Percutaneous maxacalcitol (OCT) injection therapy (PMIT) has been developed as an effective and safe treatment for advanced secondary hyperparathyroidism (SHPT). The effect of PMIT on PTH suppression was evaluated by intact PTH, highly sensitive (HS) PTH, and whole PTH assays.
Eight dialysis patients with SHPT resistant to intravenous OCT administrations were consecutively treated by PMIT six times a week followed by OCT intravenous administrations (iv OCT). Serum intact PTH, HS PTH, whole PTH, Ca adjusted for albumin, and P levels were measured before, immediately, 4 and 12 weeks after PMIT.
After PMIT, serum intact PTH, HS PTH, and whole PTH levels were significantly decreased, however serum adjusted Ca and P levels did not change significantly. Whole PTH/C PTH (calculated by intact-PTH-whole PTH) ratio was also significantly decreased immediately after PMIT. In five patients whose PTH levels were controlled by iv OCT for more than 6 months after PMIT (effective group), the decrease in whole PTH level after PMIT was significantly greater compared with that in the ineffective group whose PTH levels could not be controlled by iv OCT.
It is suggested that whole PTH difference immediately after PMIT compared to that before may predict the effect of PMIT.