Plasma cholesterol concentration and extra lipid band in monoclonal gammopathies.

Plasma lipids and lipoproteins were studied in 21 patients with benign monoclonal gammopathy, 21 patients with multiple myeloma and seven patients with Waldenström's macroglobulinaemia. Results were compared with those of a control group, age and sex matched. Low plasma cholesterol levels in all three patient groups were associated with low HDL-cholesterol concentrations. Apo A-I, but not apo B, was significantly reduced. Sixty per cent of the patients exhibited an extra lipid band on plasma lipoprotein electrophoresis, which could be an immunoglobulin-lipid complex. In these patients plasma and LDL-cholesterol levels were significantly lower than in those patients in whom this band was absent. No correlation was found between the severity of the disease and plasma lipid pattern.