Tuberculosis granulomas are characterized by which type of necrosis?

• A. Liquefactive necrosis
• B. Caseous necrosis
• C. Fat necrosis
• D. Coagulative necrosis

Answer: (B)

In tuberculosis, the granulomas form a central area of caseous necrosis. This cheese-like, amorphous, eosinophilic material results from the death of macrophages within the granuloma as the cell-mediated immune response attempts to contain the infection. Surrounding this necrotic center are activated macrophages (epithelioid cells) and Langhans-type giant cells, all encased by lymphocytes, creating the characteristic structure.

This pattern is distinct from other types of necrosis. Liquefactive necrosis involves tissue digestion that creates liquid-filled spaces and is typical of brain infarcts. Fat necrosis arises from enzymatic destruction of fat, as seen with pancreatitis. Coagulative necrosis preserves tissue architecture and occurs in solid organ infarcts, but the TB granuloma center loses structure in a caseous way rather than maintaining a solid outline.

So the necrosis described in tuberculosis granulomas is caseous necrosis.