Does calcitriol therapy improve muscle function in uremic patients.

The purpose of the present study is to investigate whether calcitriol therapy in uremic patients undergoing dialysis treatment can improve muscle function. In 8 uremic patients [2 on continuous ambulatory peritoneal dialysis (CAPD), 6 on hemodialysis (HD) treatment], calcitriol (Calcitriol, Roche) was given in the dose of 1 microgram/day for 15 months. At the beginning of therapy and every month, the following parameters in serum were determined: creatinine (Cr), calcium (Ca), phosphate (P), and parathyroid hormone (PTH). At the beginning and at the end of treatment, quantitative electromyography (EMG) was performed. We observed a slight increase of serum Cr during 15 months of treatment in 4 patients. Serum Ca, P, and PTH did not change significantly. The EMG revealed abnormal polyphasic motor nerve unit potentials of brief durations, a decrease in the amplitude, and fibrillation potentials. The EMG findings did not change significantly after calcitriol therapy, but all patients on physical examinations exhibited the disappearance of clinical manifestations of uremic myopathy. In conclusion, our findings suggest that vitamin D deficiency is one of the causes of uremic myopathy and a careful treatment with calcitriol can diminish muscle weakness in uremic patients.