(an ancient persistent continuing human companion) dr. awadh al-anazi
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TUBERCULOSISTUBERCULOSIS
(An ancient persistent (An ancient persistent continuing human continuing human
companion)companion)
Dr. Awadh Al-AnaziDr. Awadh Al-Anazi
WHAT IS IT?WHAT IS IT?
Bacterial infectionBacterial infection Caused by Caused by Mycobacterium Mycobacterium tuberculosis tuberculosis (also called (also called tubercle bacillustubercle bacillus)) Damages a person’s lungs or Damages a person’s lungs or
other parts of the body other parts of the body Fatal if not treated properlyFatal if not treated properly
SYMPTOMSSYMPTOMS Perpetual CoughPerpetual Cough FeverFever Weight lossWeight loss Night sweatsNight sweats Loss of appetiteLoss of appetite FatigueFatigue Swollen glands (lymph nodes)Swollen glands (lymph nodes) ChillsChills Pain while breathingPain while breathing
MICROBIOLOGYMICROBIOLOGY
Organism: Organism: – Mycobacterium tuberculosisMycobacterium tuberculosis– AerobicAerobic– Non-spore forming ,non-motileNon-spore forming ,non-motile– Rod..: 2—5 mm longRod..: 2—5 mm long– Resistant to disinfectantResistant to disinfectant– Once stained it resists decolorization with Once stained it resists decolorization with
acid and alcohol facultative intracellular acid and alcohol facultative intracellular organismorganism
Human is the main reservoir of M TBHuman is the main reservoir of M TB
EPIDEMIOLOGYEPIDEMIOLOGY
It is a world wide diseaseIt is a world wide disease Tb infects 1.7 billion with 3 million Tb infects 1.7 billion with 3 million
deaths/yrdeaths/yr UK: 1st half of 20UK: 1st half of 20thth century: a lot of century: a lot of
death secondary to TB epidemicdeath secondary to TB epidemic 90% of cases and 95% of death 90% of cases and 95% of death
occurred in developing countries.occurred in developing countries. No of cases in developed countries No of cases in developed countries
has declined because of: has declined because of:
EPIDEMIOLOGYEPIDEMIOLOGY
Case finding and chemotherapyCase finding and chemotherapy Tuberculous infection: a state in Tuberculous infection: a state in
which the tubercle bacillus is which the tubercle bacillus is established in the body without established in the body without symptoms.symptoms.
Tuberculous disease: a state in which Tuberculous disease: a state in which one or more organs of the body one or more organs of the body becomes diseased by the disease.becomes diseased by the disease.
Improved nutritionImproved nutrition
EPIDEMIOLOGYEPIDEMIOLOGY
What increases the spread of the What increases the spread of the disease: disease: 1) crowding living 1) crowding living 2) migration of people from 2) migration of people from
endemic endemic area.area. 10% of infected people ---- active 10% of infected people ---- active
diseasedisease 50%of active disease --- 50%of active disease ---
contagiouscontagious
EPIDEMIOLOGYEPIDEMIOLOGY
What increases the risk of What increases the risk of developing disease after TB developing disease after TB infection ?infection ?– Infecting doseInfecting dose– Host factorsHost factors
age: under 5 yrs age: under 5 yrs debilitating illness and poor nutritiondebilitating illness and poor nutrition alcoholismalcoholism gastrectomygastrectomy diabetes mellitusdiabetes mellitus
MODE OF SPREAD & MODE OF SPREAD & TRANSMISSIONTRANSMISSION Inhalation of droplet nucleiInhalation of droplet nuclei Spreads through the air when Spreads through the air when
a person with active TB: a person with active TB: Coughs/ Speaks/ Laughs/ Sneezes/ Coughs/ Speaks/ Laughs/ Sneezes/
SingsSings Another person breathes in the Another person breathes in the
bacteria and becomes infectedbacteria and becomes infected
INSIDE THE BODYINSIDE THE BODY
Breathe in infected air and bacilli go to lungs Breathe in infected air and bacilli go to lungs through bronchiolesthrough bronchioles
Bacilli infect alveoliBacilli infect alveoli Macrophages attack bacteria, but some Macrophages attack bacteria, but some
survivesurvive Infected macrophages separate and form Infected macrophages separate and form
tuberclestubercles Dead cells form granulomasDead cells form granulomas
INSIDE THE BODY (cont.)INSIDE THE BODY (cont.)
As a person breathes in infected air, the bacilli go the lungs through As a person breathes in infected air, the bacilli go the lungs through the bronchioles. At the end of the bronchioles are alveoli, which are the bronchioles. At the end of the bronchioles are alveoli, which are balloon-like sacs where blood takes oxygen from inhaled air and balloon-like sacs where blood takes oxygen from inhaled air and releases carbon dioxide into the air exhaled. releases carbon dioxide into the air exhaled.
TB bacilli infect the alveoli and the bodyπs immune system begins to TB bacilli infect the alveoli and the bodyπs immune system begins to fight them. Macrophages — specialized white blood cells that ingest fight them. Macrophages — specialized white blood cells that ingest harmful organisms — begin to surround and "wall off" the harmful organisms — begin to surround and "wall off" the tuberculosis bacteria in the lungs, much like a scab forming over a tuberculosis bacteria in the lungs, much like a scab forming over a wound. wound.
Then, special immune system cells surround and separate the Then, special immune system cells surround and separate the infected macrophages. The mass resulting from the separated infected macrophages. The mass resulting from the separated infected macrophages are hard, grayish nodules called tubercles.infected macrophages are hard, grayish nodules called tubercles.
INSIDE THE BODY (cont.)INSIDE THE BODY (cont.)
Active TB spreads through the lymphatic system to Active TB spreads through the lymphatic system to other parts of the body. In these other parts, the other parts of the body. In these other parts, the immune system kills bacilli, but immune cells and local immune system kills bacilli, but immune cells and local tissue die as well. The dead cells form masses called tissue die as well. The dead cells form masses called granulomas, where bacilli survive but don’t grow. granulomas, where bacilli survive but don’t grow.
As more lung tissue is destroyed and granulomas As more lung tissue is destroyed and granulomas expand, cavities develop in the lungs, which causes expand, cavities develop in the lungs, which causes more coughing and shortness of breathe. Granulomas more coughing and shortness of breathe. Granulomas can also eat away at blood vessels which causes can also eat away at blood vessels which causes bleeding in the lungs, and bloody sputum.bleeding in the lungs, and bloody sputum.
PATHOGENESISPATHOGENESIS
Droplet nuclie ---terminal air Droplet nuclie ---terminal air space ---space ---
Multiplication … initial focusMultiplication … initial focus– SubpleuralSubpleural– 75%single75%single
Migration through blood and Migration through blood and lymph node --- another focuslymph node --- another focus
Ingestion of the bacteria by the Ingestion of the bacteria by the macrophage --- slow multiplicationmacrophage --- slow multiplication
IMMUNOLOGICAL FEATUREIMMUNOLOGICAL FEATURE
TB require CMI for its controlTB require CMI for its control Ab response is rich but has no role Ab response is rich but has no role Multiplication proceeds for weeks Multiplication proceeds for weeks
both in:both in:– initial focusinitial focus– lymphohaematogenous metastatic focilymphohaematogenous metastatic foci
Until development of ... cell Until development of ... cell mediated immunitymediated immunity
CLINICAL FEATURESCLINICAL FEATURESACTIVE vs. LATENT INFECTIONACTIVE vs. LATENT INFECTION Unhealthy personUnhealthy person
Bacilli overwhelm immune systemBacilli overwhelm immune system Bacilli break out of tubercles in alveoli and Bacilli break out of tubercles in alveoli and
spread through bloodstream spread through bloodstream This is (active) TBThis is (active) TB Healthy personHealthy person Initial infection controlled by immune systemInitial infection controlled by immune system Bacilli remain confined in tubercles for yearsBacilli remain confined in tubercles for years This is(latent) TBThis is(latent) TB
MOST SUSCEPTIBLEMOST SUSCEPTIBLE
People at higher risk of TB infection People at higher risk of TB infection Close contacts with people with infectious TBClose contacts with people with infectious TB People born in areas where TB is commonPeople born in areas where TB is common People with poor access to health carePeople with poor access to health care People who inject illicit drugsPeople who inject illicit drugs People who live or work in residential facilitiesPeople who live or work in residential facilities Health care professionalsHealth care professionals The elderlyThe elderly
MOST SUSCEPTIBLE (CONT.)MOST SUSCEPTIBLE (CONT.)
People at higher risk of active TB diseasePeople at higher risk of active TB disease People with weak immune systems People with weak immune systems
(especially those with HIV or AIDS) (especially those with HIV or AIDS) People with diabetes or silicosisPeople with diabetes or silicosis People infected within the last 2 yearsPeople infected within the last 2 years People with chest x-rays that show previous TB People with chest x-rays that show previous TB
diseasedisease Illicit drug and alcohol abusersIllicit drug and alcohol abusers
CLINICAL FEATURESCLINICAL FEATURES
Pulmonary 80%Pulmonary 80% Extra pulmonary 20%Extra pulmonary 20% Pulmonary tuberculosisPulmonary tuberculosis Primary: the lung is the 1Primary: the lung is the 1stst organ organ
involved ... middle and lower lobe.involved ... middle and lower lobe. Health: asymptomatic Health: asymptomatic Heals spontaneouslyHeals spontaneously CXR normal.CXR normal.
CLINICAL FEATURESCLINICAL FEATURES
MalnutritionMalnutrition HIVHIV Severe casesSevere cases
– primary lesion progress to clinical primary lesion progress to clinical illnessillness
– cavitating pneumoniacavitating pneumonia– lymphatic spread and lobar collapse lymphatic spread and lobar collapse
due to LNdue to LN 40% haematogenous dissemination 40% haematogenous dissemination
CLINICAL FEATURESCLINICAL FEATURES
In children In children Asymptomatic state may cause Asymptomatic state may cause
miliary tuberculosis and TB miliary tuberculosis and TB meningitis meningitis
Clinical featuresClinical features
Post primary (reactivation)Post primary (reactivation) Result from endogenous Result from endogenous
reactivation of latent infection reactivation of latent infection and manifest clinically : and manifest clinically : – fever and night sweatfever and night sweat– weight lossweight loss– cough… non-productive then cough… non-productive then
productiveproductive And may have haemoptysisAnd may have haemoptysis Signs: rales in chest examSigns: rales in chest exam
C .F cont.C .F cont.
Extra pulmonary Extra pulmonary – lymph node lymph node – pleural pleural – bone and jointbone and joint– meningesmeninges– peritoniumperitonium
C F.CONTC F.CONT
Tuberculous lymphadenitis … 25 %Tuberculous lymphadenitis … 25 % The commonestThe commonest Localized painless swellingLocalized painless swelling Common sites: cervical & Common sites: cervical &
supraclavicularsupraclavicular Early: glands are discreteEarly: glands are discrete Late: glands are matted -/+ sinusLate: glands are matted -/+ sinus Dx: FNA 30% in biopsy for histo Dx: FNA 30% in biopsy for histo
and cultureand culture
C.F contC.F cont Pleural TbPleural Tb Result form penetration by few Result form penetration by few
bacilli into the pleural space bacilli into the pleural space resulting into :resulting into :– pleural effusion and fever pleural effusion and fever – DX; aspirate --- exudate DX; aspirate --- exudate – AFB rarely seen AFB rarely seen – culture 30% positiveculture 30% positive– BX 80% granulomaBX 80% granuloma
C.F. contC.F. cont
Skeletal Tb Skeletal Tb Source: Source:
– reactivation of haematogenous focusreactivation of haematogenous focus– spread from an adjacent LN spread from an adjacent LN
Common sites: spine --- hips --- Common sites: spine --- hips --- kneesknees
Spinal Tb:Spinal Tb: Dorsal site is the commonest site Dorsal site is the commonest site
C.F.contC.F.cont
Involve two vertebral bodies and Involve two vertebral bodies and destroy the disc in between.destroy the disc in between.
Advance disease Advance disease Collapse fracture of the bodies ------Collapse fracture of the bodies ------ Kyphosis and gibbus deformityKyphosis and gibbus deformity Paravertebral abscess(cold abcess)Paravertebral abscess(cold abcess) Dx: ct scan and MRIDx: ct scan and MRI Biopsy: histopathBiopsy: histopath
C.F.contC.F.cont
Tuberculous meningitis Tuberculous meningitis Most often: children and may affect Most often: children and may affect
adultadult
Source: Source: – blood spread blood spread – rupture of a sub-ependymal tuberclerupture of a sub-ependymal tubercle
C.F.contC.F.cont
Symptoms: Symptoms: – fever fever – headache headache – neck rigidity neck rigidity
Disease typically evolve in 2 wks. Disease typically evolve in 2 wks. Dx; csf Dx; csf
TB AND AIDSTB AND AIDS
Person with active TB are more Person with active TB are more frequent to have HIV than general frequent to have HIV than general populationpopulation
AIDS in HAITIANS: almost all children AIDS in HAITIANS: almost all children are positive for PPD --- active TB in are positive for PPD --- active TB in 60%60%
New York: 50% of active TB patients New York: 50% of active TB patients are HIV+are HIV+
Tb&AidsTb&Aids
Africans: 60% of active TB Africans: 60% of active TB patients are HIV+patients are HIV+
TB can appear at any stage of HIV TB can appear at any stage of HIV infectioninfection
But presentation varies with the But presentation varies with the stage: stage:
Tb&AidsTb&Aids
Early:Early:– Typical pattern of upper lobe infiltrate -Typical pattern of upper lobe infiltrate -
+cavitation …+cavitation … Late: Late:
– diffuse infiltrate .. no cavitation .. LNdiffuse infiltrate .. no cavitation .. LN Sputum is less frequent to be + for AFB Sputum is less frequent to be + for AFB
with HIV than without.with HIV than without. Extra pulmonary is more common … Extra pulmonary is more common …
40%40%
Tb&AidsTb&Aids
Pulmonary TB and HIV --- Pulmonary TB and HIV --- diagnosis is difficultdiagnosis is difficult– sputum (-) in 40 %sputum (-) in 40 %– atypical CXRatypical CXR– negative PPDnegative PPD
DIAGNOSISDIAGNOSIS
For any respiratory symptoms:For any respiratory symptoms: Do chest x-ray … if abnormal ---Do chest x-ray … if abnormal ---
– Sputum for :Sputum for : Zn stain Zn stain culture ..definite diagnosisculture ..definite diagnosis
– Use lowenstein-jansen mediaUse lowenstein-jansen media slow growth … 3 - 6 wksslow growth … 3 - 6 wks Bactic liquid media ...Bactic liquid media ...
DIAGNOSISDIAGNOSIS
PPD … intradermally …PPD … intradermally … 5 unit in o.1 ml 5 unit in o.1 ml 10 mm: 90 % infected10 mm: 90 % infected More than 15 mm: 100% infectedMore than 15 mm: 100% infected BCG and positive PPD:BCG and positive PPD: Unless very recent: positive PPD Unless very recent: positive PPD
of more than 10mm should not be of more than 10mm should not be due to BCGdue to BCG
DIAGNOSISDIAGNOSIS
Skin test- Mantoux testSkin test- Mantoux test
PPD injected in forearm PPD injected in forearm and examined 2-3 days and examined 2-3 days later later
Red welt around injection Red welt around injection indicates infection indicates infection
Examine medical history, Examine medical history, x-rays, and sputum x-rays, and sputum
DIAGNOSISDIAGNOSIS
False negative resultFalse negative result 20 % of active disease20 % of active disease MalnutritionMalnutrition SarcoidSarcoid Viral infectionViral infection SteroidSteroid PPD: is of limited value because PPD: is of limited value because
of of Low sensitivity and specificityLow sensitivity and specificity
TREATMENTTREATMENT
Chemotherapy: cure Chemotherapy: cure Isonised Isonised RifampicinRifampicin PyrazinamidePyrazinamide Ethambutol/streotomycinEthambutol/streotomycin
– rapidly reduce the number of viable rapidly reduce the number of viable organismorganism
– kill the bacillikill the bacilli– slow rate of induction of drug resistanceslow rate of induction of drug resistance
Treatment contTreatment cont
Drug failureDrug failure– none compliancenone compliance– in appropriate drugin appropriate drug– drug resistance drug resistance
INFECTION CONTROLINFECTION CONTROL Active pulmonary tuberculosis:Active pulmonary tuberculosis:
– Isolation of the patient Isolation of the patient – Isolation room should be negative Isolation room should be negative
pressurepressure– Patient remain until 3 negative Patient remain until 3 negative
smears and there is clinical smears and there is clinical improvementimprovement
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