[Pathology of the phagocytic mononuclear system. Apropos of 4 cases]

Four patients, with disorders belonging to mononuclear phagocyte system diseases are described: a case of malignant histiocytosis; one of Weber-Christians disease and two siblings affected by familiar erythrophagocytic lymphohistiocytosis. An attempt is made to update classification of this group of diseases previously known as reticulosis, reticulohistiocytosis, reticuloendotheliosis, etcetera.