Multicentric reticulohistiocytosis, another lipid disorder with normolipidemic xanthomatosis?

This report describes a 72-year-old female patient with 2 types of severely disfiguring xanthomas, particularly on the facial area and the upper arms. Biopsy revealed xanthoma-type cells, histiocytes, and multiple giant cells. The soft yellowish facial xanthomata were rich in esterified cholesterol, whereas the cholesterol content of the colorless, firm, fibrous xanthoma of the arms was relatively low. The clinical course of insidiously starting polyarthritis, the formation of skin and tendon xanthomas (at the age of 63) and, finally, the histological findings verified the diagnosis of multicentric reticulohistiocytosis. The family history and findings were noncontributory. The patient had symptoms of moderate coronary heart disease and died from an acute myocardial infarction. Her total cholesterol and triglyceride levels were 182 and 89 mg/dl, and the HDL cholesterol value was 43 mg/dl. Plasma levels of apolipoprotein A-I, A-II and B were normal, and her apoprotein E pattern was E3/E3. The triglyceride/cholesterol ratio of VLDL, the concentration of apo-LDL (LDL protein) and the LDL-protein/cholesterol ratio were normal. The apo-LDL production, the total clearance rate of apo-LDL, and the receptor-mediated and receptor-independent catabolism of LDL were also normal. Fecal output of neutral sterols and bile acids and the total body cholesterol synthesis were normal, but cholesterol absorption tended to be increased. The response to cholestyramine treatment showed a 44% decrease in the serum cholesterol level and a normal 5-fold increase in cholesterol synthesis. The patient's xanthoma formation could not be associated with any of the causes known to promote the development of normolipidemic xanthomatosis. It is suggested that multicentric reticulohistiocytosis should be considered in the differential diagnosis of patients with normolipidemic xanthomatosis.