meningococcal infections
TRANSCRIPT
•Meningococcal nasopharyngitis•Meningococcemia•Meningitis
Charan TejasviML-510
Neisseria meningitidis (meningococcus)
gm (-) diplococcus usually found within PMN leucocytes
found only in man
13 serogroups by surface capsular polysaccharide
A, B, C, W135 and Y- frequent isolates from patients with meningococcal disease
Other groups isolated from carriers
Meningococcal Infections
Common in temperate and tropical climates
carriage rates: healthy children 2-5% military personnel (epidemics) 90%
transmitted via contact with respiratory secretions
Meningococcal Infections
Disease may occur following exposure to carriers or infected patients within the family, day care and military camps
occurs most frequent:(< 5 yrs old ) peak attack rate : 6-12 months old
2nd peak attack rate: 15-19 y/o of age
Meningococci colonize the nasopharynx penetrate mucosal surface transported by leukocytes to blood stream hematogenous dissemination localizes: heart, CNS, skin, mucous and serous membranes adrenals
Release of IL and TNF
hypotension multi-organ system failure
Diffusevasculitis
*Complement activation
DIC
H’ge and necrosis in any organ bleeding into adrenals in patients with septicemia and shock
Waterhouse- Friderichsen syndrome
Clinic. The incubation period is from 2 to 10 days (usually 4-6 days).
Clinical classification:Localized forms (acute
nasopharyngitis)Generalized forms
(meningococcemia, meningitis)Rare form (endocarditis, arthritis,
pneumonia, iridocyclitis)
spectrum range from asx’c colonization to fulminant sepsis
1. Bacteremia without sepsis 2. Meningococcemia (sepsis) without
meningitis
3. Meningitis with or without meningococcemia
Manifested a moderate and short-term (1-3 days)
increase in temperature, mild symptoms of intoxication rhinopharyngitis (nasal congestion,
flushing, dryness, swelling of the posterior pharyngeal wall with hyperplasia of lymphoid follicles affected mucosa "dry", sometimes bluish).
From acute viral disease meningococcal nasopharyngitis different is that the mucous membrane of the soft and hard palate, and tonsils are not impaired or only slightly hyperaemic, but major changes are located on the back of the throat.
Nasopharyngitis preceded meningococcemia at an average of 78% of patients.
Meningococcemia is inherently meningococcal sepsis, which, like other septic conditions, appears febrile fever and severe intoxication syndrome with manifestations of multiple organ pathology.
The most important diagnostic symptom is a “RASH”.
after 5-15 hours of onset single or multiple polymorphic
elements ranging in size from 2.1 mm to 5 cm or more in diameter and has a hemorrhagic character.
asymmetrically, mainly on the skin of the thighs and buttocks, at least - on the trunk and face.
Eruptions have different colors - red, brown, yellowish-green. In the center of the elements of necrotizing rash. Most often appear large star-shaped form of hemorrhagic lesions with dense infiltrated the base and necrosis in the center.
Initially with pharyngitis, fever, myalgias, arthralgias, headache, and GI complaints within hours--> (+) petechial, purpuric (purpura fulminanas)
( slate gray satellite shaped ) or morbilliform lesions with hypotension, DIC, acidosis,
adrenal h’ge, renal/heart failure, coma
If fulminant--> rapidly progressive purpura, relentless shock, adrenal H’ge, extensive
hematogenous dissemination unresponsive
to therapy
if with meningitis, (most common clinical manifestation) indistinguishable from those
2° to other bacteria
(+) petechial < 12° prior to admission (+) hypotension absence of meningitis WBC < 10,000/mm3 ESR < 10 mm/hr.
Interpretation: (+) 3 or > features: 90% mortality > 2 features; 9% mortality
Rapid progression of petechia to ecchymoses or purpura Wakefulness skin perfusion respiratory distress thrombocytopenia advanced age
Seen in children and adults
low grade fever, non toxic appearance, arthralgias, headache , rash,
(+) blood culture
mean duration of illness: 6-8 weeks
Waxing and waning sx purulent arthritis acute non suppurative polyarthritis erythema nodosum URI subacute endocarditis
assoc with C5 deficiency
Chronic Meningococcemia
1. Maintain a high index of suspicion (fever, petechial rash, abn mental status)
2. Gm stain of petechial scrapings CSF buffy coat of blood; gm (-) diplococci
3. Culture of blood, CSF, petechial scraping, synovial
fluid, sputum and other body fluids
4. Antigen detection tests (CSF, urine, serum) CIE, latex agglutination, lack adequate sensitivity and specificity
Aq Penicillin G 250,000 -300,000 u/k/day IV 6 div doses x 7 days Alternatives : Cefotaxime 200 mg/k/d Ceftriazone 100-150 mg/k/day
If allergic to B-lactams : Chloramphenicol 75-100 mg/kg d
ISOLATION: RESPIRATORY isolation until 24° after effective antibiotics
Chemoprophylaxis
for all household, school or day care contacts ASAP or within 24° from diagnosis of 1° case
NOT ROUTINELY recommended for medical personnel EXCEPT those with INTIMATE exposure (mouth to mouth resuscitation, intubation, suctioning)
Chemoprophylaxis DOC: Rifampicin 10 mg/kg (max 600 mg) q
12° x 2 days
other drugs: Ceftriaxone Ciprofloxacin
meningococcal vaccine can be used with chemoprophylaxis since 2° cases may occur several weeks later
Vaccines available monovalent A bivalent A and C quadrivalent A, C, Y, W135
no effective vaccine against serogroup B
not routinely recommended
Recommended: 1. children > 2 yrs.
2. In high risk grps.
(+) functional /anatomic asplenia,
(+) terminal complement component defect +
as adjunct to chemoprophylaxis
For Meningitis: deafness ataxia Sz blindness paresis of CN 3,4,6,7, hemi or quadriparesis obstructive hydrocephalus
Complications
For Meningococcemia: Adrenal H’ge, arthritis, myocarditis, pericarditis, pneumonia, lung abscess, peritonitis, renal infarcts, DIC, peripheral neuropathy
Vasculitis - 2° bacterial infection tissue necrosis gangrene skin loss