[Malignant histiocytosis. Clinical contribution and review of the subject]. / L'istiocitosi maligna. Contributo clinico e revisione dell'argomento.

Malignant histiocytosis (MH) is a rare and severe disease caused by malignant histiocyte degeneration in the sinuses of the reticuloendothelial system. The clinical picture presents fever, wasting, enlargement of the liver and spleen and lymphoadenopathy. Diagnosis is based on histological criteria and it may prove very difficult to differentiate between MH and malignant lymphomas, acute monocytic leukemia and the histiocytoses considered benign. The main features of the disease are described with comments on two personally experienced clinical cases. Emphasis is placed on the leukaemic aspect, the involvement of the CNS, the association, in one case, with sarcoidosis and the poor prognosis.