Pathology: Caseatinggranulomatous disease
Inhalation of infection and alveolar macrophageengulfs bacterium.
Granuloma formation and enlargement of draining lymphnodes (Ghon complex)
Aetiology: Mycobacterium tuberculosis
Symptoms: Cough lasting > 3 weeksunresponsive to antibiotics, creamy white sputum, haemoptysis, upper lobe cavitation, fever, nightsweats, weight loss
Signs: Mild Disease: May have relatively fewsigns
Severe disease: Weightloss, lymphadenopathy, splenomegaly, erythema nodosum
Chest: Dullupper zones with crackles
Investigations: Chest X-Ray: Miliary shadowing, hilarlymphadenopathy, pleural effusion, cavitating
patchy consolidation in upper lobes, Ghon complex,signs of old TB
Mantoux (tuberculinskin test): Positive after 4-8 weeks on development of cellmediated immune response
Sputumculture: AcidFast Bacilli on Ziehl-Neelsen staining
Tissue forhistology: Caseating granulomas
Treatment: 6months anti-tuberculous chemotherapy in uncomplicated TB and contact tracing
Complications: Cavitation leadingto massive haemoptysis:
Rasmussen’s aneurysm (bronchial artery runs close tocavity and is eroded)
Drug side effects
Prognosis: Usuallygood with treatment
Figure 2.2 Left upperlobe cavitating consolidation on miliary TB background
