BETA-2 LIPOPROTEIN MYELOMATOSIS.

Studies are reported on a patient who developed, apparently simultaneously, xanthomatosis (with hypercholesterolaemia) and myelomatosis. There was little biochemical change throughout his illness, about 6 years. The two conditions were shown to be related, namely the patient apparently had a very rare type of beta-2 lipoprotein myelomatosis. Evidence is presented suggesting that the abnormal beta-2 lipoprotein was synthesized in the abnormal plasma cells of the bone marrow. There were also definite indications that the low-density Sf 0–12 lipoproteins were primarily involved, and the Sf 20–400 serum lipoproteins increased because of the great demand for cholesterol by the bone marrow. Curiously, there was normal erythropoiesis in the bone marrow with resulting normal blood haemoglobin levels. The principal clinical problem was the continued loss of minerals from bone with progressive osteoporosis.