Phenotypic characterization of kidney stone formers by endoscopic and histological quantification of intrarenal calcification.

TitlePhenotypic characterization of kidney stone formers by endoscopic and histological quantification of intrarenal calcification.
Publication TypeJournal Article
Year of Publication2013
AuthorsLinnes MP, Krambeck AE, Cornell L, Williams JC, Korinek M, Bergstralh EJ, Li X, Rule AD, McCollough CM, Vrtiska TJ, Lieske JC
JournalKidney international
Volume84
Issue4
Pagination818-25
Date Published2013 Oct
Abstract

Interstitial Randall's plaques and collecting duct plugs are distinct forms of renal calcification thought to provide sites for stone retention within the kidney. Here we assessed kidney stone precursor lesions in a random cohort of stone formers undergoing percutaneous nephrolithotomy. Each accessible papilla was endoscopically mapped following stone removal. The percent papillary surface area covered by plaque and plug were digitally measured using image analysis software. Stone composition was determined by micro-computed tomography and infrared analysis. A representative papillary tip was biopsied. The 24-h urine collections were used to measure supersaturation and crystal growth inhibition. The vast majority (99%) of stone formers had Randall's plaque on at least 1 papilla, while significant tubular plugging (over 1% of surface area) was present in about one-fifth of patients. Among calcium oxalate stone formers the amount of Randall's plaque correlated with higher urinary citrate levels. Tubular plugging correlated positively with pH and brushite supersaturation but negatively with citrate excretion. Lower urinary crystal growth inhibition predicted the presence of tubular plugging but not plaque. Thus, tubular plugging may be more common than previously recognized among patients with all types of stones, including some with idiopathic calcium oxalate stones.

DOI10.1093/infdis/jit235
Alternate JournalKidney Int.