MP41-14 IMPACT OF URINE PH ON URINARY SUPERSATUATION OF CALCIUM OXALATE

Abstract

You have accessJournal of UrologyStone Disease: Medical Therapy1 Apr 2015MP41-14 IMPACT OF URINE PH ON URINARY SUPERSATUATION OF CALCIUM OXALATE Jodi A. Antonelli, Naim Maalouf, Jodi A. Antonelli, Monica S.C. Morgan, Adam Cohen, John Pointdexter, Beverley Adams-Huet, Khashayar Sakhaee, and Margaret S. Pearle Jodi A. AntonelliJodi A. Antonelli More articles by this author , Naim MaaloufNaim Maalouf More articles by this author , Jodi A. AntonelliJodi A. Antonelli More articles by this author , Monica S.C. MorganMonica S.C. Morgan More articles by this author , Adam CohenAdam Cohen More articles by this author , John PointdexterJohn Pointdexter More articles by this author , Beverley Adams-HuetBeverley Adams-Huet More articles by this author , Khashayar SakhaeeKhashayar Sakhaee More articles by this author , and Margaret S. PearleMargaret S. Pearle More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1642AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The role of urine pH in the formation of calcium oxalate stones is controversial. The benefit of increasing urine pH in calcium oxalate stone formers with low urine pH and normal urinary citrate is controversial. We sought to investigate the role of urine pH on estimates of urinary supersaturation by modeling and in a group of calcium oxalate stone formers with low urine pH and normal urinary citrate. METHODS Using mean values for urinary parameters derived from 1494 patients in our stone registry, we analyzed the effect of varying urine pH on estimates of urinary supersatuation over a range of urinary citrate while keeping other urinary parameters constant. We used 2 estimates of urinary supersaturation: relative saturation ratio (RSR) derived from EQUIL 2 and saturation index (SI) derived from JESS v8.2 (Joint Expert Speciation System). In addition, we obtained 24-hour urine values at baseline and after treatment with potassium citrate from 55 calcium oxalate stone formers with low urine pH (≤ 6.0) and normal urinary citrate (citrate ≥ 500 mg/day) and performed regression analysis, adjusting for calcium, oxalate, volume and citrate, to determine the independent effect of urine pH on RSR and SI calcium oxalate in this patient group. RESULTS Table 1 shows the results of the model. RSR and SI declined over a range of pH from 5.0 to 7.0 at all levels of urinary citrate when keeping the other urinary parameters constant. In the patient group, change in urine pH (from baseline to after treatment with potassium citrate) was a significant predictor of change in SI calcium oxalate (p=0.00125), but not of change in RSR calcium oxalate (p=0.413), with SI declining with increasing urine pH. CONCLUSIONS In a theoretical model, urine pH negatively correlated with urinary supersuration of calcium oxalate as estimated by RSR and SI. In a group of calcium oxalate stone formers with low pH and normal urinary citrate, treatment with potassium citrate reduced SI, but not RSR, independent of the effect on urinary citrate. Calcium oxalate stone formers may benefit from normalizing urine pH. The Effect of pH at Increasing Citrate levels pH 5.0 5.5 6.0 6.5 7.0 [Citrate] = 1.0 mmol/L SI CaOx 5.56 5.34 5.00 4.48 3.85 RSR CaOx 4.53 5.33 5.55 5.48 5.29 [Citrate] = 3.0 mml/L SI CaOx 4.37 3.98 3.48 2.77 1.76 RSR CaOx 3.90 4.24 4.14 3.93 3.73 [Citrate] = 5.0 SI CaOx 3.32 2.95 2.44 1.75 0.89 RSR CaOx 3.36 3.31 2.94 2.65 2.47 © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e505 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jodi A. Antonelli More articles by this author Naim Maalouf More articles by this author Jodi A. Antonelli More articles by this author Monica S.C. Morgan More articles by this author Adam Cohen More articles by this author John Pointdexter More articles by this author Beverley Adams-Huet More articles by this author Khashayar Sakhaee More articles by this author Margaret S. Pearle More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...