Urological Research

, Volume 38, Issue 6, pp 421–427

Nephrocalcinosis: re-defined in the era of endourology

  • Nicole L. Miller
  • Mitchell R. Humphreys
  • Fredric L. Coe
  • Andrew P. Evan
  • Sharon B. Bledsoe
  • Shelly E. Handa
  • James E. Lingeman
SYMPOSIUM PAPER

DOI: 10.1007/s00240-010-0328-8

Cite this article as:
Miller, N.L., Humphreys, M.R., Coe, F.L. et al. Urol Res (2010) 38: 421. doi:10.1007/s00240-010-0328-8

Abstract

Nephrocalcinosis generally refers to the presence of calcium salts within renal tissue, but this term is also used radiologically in diagnostic imaging in disease states that also produce renal stones, so that it is not always clear whether it is tissue calcifications or urinary calculi that give rise to the characteristic appearance of the kidney on x-ray or computed tomography (CT). Recent advances in endoscopic imaging now allow the visual distinction between stones and papillary nephrocalcinosis, and intrarenal endoscopy can also verify the complete removal of urinary stones, so that subsequent radiographic appearance can be confidently attributed to nephrocalcinosis. This report shows exemplary cases of primary hyperparathyroidism, type I distal renal tubular acidosis, medullary sponge kidney, and common calcium oxalate stone formation. In the first three cases—all being conditions commonly associated with nephrocalcinosis—it is shown that the majority of calcifications seen by radiograph may actually be stones. In common calcium oxalate stones formers, it is shown that Randall’s plaque can appear as a small calculus on CT scan, even when calyces are known to be completely clear of stones. In the current era with the use of non-contrast CT for the diagnosis of nephrolithiasis, the finding of calcifications in close association with the renal papillae is common. Distinguishing nephrolithiasis from nephrocalcinosis requires direct visual inspection of the papillae and so the diagnosis of nephrocalcinosis is essentially an endoscopic, not radiologic, diagnosis.

Keywords

Kidney calculi Nephrocalcinosis Medullary sponge Renal tubular acidosis Hyperparathyroidism 

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Nicole L. Miller
    • 1
  • Mitchell R. Humphreys
    • 2
  • Fredric L. Coe
    • 3
  • Andrew P. Evan
    • 4
  • Sharon B. Bledsoe
    • 4
  • Shelly E. Handa
    • 5
  • James E. Lingeman
    • 6
  1. 1.Vanderbilt University Medical Center, Department of Urologic SurgeryNashvilleUSA
  2. 2.Mayo ClinicPhoenixUSA
  3. 3.Nephrology SectionUniversity of ChicagoChicagoUSA
  4. 4.Department of Anatomy and Cell BiologyIndiana University School of MedicineIndianapolisUSA
  5. 5.Methodist Hospital for Kidney Stone DiseaseIndianapolisUSA
  6. 6.Methodist Hospital for Kidney Stone Disease, Urology SectionIndianapolisUSA