Abstract
A 17 years old male who had been receiving growth hormone treatment for pituitary dwarfism for 20 months developed malignant histiocytosis (MH). He had had a history of severe hypersensitivity to mosquito bites since the age of 4. Before and upon admission he had 5 episodes of high fever which occurred cyclically about 4 weeks apart. The febrile phase was associated with hepatosplenomegaly, pancytopenia, marked elevation of serum LDH activity and ferritin level, all of which almost subsided or became normal during the afebrile phase. Accordingly, it was difficult to diagnose him as having MH. During the fifth episode of fever, hepatosplenomegaly increased markedly, atypical, immature monocytoid cells appeared in the bone marrow, and serum ferritin and LDH activity were extraordinarily elevated, strongly suggesting a diagnosis of MH. Combination chemotherapy resulted in a marked decrease in hepatosplenomegaly. However, MH was complicated with cerebral hemorrhage, and he died 3 months after admission. Immunohistochemical results showing positivity for lysozyme and α1 antichymotrypsin and negativity for pan T antigen confirmed the diagnosis of MH. Of several serum cytokines assayed, M-CSF and IFN γ showed increase during the febrile phase and normalization during the afebrile phase.
