Normolipemic subcutaneous xanthomatosis.

A patient with diabetes mellitus is described in whom an unusual xanthomatosis developed involving large areas of the subcutaneous tissue and vocal cords. Few lesions were present on the skin. Plasma lipid, lipoprotein, apolipoprotein, and cholestanol levels revealed normal patterns. Electron microscopy showed macrophages with vacuolar and crystal lipid inclusions. Results of lipid and enzyme analysis of the subcutaneous xanthoma were similar to those of xanthomas derived from a patient with diabetes mellitus and type V hyperlipidemia. The mechanism of this xanthomatosis remains unknown.