Trichosporon beigelii pneumonia in a patient with malignant histiocytosis.

A 30-year-old previously healthy housewife presented with bilateral pulmonary infiltrates. She was treated with various antibiotics but died with disseminated intravascular coagulation. Cultures of tracheal aspirates obtained prior to her death yielded Trichosporon beigelii. Postmortem examination revealed T. beigelii pneumonia with fungal dissemination in other organs. In addition, many organs were found to be infiltrated with atypical mononuclear cells which exhibited cytochemical properties of histiocytes. It was considered, therefore, that T. beigelii pneumonia developed on the basis of underlying malignant histiocytosis. T. beigelii in her lung sections was fluorescently stained with rabbit antiserum to the fungus isolated from the patient. This is the first report of Trichosporon beigelii pneumonia associated with malignant histiocytosis.