Familial hypercholesterolemia with unusual foamy histiocytes. Report of a case with myelophthisic anemia and xanthoma of the maxillary sinus

Accumulation of phagocytic histiocytes with a foam cell morphology has been described in a number of diseases. Familial hypercholesterolemia, one such disease, is characterized by foamy histiocytic accumulation in cutaneous or tendinous xanthomas and within atheromatous lesions. This report describes a patient with familial hypercholesterolemia who had two unusual manifestations of foamy histiocytic accumulation: a maxillary sinus xanthoma, which presented as an expansile mass, and diffuse bone marrow replacement with foamy histiocytes, which was associated with myelophthisic anemia. The accumulation of foamy cells in both locations resembled that seen in many of the storage diseases. The possibility of foamy histiocytic accumulation should be considered in the differential diagnosis of patients with these disease entities who present with space-occupying lesions.