Defining hypercalciuria in nephrolithiasis.

Published

Journal Article (Review)

The classic definition of hypercalciuria, an upper normal limit of 200  mg/day, is based on a constant diet restricted in calcium, sodium, and animal protein; however, random diet data challenge this. Here our retrospective study determined the validity of the classic definition of hypercalciuria by comparing data from 39 publications analyzing urinary calcium excretion on a constant restricted diet and testing whether hypercalciuria could be defined when extraneous dietary influences were controlled. These papers encompassed 300 non-stone-forming patients, 208 patients with absorptive hypercalciuria type I (presumed due to high intestinal calcium absorption), and 234 stone formers without absorptive hypercalciuria; all evaluated on a constant restricted diet. In non-stone formers, the mean urinary calcium was well below 200  mg/day, and the mean for all patients was 127±46  mg/day with an upper limit of 219  mg/day. In absorptive hypercalciuria type I, the mean urinary calcium significantly exceeded 200  mg/day in all studies with a combined mean of 259±55  mg/day. Receiver operating characteristic curve analysis showed the optimal cutoff point for urinary calcium excretion was 172  mg/day on a restricted diet, a value that approximates the traditional limit of 200  mg/day. Thus, on a restricted diet, a clear demarcation was seen between urinary calcium excretion of kidney stone formers with absorptive hypercalciuria type I and normal individuals. When dietary variables are controlled, the classic definition of hypercalciuria of nephrolithiasis appears valid.

Full Text

Duke Authors

Cited Authors

  • Pak, CYC; Sakhaee, K; Moe, OW; Poindexter, J; Adams-Huet, B; Pearle, MS; Zerwekh, JE; Preminger, GM; Wills, MR; Breslau, NA; Bartter, FC; Brater, DC; Heller, HJ; Odvina, CV; Wabner, CL; Fordtran, JS; Oh, M; Garg, A; Harvey, JA; Alpern, RJ; Snyder, WH; Peters, PC

Published Date

  • October 2011

Published In

Volume / Issue

  • 80 / 7

Start / End Page

  • 777 - 782

PubMed ID

  • 21775970

Pubmed Central ID

  • 21775970

Electronic International Standard Serial Number (EISSN)

  • 1523-1755

International Standard Serial Number (ISSN)

  • 0085-2538

Digital Object Identifier (DOI)

  • 10.1038/ki.2011.227

Language

  • eng