MYELOMATOSIS WITH XANTHOMATOSIS MULTIFORME.

A 45-year-old man developed, apparently simultaneously, two rare conditions, xanthomatosis (with hypercholesterolemia) and myelomatosis. His blood contained very high levels of cholesterol, the major part of which was present in a markedly elevated beta-lipoprotein fraction. Studies carried out over a period of six years, utilizing electrophoresis, ultracentrifugation, determinations of chemical composition and incorporation with C(14)-labelled glutamic acid and acetate, indicated a direct association between the two conditions, the myeloma lipoprotein apparently being produced by the abnormal plasma cells in the bone marrow. There were definite indications that the low density S(f) 0-12 lipoproteins were primarily involved.