Cavitary TB is caused by which process?

Cavitary TB is caused by which process?

• A. Liquefaction and expulsion of necrotic, caseous material forming a cavity
• B. Granuloma containment of bacteria
• C. Immediate airway obstruction without tissue destruction
• D. Cavitation due to viral co-infection

Answer: (A)

Cavitary disease in pulmonary TB happens when a granuloma with caseous necrosis undergoes liquefaction and drains into the airways, leaving a hollow space in the lung. The immune response to TB forms granulomas with macrophages that turn into epithelioid cells and Langhans giant cells, producing a center of caseous necrosis. Over time, enzymes and breakdown of necrotic tissue liquefy this area, and the liquefied material erodes into bronchi, creating a cavity. This cavity harbors a high burden of bacilli and facilitates transmission. This differs from mere containment within a granuloma, which would not produce cavitation, and it isn’t driven by immediate airway obstruction or by viral co-infection.

Cavitary disease in pulmonary TB happens when a granuloma with caseous necrosis undergoes liquefaction and drains into the airways, leaving a hollow space in the lung. The immune response to TB forms granulomas with macrophages that turn into epithelioid cells and Langhans giant cells, producing a center of caseous necrosis. Over time, enzymes and breakdown of necrotic tissue liquefy this area, and the liquefied material erodes into bronchi, creating a cavity. This cavity harbors a high burden of bacilli and facilitates transmission. This differs from mere containment within a granuloma, which would not produce cavitation, and it isn’t driven by immediate airway obstruction or by viral co-infection.