Low-calcium dialysate improves mineral metabolism in hemodialysis patients

• Published in: Clinical nephrology Vol. 67; no. 1; p. 20
• Main Authors: Fujimori, A, Yorifuji, M, Sakai, M, Oyama, M, Nakao, N, Tokuyama, M, Fukagawa, M
• Format: Journal Article
• Language: English
• Published: Germany 01.01.2007
• Subjects: Acid Phosphatase - blood; Aged; Alkaline Phosphatase - blood; Calcium - administration & dosage; Calcium - blood; Female; Hemodialysis Solutions - chemistry; Humans; Isoenzymes - blood; Male; Parathyroid Hormone - blood; Phosphorus - blood; Renal Dialysis; Tartrate-Resistant Acid Phosphatase
• ISSN: 0301-0430
• DOI: 10.5414/CNP67020

The Kidney Disease Outcomes Quality Initiative (K/DOQI) Guidelines for Bone Metabolism and Disease in Chronic Kidney Disease recommend 1.25 mmol/l Ca dialysate for both hemodialysis and peritoneal dialysis, while 1.5 mmol/l Ca dialysate has been used in our dialysis center. Therefore, we switched the dialysate calcium concentration from 1.5 - 1.25 mmol/l and observed the effects on serum calcium (S-Ca), phosphorus (S-P), 1-84 parathyroid hormone (whole PTH, w-PTH), bone-specific alkaline phosphatase (BAP), and tartrate-resistant acid phosphatase isoform 5b (TRACP-5b) for 6 months in 58 hemodialysis patients. Prescription of active vitamin D (VD) metabolites and Ca carbonate was increased in response to the changes in laboratory data. Decrease of S-Ca was evident at 2 weeks and S-Ca remained low for 6 months. Transient elevation of S-P, which might be caused by stimulated bone resorption, was observed after the switch. In patients with low PTH (w-PTH less than 90 pg/ml before the switch), continuous increase of w-PTH, BAP, and TRACP-5b was observed. This appeared to be a favorable response because the risk ofadynamic bone disease was high in this group of patients. On the other hand, acute elevation of the 3 parameters was well-controlled in patients with moderate and high PTH (w-PTH from 90 - 180 pg/ml, w-PTH more than 180 pg/ml, respectively) by increased dosage of active VD. These results demonstrate that 1.25 mmol/l Ca dialysate improved mineral metabolism by lowering S-Ca and releasing oversuppression of PTH. Our data also suggest that appropriate use of active VD could prevent acute rise of PTH.