Objective: To compare the effective calcitriol regimens in hypocalcimic hyperparathyroidism (HPT) patients who were referred to parathyroidectomy.

Material and Method: Retrospective study of fifty patients who underwent parathyroidectomy in Rajavithi Hospital between September 2001 and August 2009 was performed. The authors defined three regimens of calcitriol (A; fixed dose regimen, B; titrated dose regimen and C; loading dose regimen) by reviewing 41 charts of patients with chronic kidney disease. Biochemical factors available within two weeks before and after surgery were recorded and analyzed.

Results: Postoperative hypocalcemia was a common complication found in 82.93% (n = 34/41) of patients with chronic kidney disease, 80.61% (n = 25/31) and 90% (n = 9/10) of secondary HPT and tertiary HPT, respectively. In multiple logistic regression analysis; calcium-phosphorus product was the independent predictor of postoperative hypocalcemia requiring intravenous calcium gluconate with statistical significance at p = 0.008, ROC analysis showed calcium phosphorus products more than 53 mg2/dl2 represented the best compromise between sensitivity (0.71) and specificity (0.67) by area under the curve = 0.755). The amount of intravenous calcium gluconate after parathyroidectomy in the loading calcitriol regimen (initial dose 2.25-4 mcg/day) was significantly lower than that in the titrated calcitriol regimen (0.75-1.5 mcg/day) (p = 0.001).

Conclusion: Loading calcitriol regimen reduced hypocalcemic morbidity in postoperative parathyroidectomy in patients with chronic kidney disease.

Keywords: Calcitriol, Parathyroidectomy, Chronic kidney disease