[Effect of pulse therapy using 1 alpha(OH)D on secondary hyperparathyroidism in patients on maintenance hemodialysis]

The effect of pulse therapy on severe secondary hyperparathyroidism related to chronic renal failure has been examined in 11 patients on maintenance hemodialysis by using an oral administration of 8 micrograms of 1 alpha(OH)D maximum per week. Throughout the 10 months of this treatment, the serum levels of intact-PTH, HS-PTH, and C-PTH were followed up. Additionally, to estimate the peak level of 1,25(OH)2D, its serum concentration at 10 hours after the 1 alpha (OH)D ingestion was measured. Results have shown that the serum levels of the intact-PTH, HS-PTH, and C-PTH were lowered in 9 of these 11 patients, two of this number especially showing a marked suppression of the serum intact-PTH to a low that was near to the normal upper limit level. In the two other cases of these 11 patients, no suppression was seen in any of serum PTH levels throughout the 10 months. In the cases that showed a good response, the 1,25(OH)2D serum concentration elevated significantly, to more than 100 pg/ml at 10 hours after the 1 alpha (OH)D intake. In contrast, in the 2 cases that showed no response, no appreciable elevation in the serum concentrations was noted. Thus, since the pulse therapy using 1 alpha (OH)D decreased the serum levels of the intact-PTH, HS-PTH, and C-PTH in 9 out of the 11 cases, we have concluded that pulse therapy using 1 alpha(OH)D is a valid therapy for secondary hyperparathyroidism in patients on maintenance hemodialysis.