The formation of pulmonary mycetomata.

Pulmonary mycetomata appeared in the previously normal lung of a patient being treated for acute leukemia. The roentgenographic progression from normal lung through poorly defined infiltrates to well developed mycetomata was quite rapid, about two weeks, and coincided with recovery from prolonged leukopenia. The mycetomata were removed soon after their formation and microscopic study revealed that the lesions were autoamputated spheres of lung tissue containing hyphae. This is the first report demonstrating that mycetomata may be primarily "lung balls" rather than "fungus balls." Cleavage of infected from adjacent healthy lung tissue is apparently accomplished through leukocyte enzymatic activity. The appearance of mycetomata in a preexisting pneumonic infiltrate may herald improved host resistance with conversion of a deeply infiltrating process to relatively extrinsic surface colonization and specific treatment may be unwarranted.