Travis KW, Todres ID, Shannon DC. Pulmonary edema associated with croup and epiglottitis. Pediatrics 1977; 59:695.

32. Fisher JD. Out-of-hospital cardiopulmonary arrest in children with croup. Pediatr Emerg Care 2004; 20:35.

33. Sofer S, Dagan R, Tal A. The need for intubation in serious upper respiratory tract infection in pediatric patients (a retrospective study). Infection 1991; 19:131.

34. Rosekrans JA. Viral croup: current diagnosis and treatment. Mayo Clin Proc 1998; 73:1102.

35. Cooper T, Kuruvilla G, Persad R, El-Hakim H. Atypical croup: association with airway lesions, atopy, and esophagitis. Otolaryngol Head Neck Surg 2012; 147:209.

36. Duval M, Tarasidis G, Grimmer JF, et al. Role of operative airway evaluation in children with recurrent croup: a retrospective cohort study. Clin Otolaryngol 2015; 40:227.

37. Delany DR, Johnston DR. Role of direct laryngoscopy and bronchoscopy in recurrent croup. Otolaryngol Head Neck Surg 2015; 152:159.

38. Rankin I, Wang SM, Waters A, et al. The management of recurrent croup in children. J Laryngol Otol 2013; 127:494.

39. Jabbour N, Parker NP, Finkelstein M, et al. Incidence of operative endoscopy findings in recurrent croup. Otolaryngol Head Neck Surg 2011; 144:596.

40. Chun R, Preciado DA, Zalzal GH, Shah RK. Utility of bronchoscopy for recurrent croup. Ann Otol Rhinol Laryngol 2009; 118:495.

Topic 6004 Version 11.0

Croup: Pharmacologic and supportive interventions Author Charles R Woods, MD, MS Section Editor Sheldon L Kaplan, MD Deputy Editor Carrie Armsby, MD, MPH Disclosures: Charles R Woods, MD, MS Other Financial Interest: Cerexa [Epiglottitis (Data Safety Monitoring Board for pediatric trials of the antibiotic agent ceftaroline)]. Sheldon L Kaplan, MDGrant/Research/Clinical Trial Support: Pfizer [vaccine (PCV13)]; Forest Lab [antibiotic (Ceftaroline)]; Optimer [antibiotic (fidaxomicin)]. Consultant/Advisory Boards: Pfizer [vaccine (PCV13)]. Carrie Armsby, MD, MPH Nothing to disclose.

Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence.

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All topics are updated as new evidence becomes available and our peer review process is complete. Literature review current through: Jul 2015. | This topic last updated: Jan 30, 2014.

INTRODUCTION — Croup (laryngotracheitis) is a

respiratory illness characterized by inspiratory stridor,

barking cough, and hoarseness. It typically occurs in

children six months to three years of age and is caused

by parainfluenza virus. (See "Croup: Clinical features,

evaluation, and diagnosis".)

The treatment of croup has changed significantly since

the 1980s. Glucocorticoids and

nebulized epinephrine have become the cornerstones of

therapy. Substantial clinical evidence supports the

efficacy of these interventions [1-5]. The impact also is

evident in the decrease in annual hospital admissions for

croup in children in the United States between 1979 to

1982 and 1994 to 1997 (from 2.8 to 2.1 per 1000 for

children <1 year and from 1.8 to 1.2 per 1000 children

for children 1 to 4 years) [6].

Treatment of croup may involve a variety of

pharmacologic and nonpharmacologic interventions. It

may occur entirely at home, or in the office, emergency

department (ED), or hospital setting. Supportive and

pharmacologic interventions will be discussed below.

The clinical features and evaluation of croup and the

approach to management are discussed separately.

(See "Croup: Clinical features, evaluation, and

diagnosis" and "Croup: Approach to management".)

GLUCOCORTICOIDS — Glucocorticoids provide long-

lasting and effective treatment of mild, moderate, and

severe croup [3,7-9]. The antiinflammatory actions of

glucocorticoids are thought to decrease edema in the

laryngeal mucosa of children with croup. Improvement is

usually evident within six hours of administration but

seldom is dramatic [7,10].

Treatment with glucocorticoids at various doses and by

various routes has been shown to improve croup scores

and to decrease unscheduled medical visits, length of

stay in the emergency department or hospital, and the

use of epinephrine [7]. Among the available

glucocorticoids, dexamethasone has been used most

frequently, is the least expensive, has the longest

duration of action, and is the easiest to administer.

Efficacy — Intramuscular (IM), intravenous (IV), oral,

and inhaled routes of administration of glucocorticoids

have been shown to be effective in croup of all levels of

severity [7,8]. Dexamethasone (oral or IM)

and budesonide (inhaled) were the agents used in the

majority of studies. A systematic review included 24

trials (with collective enrollment of 2878 children) that

objectively measured the effectiveness of glucocorticoid

treatment for croup compared with placebo [7]. Fourteen

other trials compared different glucocorticoid agents or

different routes or dosages of the same agent [7].

Compared with treatment with placebo, treatment with

glucocorticoid was associated with:

●Improvement in the croup score at six hours with

a weighted mean difference of -1.2 (95% CI -1.6 to

-0.8) and at 12 hours -1.9 (95% CI -2.4 to -1.3); at

24 hours this improvement was no longer

significant (-1.3, 95% CI -2.7-0.2)

●Fewer return visits and/or (re)admissions (relative

risk 0.50, 95% CI 0.3-0.7)

●Decreased length of time spent in emergency

department or hospital (weighted mean difference

12 hours, 95% CI 5-19 hours)

●Decreased use of epinephrine (risk difference 10

percent; 95% CI 1-20 percent)

●There were no significant differences in clinical

efficacy between the routes or agents, and the

combination of oral or IM dexamethasone with

inhaled budesonidewas not superior to either agent

alone [11,12].

Another systematic review of eight randomized

controlled trials compared the administration of

nebulized glucocorticoids with placebo. Children treated

with nebulized glucocorticoids were significantly more

likely to show improvement in croup score at five hours

(combined relative risk (RR) 1.48, 95% CI 1.27-1.74)

and significantly less likely to need hospital admission

(combined RR 0.56, 95% CI 0.42-0.75) [13].

Adverse effects — Few serious adverse effects have

been reported in the studies evaluating the efficacy of

a single dose of glucocorticoids in croup [14]. However,

most of these studies were too small to sufficiently

evaluate rare (<1 percent) adverse effects [15,16].

The primary concern is potential risk of progressive viral

infection or secondary bacterial infection, which have

been reported in patients who received glucocorticoid

treatment over several days [16], or received

nebulized dexamethasone and had neutropenia [17].

These complications have not been described in children

who have received single doses of oral, intramuscular,

or intravenous glucocorticoids for croup.

Glucocorticoid use may exacerbate active varicella and

tuberculosis and should be avoided in children with

these infections and in those recently exposed to, and

possibly incubating, varicella [18,19]. (See "Clinical

features of varicella-zoster virus infection:

Chickenpox" and "Treatment of varicella-zoster virus

infection: Chickenpox".)

Administration of glucocorticoids may mask the

presentation of steroid-responsive upper airway lesions,

such as hemangiomas, which also can present with

stridor, particularly during a viral upper respiratory tract

infection [20]. (See "Epidemiology, pathogenesis, clinical

features, and complications of infantile hemangiomas".)

Agents

Dexamethasone — Dexamethasone may be

administered IM, IV, or orally. To date, no clinically

significant difference in croup outcomes between IM or

orally administered dexamethasone has been

demonstrated [7]. When dexamethasone is administered

IM or IV, a single dose of 0.6 mg/kg (maximum dose of

10 mg) is used most frequently. Smaller doses appear to

be equally effective for mild croup when administered

orally, as illustrated below:

●In one study, 100 children with mild croup were

randomly assigned to receive

oral dexamethasone (0.15 mg/kg) or placebo in the

emergency department [21]. Eight children in the

placebo group, and none in the dexamethasone

group, returned for medical care (a statistically

significant difference).

●In another study, 120 hospitalized children with

croup were randomly assigned to receive a single

oral dose

of dexamethasone (0.15 mg/kg, 0.3 mg/kg, 0.6 mg/

kg) or placebo [22]. There was no difference in

duration of hospitalization, reduction in croup

score, or epinephrine use among the three groups

receiving dexamethasone.

The second study described above [22] included a small

number of children with relatively mild croup and

consequently may have been underpowered (unable) to

detect a clinically important difference, particularly in

children with more severe symptoms [14].

Children with mild croup who can tolerate oral

medications can be given

either dexamethasone 0.15 mg/kg or dexamethasone

0.6 mg/kg orally, to a maximum total dose of 10 mg.

Although the lower 0.15 mg/kg dose appears to be

efficacious [21], we continue to suggest the higher dose

[23,24].

The oral preparation of dexamethasone (1 mg per mL)

has a foul taste. The intravenous preparation is more

concentrated (4 mg per mL) and can be given orally

mixed with syrup [11,25,26].

Studies of nebulized dexamethasone in children with

croup have mixed results. One study found nebulized

dexamethasone to be less effective than oral

dexamethasone in preventing the need for subsequent

treatment with glucocorticoid or epinephrine in children

with mild croup [27]. Another study found that treatment

with nebulized dexamethasone in children with moderate

croup improved croup scores at four hours but did not

affect the rate of hospitalization [17]. In addition, two

patients with neutropenia who were treated with

dexamethasone developed bacterial tracheitis.

Budesonide — Nebulized budesonide has been shown

to be more effective than placebo and as effective as IM

or oral dexamethasone for the treatment of croup [7,28].

However, nebulized budesonide is more expensive and

more difficult to administer than IM or oral

dexamethasone and is not routinely indicated in the

treatment of croup. However, nebulized budesonide may

provide an alternative to IM or IV dexamethasone for

children with vomiting or severe respiratory distress [24].

In children with severe respiratory distress, a single dose

of budesonide may be mixed with epinephrine and

administered simultaneously. (See "Croup: Approach to

management", section on 'Moderate to severe croup'.)

Prednisolone — Some authorities suggest that for

children who are treated as outpatients,

oral prednisolone (2 mg/kg per day for three days) is an

alternative to oraldexamethasone [29]. The use of

prednisolone in the treatment of croup has been

evaluated in a limited number of studies.

A 2011 meta-analysis of two trials [30,31] that compared

a single dose of oral dexamethasone (0.6 mg/kg or

0.15 mg/kg) with a single dose of

oral prednisolone (1 mg/kg)showed no difference in

croup scores, but children randomized to receive

dexamethasone had fewer return

visits and/or subsequent admissions (9.6 versus 29.7

percent, RR 0.3, 95% CI 0.2-0.6) [7].

A subsequent randomized trial compared

oral dexamethasone (0.6 mg/kg on the first day followed

by placebo on the next two days) with

oral prednisolone (2 mg/kg per day for three days) in 87

children with mild or moderate croup who were treated

as outpatients [29]. There were no differences between

groups in additional health care visits (2 versus 7

percent [not significant]), duration of symptoms (2.8

versus 2.2 days), duration of nonbarky cough (6.1

versus 5.9 days), nights with disturbed parental sleep

(0.7 versus 1.2), or days with stress (1.6 versus 1.4).

Another study of 70 children

compared prednisolone (1 mg/kg every 12 hours) with

placebo in children with croup who were already

intubated [8]. Children who received prednisolone had a

shorter median duration of intubation than those in the

placebo group (98 versus 138 hours). In addition, fewer

children in the prednisolone group required reintubation

(5 versus 34 percent).

Prednisone — The use of prednisone in the

management of croup has not been evaluated in clinical

trials. However, it has equivalent potency

to prednisolone and, in theory, should have similar

effects. Despite its lack of proven benefit, prednisone is

widely used in the outpatient management of croup [32].

If prednisone is to be used, it is important to administer a

dose that is equivalent in strength to the doses of

glucocorticoids that have been better

studied. Dexamethasonehas 6.67 times the

glucocorticoid potency of prednisone (4 mg/kg of

prednisone = 0.6 mg/kg of dexamethasone; 2 mg/kg of

prednisone = 0.3 mg/kg of dexamethasone; and

1 mg/kg of prednisone = 0.15 mg/kg of dexamethasone).

If choosing to use the higher dose (ie, 4 mg/kg of

prednisone), the volume required may be prohibitive

given that the concentration of the oral solution of

prednisone is 1 mg/1 mL.

Betamethasone — A pilot study compared the

effectiveness of a single oral dose

of betamethasone (0.4 mg/kg) with a single dose of

IM dexamethasone (0.6 mg/kg)in 52 children (six months

to six years) with mild to moderate croup who were

treated in the emergency department [33]. Despite

randomization, mean baseline croup scores were higher

in the dexamethasone group (3.6 versus 2). Croup

scores declined significantly in both groups, and there

were no differences between groups in mean croup

scores four hours after treatment, rate of hospitalization,

time to resolution of symptoms, need for additional

treatment, or number of return visits to the emergency

department.

Repeated dosing — The majority of clinical trials of oral

and IM glucocorticoids in croup have used a single dose.

Repeat doses are not necessary on a routine basis.

Although repeat doses may be reasonable in the

occasional child who has persistent symptoms, they

should be used with caution. The anecdotal cases of

progression of viral illness and secondary bacterial

infection that have been reported with use of

glucocorticoids for croup occurred with repeated dosing

over several days [34], or in neutropenic patients [17].

(See 'Adverse effects' above.)

Moderate to severe symptoms that persist for more than

a few days should prompt investigation for other causes

of airway obstruction. (See "Croup: Clinical features,

evaluation, and diagnosis", section on 'Differential

diagnosis'.)

NEBULIZED EPINEPHRINE — The administration of

nebulized epinephrine to patients with moderate to

severe croup often results in rapid improvement of upper

airway obstruction. Epinephrine constricts precapillary

arterioles in the upper airway mucosa and decreases

capillary hydrostatic pressure, leading to fluid resorption

and improvement in airway edema [18]. Even a modest

increase in airway diameter can lead to significant

clinical improvement.

Benefits — Several small randomized controlled trials

and a meta-analysis have demonstrated the benefit of

racemic epinephrine compared with placebo in reducing

the croup scores 30 minutes after treatment in children

in the emergency department, hospital, and intensive

care unit [1,35-37]. The magnitude of reduction in mean

croup score from baseline ranged from 2.2 to 3.6 at 20

to 30 minutes (compared with approximately 1 in the

placebo group). However, by 120 minutes, croup scores

returned to baseline or near baseline [1,36]. In one trial,

treatment with IM dexamethasone and nebulized

epinephrine was associated with decreased duration of

hospitalization compared with IM dexamethasone and

placebo (-32 hours, 95% CI -59.1 to -4.9) [38,39].

Administration of epinephrine does not alter the natural

history of croup in the short (>2 hours) or longer term (24

to 36 hours) [1,36,39].

In the studies described above, racemic epinephrine was

administered either by nebulization alone or by

nebulization combined with intermittent positive pressure

breaths [1,35,36]. Another study compared these two

methods of administration and found them to be similarly

effective [2].

Racemic versus L-epinephrine —

Racemic epinephrine, which is a 1:1 mixture of the D-

and L-isomers, was initially thought to produce fewer

systemic side effects, such as tachycardia and

hypertension [18]. However, a randomized double-blind

study comparing racemic epinephrine and L-epinephrine

in children with croup found no difference between the

two preparations in 30-minute croup score, heart rate,

blood pressure, respiratory rate, fraction of inspired

oxygen, or oxygen saturation [40]. This finding is

particularly important outside of the United States, where

racemic epinephrine is not readily available. Either form

of epinephrine is acceptable to use in the United States.

Dose

●Racemic epinephrine is administered as

0.05 mL/kg per dose (maximum of 0.5 mL) of a

2.25 percent solution diluted to 3 mL total volume

with normal saline. It is given via nebulizer over 15

minutes.

●L-epinephrine is administered as 0.5 mL/kg per

dose (maximum of 5 mL) of a 1:1000 dilution [40].

It is given via nebulizer over 15 minutes.

Nebulized epinephrine treatments may be repeated

every 15 to 20 minutes if warranted by the clinical

course. Children who require repeated frequent dosing

(eg, three or more doses within two to three hours) to

achieve stabilization of their respiratory function

generally should be admitted to an intensive care unit or

intermediate care setting (depending on the severity of

persisting signs).

Precautions — The clinical effects of

nebulized epinephrine last for no more than two hours.

After the effects have worn off, symptoms may return to

baseline (an apparent worsening, sometimes referred to

as the "rebound phenomenon"). Children who receive

even a single dose of nebulized epinephrine should be

observed in the emergency department or hospital

setting for at least three to four hours after administration

to ensure that symptoms do not return to baseline.

Serious adverse effects from nebulized epinephrine are

exceedingly rare. However, a case of myocardial

infarction in a child with croup who received three doses

of racemic epinephrine within 60 minutes has been

reported [41]. Thus, it seems prudent to place children

who require ongoing epinephrine treatments more

frequently than every one to two hours on cardiac

monitors (both because of the severity of illness and the

potential systemic impact of nebulized epinephrine).

Continuous electrocardiographic monitoring (or

equivalent cardiac monitoring) also should be

considered in these cases.

OXYGEN — Oxygen is not known to have any direct

impact on the subglottic edema or airway narrowing, but

should be administered to children who are hypoxemic

(oxygen saturation of <92 percent in room air) and/or in

moderate to severe respiratory distress [14,24].

Supplemental oxygen should be humidified to decrease

drying effects on the airways, since drying may impede

the physiologic removal of airway secretions via

mucociliary and cough mechanisms. (See "Continuous

oxygen delivery systems for infants, children, and

adults".)

Heliox — Helium is inert, nontoxic, and of very low

density. Heliox is a mixture of helium (70 to 80 percent)

and oxygen (20 to 30 percent). It can flow through

airways with less turbulence and resistance than pure

oxygen. (See "Physiology and clinical use of heliox".)

Heliox decreases the work of respiration in children with

croup and theoretically could be used as a temporizing

measure, to prevent the need for intubation while waiting

for glucocorticoids to decrease airway edema [42].

However, in clinical trials, heliox has not definitively been

shown to be more effective than humidified oxygen or

racemic epinephrine in reducing croup scores [43-45]. A

2013 systematic review found only three

methodologically limited trials (91 patients) evaluating

heliox in children with croup and concluded that a larger

trial is needed before recommendations regarding the

use of heliox in children with croup can be made [45].

MIST THERAPY — Humidified air is frequently used in

the treatment of croup, although there have been no

studies supporting its efficacy in reducing symptoms

[46]. Two randomized trials (one comparing mist versus

no mist and the other comparing no mist, low humidity,

and 100 percent humidity) among children brought to an

emergency department for croup demonstrated no

significant change in croup scores from baseline

between the groups [47,48].

Although humidified air does not reduce subglottic

edema, it may provide other benefits. Inhalation of moist

air, relative to dry air, may decrease drying of inflamed

mucosal surfaces and reduce inspissation of secretions

[49]. In addition, a mist source may provide a sense of

comfort and reassurance to both the child and family

[50-52]. In medical settings, mist therapy may be

provided by blow-by or saline nebulization treatments.

Croup tents should be avoided, since they can

aggravate a child's anxiety and make vital signs and

other visual assessments of the child more difficult.

Some guidelines recommend against the use of mist

therapy for children who are hospitalized with croup [24].

Certainly if the child is agitated by the provision of mist,

mist therapy should be discontinued.

OTHER THERAPIES

Antibiotics — Antibiotics have no role in the routine

management of uncomplicated croup, since most cases

are caused by viruses [14]. Antibiotics should be used

only to treat specific bacterial complications, such as

tracheitis.

Antitussives — Nonprescription antitussive agents are

of unproven benefit for croup (or other respiratory tract

infections). Codeine, which is a more potent cough

suppressant, can alter the child's sensorium, making it

difficult to follow the clinical course.

Decongestants — Decongestants also are of unproven

benefit for croup [14,24].

Sedatives — The routine use of sedative agents in effort

to improve airway obstruction by relieving anxiety and

apprehension is not recommended. Sedatives may treat

the symptom of agitation while masking the underlying

causes of air hunger and hypoxia. They also may

decrease respiratory effort (and therefore croup scores),

without improving ventilation [14,53].

INFORMATION FOR PATIENTS — UpToDate offers

two types of patient education materials, “The Basics”

and “Beyond the Basics.” The Basics patient education

pieces are written in plain language, at the 5th to

6th grade reading level, and they answer the four or five

key questions a patient might have about a given

condition. These articles are best for patients who want

a general overview and who prefer short, easy-to-read

materials. Beyond the Basics patient education pieces

are longer, more sophisticated, and more detailed.

These articles are written at the 10th to 12

th grade

reading level and are best for patients who want in-depth

information and are comfortable with some medical

jargon.

Here are the patient education articles that are relevant

to this topic. We encourage you to print or e-mail these

topics to your patients. (You can also locate patient

education articles on a variety of subjects by searching

on “patient info” and the keyword(s) of interest.)

●Basics topic (see "Patient information: Croup (The

Basics)")

●Beyond the Basics topic (see "Patient information:

Croup in infants and children (Beyond the Basics)")

SUMMARY

●Treatment with glucocorticoids (oral,

intramuscular, or nebulized) has been shown to

decrease croup scores, unscheduled medical

visits, length of stay in the emergency department

or hospital, and the use of epinephrine. A single

dose of oral or intramuscular dexamethasone is

appropriate and adequate for most children.

(See 'Glucocorticoids' above and "Croup: Approach

to management", section on 'Initial treatment'.)

●Treatment with nebulized epinephrine results in

rapid improvement of upper airway obstruction, but

the duration of effect is less than two hours.

Racemic epinephrine and L-epinephrine appear to

be equally effective. (See 'Nebulized

epinephrine' above.)

●Humidified air is frequently used as a supportive

treatment for croup; however, there have been no

studies supporting its efficacy in reducing

symptoms. (See 'Mist therapy' above.)

●Humidified oxygen should be administered to

children who are hypoxemic and/or in moderate to

severe respiratory distress. (See 'Oxygen' above.)

●Heliox has not definitively been shown to be more

effective than humidified oxygen or

racemic epinephrine in reducing croup scores.

(See 'Heliox' above.)

●Antibiotics should be used only to treat specific

bacterial complications of croup.

(See 'Antibiotics' above and "Croup: Approach to

management", section on 'Complications'.)

●Antitussives and decongestants are of unproven

benefit in the management of croup. Sedatives

may decrease the work of breathing and improve

agitation without actually improving ventilation or

addressing the underlying cause of agitation

(hypoxemia). (See 'Other therapies' above.)

Use of UpToDate is subject to the Subscription and License Agreement.

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