Cutaneous involvement in malignant histiocytosis. Case report and review of the literature.

Malignant histiocytosis (MH) is a rare, malignant neoplasm with protein manifestations, including fever, lymphadenopathy, hepatosplenomegaly, pancytopenia, and, infrequently, cutaneous lesions. A patient had initial manifestations that included fever and skin lesions. Skin lesions began on distal areas of the extremities and spread to involve proximal areas of the extremities and the abdomen. Erythematous maculopapular lesions, nodules, and plaques were present in various stages of development, which evolved into ulcerated plaques that exuded a serosanguineous discharge. Spontaneous healing of lesions occurred, leaving hyperpigmented, atrophic scars. Histologically, the deep dermis and subcutaneous tissues contained a diffuse infiltrate of histiocytes, lymphocytes, and mononuclear cells. Erythrophagocytosis by histiocytes was present in the skin biopsy material. Thirteen percent of 320 cases in the literature had skin involvement. This report and review of the literature indicate that, in selected cases, skin biopsy may contribute to the diagnosis of MH.