Sensitivity of fine‐needle aspiration biopsy in the detection of mycobacterial infections

A series of 290 fine needle aspiration biopsies (FNABs) processed for mycobacterial cultures are reviewed. The clinicopathologic features in 162 cases were suggestive of tuberculous infection and 86 (53%) of the samples in these cases were culture positive. A comparative histologic and cytologic correlation was carried out in 23 cases. Aspiration smears from caseating granulomas were composed of necrotic debris containing large numbers of polymorphonuclear cells and scattered histiocytes, epithelioid cells, and multinucleated giant cells. In cases of noncaseating granulomas, the smears revealed well-defined aggregates of epithelioid cells without necrotic debris or significant numbers of other inflammatory cells. There was a close correlation between the histologic and cytologic diagnosis of caseating and/or noncaseating granulomatous inflammation.