Microscopic nephrocalcinosis in chronic kidney disease patients.

Abstract

BACKGROUND:

Experimental data indicate that microscopic calcium phosphate deposition in the kidney (nephrocalcinosis) may accelerate progression of chronic kidney disease (CKD). Data on the prevalence, risk factors and implications of nephrocalcinosis in CKD patients are scarce. A mineral metabolism disorder could play an important pathogenetic role, as suggested by recent protocol biopsy findings in incident renal transplant recipients.

METHODS:

Kidney biopsy cylinders of CKD patients, collected between January 1989 and December 2007, were screened for the presence of nephrocalcinosis. Only patients with ≥1 parathyroid hormone (PTH) level available within 180 days of the biopsy were eligible for inclusion (n = 211). Demographics and mineral metabolism parameters were retrieved from medical files. Data on renal death (up to December 2012) were obtained from the Flemish ESRD registry. Baseline biopsies from 110 deceased kidney transplant donors served as controls.

RESULTS:

The prevalence of nephrocalcinosis in kidney donors and patients with CKD 1-2, CKD 3-4 and CKD 5-5D was 4.6, 14.3, 20.2 and 54.0%, respectively (P < 0.0001). Among CKD patients, patients with nephrocalcinosis were characterized by lower estimated GFR, lower serum bicarbonate level and higher serum PTH and calcium level. In multivariate regression analysis, high serum PTH, calcium and creatinine level, and low serum bicarbonate level were all significantly and independently associated with nephrocalcinosis. Serum phosphorus level, but not nephrocalcinosis predicted renal death, independent of renal function.

CONCLUSIONS:

Our data demonstrate that prevalence rates of nephrocalcinosis increase with increasing CKD stage to reach more than 50% in end-stage renal disease patients and suggest that acid-base and mineral metabolism disturbances are implicated in its pathogenesis.

• Authors: Pieter Evenepoel, Kristien Daenen, Bert Bammens, Kathleen Claes, Björn Meijers, Maarten Naesens, Ben Sprangers, Dirk Kuypers, Eveline Lerut
• Journal: Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (Nephrol Dial Transplant) Vol. 30 Issue 5 Pg. 843-8 (May 2015) ISSN: 1460-2385 [Electronic] England
• PMID: 25586405 (Publication Type: Journal Article, Observational Study)
• Copyright: © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Chemical References

• Parathyroid Hormone
• Phosphates
• Creatinine
• Calcium

Topics

• Adult
• Aged
• Biopsy
• Calcium (blood)
• Creatinine (blood)
• Disease Progression
• Female
• Glomerular Filtration Rate
• Humans
• Male
• Middle Aged
• Multivariate Analysis
• Nephrocalcinosis (complications, epidemiology)
• Parathyroid Hormone (blood)
• Phosphates (blood)
• Prevalence
• Registries
• Renal Insufficiency, Chronic (complications, epidemiology)
• Retrospective Studies
• Risk Factors