Paricalcitol For CKD-MBD Associated With Secondary Hyperparathyroidism: A Case Series Focus On TRAP5b, b-ALP, and DKK-1

Abstract

Chronic kidney disease (CKD) lead to secondary hyperparathyroidism (sHPT) that caused by phosphate retention and hypocalcemia. This condition known as mineral and bone disorder (CKD-MBD). The increase in parathyroid hormone would increase bone turnover that result in an increased risk of bone fractures, and vascular calcification. These will increase the levels of tartrate-resistant acid phosphatase 5b (TRAP5b), and bone-specific alkaline phosphatase (b-ALP), which is a marker of bone turnover, and also dickkopf-related protein 1 (DKK-1), which is an inhibitor of the Wnt pathway. Secondary hyperparathyroidism in CKD also caused by calcitriol deficiency. Paricalcitol is a synthetic calcitrol analogue used to reduce parathyroid hormone (iPTH) with minimal calcemic and phosphatemic activity. Vitamin D receptor activation by paricalcitol will decrease TRAP5b, b-ALP, and DKK-1. In this study we reported 9 cases of CKD-MBD with Hemodialysis (HD) and associated with sHPT. Four of nine cases received 5μg paricalcitol every HD (twice a week) while the others five is not. Level of iPTH, phosphate, calcium, TRAP5b, b-ALP, and DKK-1 were measured before initiation of study and after three months treatment. According to this study, t he paricalcol administration suppresses the increase in iPTH level , bone turnover and vascular calcification showed by decreasing or supresses the increase b- ALP , TRAP5b , DKK-1 leves without increasing calcium and phosphate levels.