Plasma calcitonin concentration in patients treated with chronic dialysis: differences between hemodialysis and CAPD.

We have determined plasma calcitonin levels in 72 chronic dialysis patients and investigated their possible correlations with other parameters of calcium and phosphorus metabolism, including plasma levels of calcium, phosphorus, alkaline phosphatase and parathormone, as well as with the duration of treatment. Forty-one of the patients were being treated with hemodialysis (HD) and thirty-one with continuous ambulatory peritoneal dialysis (CAPD). Increased calcitonin levels were detected in 83% of the HD patients and in 79% of the CAPD group. In the former there was a positive correlation between the levels of calcitonin and the calcium, corrected calcium, alkaline phosphatase and parathormone levels and with the duration of treatment, whereas in the latter the calcitonin levels only correlated with the serum calcium. The patients receiving CAPD also showed significantly lower calcium and calcitonin levels than the HD patients. Our conclusion is that, apart from accumulation due to renal failure, the main factor determining the calcitonin level is the blood calcium level, and that the observed increase might play a role in the physiological protection of bone against the action of parathyroid hormone.