Tuberculosis is caused by Mycobacterium tuberculosis and commonly affects the lungs. It spreads through airborne particles from the sputum of infected individuals. Latent TB occurs when a person is infected but not infectious, while active TB can spread. Symptoms include cough, weight loss, fever and night sweats. Risk factors that increase the chance of developing active TB include HIV, malnutrition, smoking and diabetes. Treatment requires a multi-drug regimen for 6-12 months to prevent resistance, with sputum cultures used to monitor response.

1. TUBERCULOSIS
DR NZOOLO
DEPT MEDICINE

2. Tuberculosis
-clinical disease caused by mycobacterium
tuberculosis(tubercle bacilli)
-delayed type iv hypersensintivity reaction
-may occur without symptoms
-transmission—aerosol particles
-source –sputum positive pts
- lungs most common site-85% of pts with
TB present with pulmonary complaints

3. PATHOGENESIS
-typical TB lesion is an epithelioid
granuloma
with central caseation necrosis
-most common site of primary lesion is
within alveolar macrophages and sub pleural
regions of the lung.
-Bacilli proliferate locally and spread thru the
lymphatics to a hilar node forming the ghon
complex

4. PATHOPHYSIOLOGY
-infection results most commonly thru exposure of
the lungs or mucous membranes to infected
aerosol.
-a single cough can generate 3000 infective
droplets with as few as 10 bacilli needed to initiate
infection.
-inhaled droplet nuclei are deposited within
terminal airspaces of the lung.
-the pathogens grow in numbers(1000-10000) for
2-12 weeks such that they elicit a cellular immune
response

5. when infected, you can have
1.LATENT TB-host contains TB-CAN NOT
SPREAD
2.ACTIVE TB. Can spread
CLINICAL FEATURES.
.cough
.weight loss/anorexia
.fever
.night sweats
.hemoptysis
.chest pain
.fatigue

6. Risk of acquiring active TB increases with
-HIV infection
-IV drug abuse
-malnutrition
-alcoholism
-DM
-Immunosuppressive therapy
-malignancies
-End stage renal disease
-extremities of age
-smoking
-chronic malabsorption syndromes
-pneumoconiosis

7. Reactivation Tuberculosis
-seen in adults
-dormant bacilli become activated
-usually posterior portions of upper lobe

8. -systemic and local symptoms
-low grade fever, night sweats,
fatigue,anorexia,and malaise
-local-cough,pleuritic chest pain and
hemoptysis
-chronicity and cavitation common.LN
involvement minimal
-signs include crepitations.
-chest x-ray infiltrates or cavitations
-definitive diagnosis-microbiological-ZN stain
or sputum cultures

9. Tubercular pleurisy with effusion
-acute or insidious onset
-fever, pleuritic chest pain,and breathlesness
-pleural friction rub and evidence of a pleural
effsion on physical examination
-straw coloured fluid on thoracentesis
-exudate with increased lymphocytes
-increased ADA.

10. Extra pulmonary Tuberculosis
1.miliary tuberculosis
-hematogenous dissemination
-widespread pathological presence
-increased in infancy,elderly,HIV ETC
-fever important feature(+ anorexia, weight
loss etc.)
-nonspecific pulmonary symptoms
-headache---meningeal involvement
-fever of undetermined origin
-DIC,anemia,no localizing signs and normal cxr
-tests-cxr(pulmonary findings in 50%),LN,and
spleen(15%),pancytopenia ,raised liver enzymes,

11. fatal if no treatment
-poor prognosis---infancy,elderly,HIV.
Others
1.CNS (TBM)
2.osteoarticular TB
3.TB lymphadenitis
4.abdomininal TB
5.TB pericarditis
6.TB with endocrine dysfunction

12. Anti TB chemotherapy
two requirements
1.multiple drugs-prevent resistance
2.prolonged period-bacilli lie dormant and
multiply slowly
-6 to 12 months of Rx
two phases
1.intensive phase-4 drugs (2mons)- 4FDC
2.continuation phase-2drug(4/10 months)-R
and I

13. -SPUTUM CULTURE gold standard
-symptomatic improvement evident in 2-3 wks
-smear examinations at monthly intervals desirable
-generally sputum negative after 2 mons of RX
-If sputum negative after 2 mons of RX repeat the
smears after completion of therapy.
-if treatment failure, change drugs in combination
rather than singly.
-non-responders may have MDR TB
-CXR also may be used as a tool to monitor
response
-if no improvement of CXR after 3 mons then RX
failure

14. First line drugs
1.isoniazide
-bactericidal
-only active against dividing bacteria
-inhibits mycolic acid and DNA synthesis
-excellent tissue penetrator
-peripheral neuropathy-use B6(Pyridoxine)
2.Rifampicin
-broad spectrum antibiotic
-bactericidal
-inhibits RNA synthesis
-excellent tissue penetration
-red discoloration of bodily fluids and renal
dysfunction

15. 3.Pyrazinamide
-bacteriostatic
-excellent tissue penetration
-interferes with FAS
-Liver toxicity
4.Ethambutol
-bacteriostatic
-interferes with cell wall synthesis
-good tissue penetration
-visual acuity

16. Second line drugs
-used in MDR TB-
capreomycin,kanamycin,amikacin,cycloserin
e,
ethionamide,ciprofloxacin,ofloxacin,aminosal
icylic acid
adjunct therapy (PTB)
-surgical-persistent
empyema,bronchopleural fistula,resection of
large cavities
-steroids-ARDS,pericarditis,adrenal
insufficiency.

17. 3Is in TB Mgt
 1.isoniazide preventive therapy
 2.intensified case finding
 3.infection prevention and control