Biochemical abnormalities in multiple myeloma.

Monoclonal gammopathies can either be benign or more commonly malignant. The commonest disease associated with it is multiple myeloma. Over the seven-year period 1984-1990, two hundred and thirty-four monoclonal gammopathies were seen at the University Hospital, Jamaica. Multiple myeloma was diagnosed in one hundred and fifty-six cases (84 males and 72 females). The diagnoses of most of the others were not known as the samples came from other institutions. Of the patients with myeloma, the most common immunoglobulin type was IgG followed by IgA and then pure light chain disease. Only in about half of the cases where urine was analysed was Bence-Jones protein found. The majority of the cases had abnormal total serum protein, albumin and total globulin concentrations. Most of the cases also were in renal failure. Hypercalcaemia, hyperphosphataemia, elevated alkaline phosphatase, gammaglutamyl transferase and aspartate aminotransferase occurred in about one-third of them. These results were not much different from those reported in other countries.