L11 12.PULMONARY TB

PULMONARY TB

1. PULMONARY

TUBERCULOSIS
DR.Bilal Natiq Nuaman,MD
CABM,FIBMS,DIM
2016-2017
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2. •Tuberculosis (TB) is caused by infection with
Mycobacterium tuberculosis (MTB)
Burden of TB
•TB is the seventh leading cause of death
worldwide
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3. • M. tuberculosis can cause disease in any
organ of the body.
•Multi-drug resistance (MDRTB) present in 102
of 109 countries surveyed from 1994-2003
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4. Mycobacterium tuberculosis are gram positive
aerobes and facultative intracellular
pathogens, usually infecting mononuclear
phagocytes.
Due to high lipid content in the cell wall, they
are relatively impermeable and stain only
weakly with Gram-stain. Where stained with
dye combined with phenol and washed with
acidic organic solvents, they resist
decolorization and therefore are termed
‘acid-fast bacilli’.
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6. Transmission
•M. tuberculosis is spread by the inhalation
of aerosolized droplet nuclei from other
infected patients. Once inhaled, the
organisms lodge in the alveoli and initiate
the recruitment of lymphocytes and
macrophages.
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7. Macrophages undergo transformation into
epithelioid and Langhans cells, which
aggregate with the lymphocytes to form the
classical tuberculous (caseating) granuloma

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9. Inhalation of M. tuberculosis and deposition in
the lungs leads to one of four possible
outcomes:
•Immediate clearance of the organism (no
disease)
•Latent infection
•Immediate onset of active disease (primary
disease)
•Onset of active disease many years
following exposure (reactivation disease)
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10. Definitions
●TB infection
●TB bacilli live inside the person, but the bacilli
do not cause pathological destruction of organs
●No signs or symptoms of disease
●TB disease
●TB bacilli progressively invade an organ(s)
●Signs and symptoms of disease appear
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11. ●Pulmonary TB
●Disease involves the lung parenchyma
●Smear-positive: visible TB bacilli in
sputum
●Smear-negative: no visible TB bacilli in
sputum
●Extra-pulmonary TB
●Disease involving an organ other than
the lung parenchyma
●Includes pleural TB
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12. Risk of Infection from Exposure
•Exposure to:
•Persons who cough
•Persons with sputum positive for acid-fast
bacilli
•Persons not on TB treatment
•Persons just started on TB treatment
•Persons with a poor response to TB treatment
•Close contact, for long amounts of time, outside
of natural sunlight (e.g., PRISON)
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14. Diagnosis of TB
Medical history
Physical examination
Investigations:
Bacteriologic or histologic exam
Mantoux tuberculin skin test
Chest radiograph
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15. MEDICAL HISTORY
•Symptoms of disease
•History of TB exposure, infection.
•Past TB treatment
•Risk factors and Medical conditions that
increase risk for TB disease.
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20. Sputum for AFB and culture
•Zeil Nielson acid stain, 60% sensitivity
• For diagnosis of pulmonary TB, obtain three
morning sputum specimens (sent for AFB
smear and mycobacterial culture)
•3 negative smears to assure low infectivity
(Does not exclude TB)
•Culture most sensitive and specific test. But
need more time 4-6 weeks
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21. 0.1 mL of 5-TU of purified protein derivative (PPD)
solution injected intradermally
Produce a wheal that is 6-10mm in diameter
Read within 48-72 hours
Measure induration, not erythema
Mantoux tuberculin skin test
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22. False negatives

•Severe TB (25% of cases negative)
•Newborn and elderly
•HIV (if CD4 count < 200 cells/ml)
•Recent infection (e.g. measles) or immunization
•Malnutrition
•Immunosuppressive drugs
•Sarcoidosis
False positives
•BCG vaccination
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23. Interferon-gamma release assays (IGRAs)

•They are whole-blood tests that can aid in diagnosing
Mycobacterium tuberculosis infection. IGRAs detect T-cell
secretion of interferon-gamma (IFN-γ) following exposure to
M tuberculosis-specific antigens (ESAT-6, CFP-10).
•They do not help differentiate latent tuberculosis infection
(LTBI) from tuberculosis disease.
•IGRAs will replace the tuberculin skin test in low incidence,
high-income countries.
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24. The advantages of IGRAs
•Requires a single patient visit to conduct the test.
•Results can be available within 24 hours.
•Prior BCG (bacille Calmette-Guérin) vaccination does not
cause a false-positive IGRA test result.
Disadvantages of IGRAs
•Higher costs
•Sophisticated equipment and need trained personnel.
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25. CXR Findings
•Primary TB:
•Lower or middle lobe infiltrates
•Reactivated TB:
•Apical infiltrates/ cavitations
•Latent TB:
•Usually normal
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27. High ESR(≥50)
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28. Clinical Forms of TB
•Primary
•Secondary or Reactivation
•Miliary
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34. Secondary Tuberculosis
•Reactivation occurs in 10-15% of patients;
1/2 within 2 years of primary disease
•The earliest radiological change is typically
an ill-defined opacity situated in one of the
upper lobes.
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PrImary Tuberculosis is a typical acute systemic disease of children.
secondary Tuberculosis is typically a chronic pulmonary disease of
adults and children older than 10. It is due to reactivation of dormant
bacilli due to a decrease in immunity or reinfection.The pulmonary
lesions are apical and bilateral in distribution arising from bacilli that
seeded to this site early in primary tuberculosis, which may have been
many years previously. Apical lesions tend to be well ventilated,
providing an environment rich in oxygen for the bacilli

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36. Secondary Tuberculosis
•Slowly Progressive (several months)
•Worsening cough with sputum production
•Low grade fever, night sweats, fatigue and
weight loss
•CXR : apical lordotic apical cavities (without
fluid),
•Cavitary disease very infectious.
• Isolate all patients.
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38. Miliary TB
•risk for disseminated tuberculosis
1)Teenagers exposed to TB for the first
time
2)Elderly patients with a past history of
TB exposure
3)HIV patients with a past history of TB
exposure.
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39. Miliary TB Clinical Manifestations
•Symptoms are nonspecific
•- Moderate grade fever

Night sweats, Malaise and anorexia

Weakness, Weight loss.
•Funduscopic exam - choroid tubercles
•Laboratory - leukemoid reaction, anemia

abnormal LFTs
•CXR - Micronodular interstitial pattern (millet
seeds)

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40. choroid tubercles
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42. •Diagnosis - blood cultures

bone marrow culture 

Liver biopsy
•Treatment - Early therapy for all
suspected cases 

(4 drugs)
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43. Extrapulmonary tuberculosis
Can occur in presence or absence of pulmonary TB
The most common sites of involvement, in descending
order, are
• pleura (with effusion),
•the lymph nodes (scrofula) ,
•skeletal system (T11 and T12 vertebrae are most often
affected) (pott disease),
•central nervous system,
•Urogenital system
•gastrointestinal tract, and
•Skin (lupus vulgaris)
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45. Patients are not considered infectious if they
meet all these criteria:
•Received adequate treatment for 2-3
weeks
•Favorable clinical response to treatment
•3 consecutive negative sputum smears
results from sputum collected on different
days
➢Extrapulmonary TB (including pleural
effusion),and latent TB patients are
not infectious
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Treatment of TB Disease

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48. Indications of corticosteroids in TB
Corticosteroids reduce inflammation and limit tissue
damage, and are currently recommended
when treating
1-pericardial or
2-meningeal disease,
3-children with endobronchial disease.
4-TB of the ureter,
5-pleural effusions ,
6-extensive pulmonary disease, and
7-can suppress hypersensitivity drug reactions.
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51. Latent TB Infection (LTBI) 

•Occurs when person breathes in bacteria and it
reaches the air sacs (alveoli) of lung Immune
system keeps bacilli contained and under control
Person is not infectious and has no symptoms
TB Disease
•Occurs when immune system cannot keep bacilli
contained Bacilli begin to multiply rapidly Person
develops TB symptoms
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54. THANK YOU
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