2081 DOES STONE COMPOSITION CHANGE IN RECURRENT STONE-FORMERS?

Abstract

You have accessJournal of UrologyStone Disease: Basic Research (I)1 Apr 20132081 DOES STONE COMPOSITION CHANGE IN RECURRENT STONE-FORMERS? Terence Lee, Mohamed Elkoushy, and Sero Andonian Terence LeeTerence Lee Montreal, Canada More articles by this author , Mohamed ElkoushyMohamed Elkoushy Montreal, Canada More articles by this author , and Sero AndonianSero Andonian Montreal, Canada More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.2500AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES To assess the prevalence of changes in stone composition of recurrent stone-formers. METHODS A retrospective review of 303 patients with confirmed stone analysis presenting to a tertiary stone clinic between July 2009 and June 2012. All stones were analyzed at one centralized laboratory using infrared spectrophotoscopy. Stone type was defined as the predominant stone component of at least 60%. Patients were grouped together according to the first predominant stone type on record. In the mixed stone group, there was no predominant stone composition. Calcium oxalate monohydrate and dihydrate were grouped as calcium oxalate (CaOx). Uric acid (UA) stones included uric acid dihydrate and ammonium urate while calcium phosphate, brushite and struvite were grouped as phosphate (Ph) stones. Patient records including operative reports and imaging studies were reviewed. Patients with multiple stone analyses at least 3 months apart were considered recurrent stone-formers and included in the study. RESULTS The cohort of 303 patients had a mean age of 54.3±30.7 years and 207 (68.3%) were males. The initial stone analysis showed: 145 (47.9%) CaOx, 88 (29%) Ph, 46 (15.2%) UA, 9 (3%) cystine and 15 (5%) mixed. There were 41 (13.5%) recurrent stone-formers with a median time of 404 days. Stone composition changed in 29.3% of recurrent stone-formers. Out of 13 patients with initial CaOx stones, 4 (30.8%) changed to another type (1 mixed, 2 UA, 1 Ph). Out of 11 patients with initial UA stones, 4 (36%) changed to another type (1 mixed and 3 CaOx). Out of 10 patients with initial Ph stones, 1 (10%) changed to CaOx, whereas all 3 patients with mixed stones changed to predominant CaOx, UA and Ph stones (1 patient each). None of the 4 cystinuric patients changed stone composition. CONCLUSIONS Stone composition may significantly change in subsequent stone analysis in recurrent stone-formers. Therefore, stone analysis is recommended on each stone episode. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e854 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Terence Lee Montreal, Canada More articles by this author Mohamed Elkoushy Montreal, Canada More articles by this author Sero Andonian Montreal, Canada More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...