Fine needle aspiration cytology of granulomatous diseases of the lung, including nontuberculous Mycobacterium infection.

The spectrum of cytomorphologic changes of pulmonary granulomas diagnosed by fine needle aspiration (FNA) biopsy is reported, with a review of the pertinent literature concerning the cytologic diagnosis of granulomatous disease. In our cases, organisms were not seen in the Papanicolaou-stained smears. Recognition of the granulomatous cellular pattern, however, resulted in a thorough search for organisms by special stains, and an etiologic diagnosis was made in each case. These cases emphasize the need for routine staining and culture of FNA material when an initial diagnosis of malignancy is not made. One of the cases appears to be the first report of a nontuberculous Mycobacterium infection diagnosed by fine needle aspiration biopsy.