Study of dyselectrolytemia in patients with multiple myeloma

Multiple myeloma (MM) is a malignant disease of plasma cells characterized by proliferation of a specific myelomatous clone of cells. It is second most common hematologic cancer. Renal impairment is observed in nearly half of the patients with multiple myeloma and 20% progress to renal failure due to precipitation of excess proteins in tubuli. Hyperproteinemia is associated with low plasma water levels causing unrealistically low electrolyte levels. Hyponatremia is one of the most commonly observed electrolyte disturbance. Evaluation of dyselectrolytemia in these patients and association with renal disease is useful in management and helps in monitoring prognosis. We conducted a cross sectional study on 31 newly confirmed cases of Multiple Myeloma diagnosed by serum protein electrophoresis, bone marrow aspiration and biopsy in Mangalore. Electrolyte disturbances observed include hypercalcemia (13%), hyponatremia (42%) and hypokalemia (6%). Hypoalbuminemia was observed in 83% of cases. Renal impairment was seen in 58% cases. Serum osmolarity was low despite increased proteins. Electrolyte disturbances are not uncommon in multiple myeloma. Hyponatremia can be asymptomatic and demands careful evaluation before institution of therapy. It is important to measure serum osmolarity and osmolar gap and carefully decide the management of electrolyte imbalance in every case of multiple myeloma. The coexistent hyperproteinemia, hyperglycemia, hypertriglyceridemia and renal disease should be evaluated. Hyponatremia was common in our study group although association with proteins or renal disease was not statistically significant.