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Pathology
Caseating granulomatous disease
Inhalation of infection and alveolar macrophage engulfs bacterium.
Granuloma formation and enlargement of draining lymph nodes (Ghon complex)
Aetiology
Mycobacterium tuberculosis
Signs
Mild Disease: May have relatively few signs
Severe disease: Weight loss, lymphadenopathy, splenomegaly, erythema nodosum
Chest: Dull upper zones with crackles.Symptoms
Cough lasting > 3 weeks unresponsive to antibiotics, creamy white sputum, haemoptysis, upper lobe cavitation, fever, night sweats, weight loss
Investigations
Chest X-Ray: Miliary shadowing, hilar lymphadenopathy, pleural effusion, cavitating
patchy consolidation in upper lobes, Ghon complex, signs of old TB
Mantoux (tuberculin skin test): Positive after 4-8 weeks on development of cell mediated immune response
Sputum culture: Acid Fast Bacilli on Ziehl-Neelsen staining
Tissue for histology: Caseating granulomas
Treatment
6 months anti-tuberculous chemotherapy in uncomplicated TB and contact tracing
Prognosis
Usually good with treatment
Cavitation leading to massive haemoptysis:
Rasmussen’s aneurysm (bronchial artery runs close to cavity and is eroded)
Drug side effects
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