Autopsy findings in hairy cell leukemia

Autopsy material from 22 patients with hairy cell leukemia was examined. All patients had the expected widespread involvement of the hematopoietic system. Peripheral lymphadenopathy was detected in only three cases, but significantly enlarged mediastinal, retroperitoneal, and abdominal lymph nodes were present in 15. Lymph nodes of two patients showed malignant lymphoma, large-cell type. Evidence of pulmonary infiltration by hairy cells was present in 15 cases; but in 14 of the 15, there was evidence of coexisting pneumonia, and in 13 of the 15 cases the presence of microorganisms was documented. Only one patient demonstrated clinical findings attributable solely to lung involvement by hairy cell leukemia. Liver involvement was present in every case, but the extent of the leukemic infiltration did not always correlate with serum biochemical abnormalities, and there was no correlation with the hairy cell count in the peripheral blood. M kansasii was found in the lymph nodes of three patients and in the lung and liver specimens of one of these. The tissue response in two of the patients with M kansasii consisted of the presence of poorly formed granuloma; the third patient had only focal areas of necrosis, with no polymorphonuclear or macrophage response.