Impact of Potassium Citrate vs Citric Acid on Urinary Stone Risk in Calcium Phosphate Stone Formers

No AccessJournal of UrologyAdult Urology1 Dec 2018Impact of Potassium Citrate vs Citric Acid on Urinary Stone Risk in Calcium Phosphate Stone Formers Steeve Doizi, John R. Poindexter, Margaret S. Pearle, Francisco Blanco, Orson W. Moe, Khashayar Sakhaee, and Naim M. Maalouf Steeve DoiziSteeve Doizi Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Current address: Sorbonne Université, GRC n°20, Groupe de Recherche Clinique sur la Lithiase Urinaire, Hôpital Tenon, F-75020 Paris, France. More articles by this author , John R. PoindexterJohn R. Poindexter Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author , Margaret S. PearleMargaret S. Pearle Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author , Francisco BlancoFrancisco Blanco Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author , Orson W. MoeOrson W. Moe Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas Division of Nephrology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author , Khashayar SakhaeeKhashayar Sakhaee Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Division of Mineral Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author , and Naim M. MaaloufNaim M. Maalouf Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Division of Mineral Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.07.039AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: To our knowledge no medication has been shown to be effective for preventing recurrent calcium phosphate urinary stones. Potassium citrate may protect against calcium phosphate stones by enhancing urine citrate excretion and lowering urine calcium but it raises urine pH, which increases calcium phosphate saturation and may negate the beneficial effects. Citric acid can potentially raise urine citrate but not pH and, thus, it may be a useful countermeasure against calcium phosphate stones. We assessed whether these 2 agents could significantly alter urine composition and reduce calcium phosphate saturation. Materials and Methods: In a crossover metabolic study 13 recurrent calcium phosphate stone formers without hypercalciuria were evaluated at the end of 3, 1-week study phases during which they consumed a fixed metabolic diet and received assigned study medications, including citric acid 30 mEq twice daily, potassium citrate 20 mEq twice daily or matching placebo. We collected 24-hour urine specimens to perform urine chemistry studies and calculate calcium phosphate saturation indexes. Results: Urine parameters did not significantly differ between the citric acid and placebo phases. Potassium citrate significantly increased urine pH, potassium and citrate compared to citric acid and placebo (p <0.01) with a trend toward lower urine calcium (p = 0.062). Brushite saturation was increased by potassium citrate when calculated by the relative supersaturation ratio but not by the saturation index. Conclusions: Citric acid at a dose of 60 mEq per day did not significantly alter urine composition in calcium phosphate stone formers. The long-term impact of potassium citrate on calcium phosphate stone recurrence needs to be studied further. References 1 : Composition and morphology of phosphate stones and their relation with etiology. Urol Res2010; 38: 459. Google Scholar 2 : Conversion of calcium oxalate to calcium phosphate with recurrent stone episodes. J Urol2003; 169: 2026. Link, Google Scholar 3 : Clinical implications of abundant calcium phosphate in routinely analyzed kidney stones. Kidney Int2004; 66: 777. Google Scholar 4 : Profile of the brushite stone former. 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Google Scholar © 2018 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetailsCited byWong D, Elson L, Nottingham C and Desai A (2022) Pharmaceutical versus Over-the-Counter Potassium Citrate: A Benchtop ComparisonUrology Practice, VOL. 9, NO. 3, (205-211), Online publication date: 1-May-2022.Assimos D (2020) Re: Urinary Lithogenic Risk Profile in ADPKD Patients Treated with TolvaptanJournal of Urology, VOL. 204, NO. 5, (1090-1091), Online publication date: 1-Nov-2020.Assimos D (2019) Re: Chlorthalidone is Superior to Potassium Citrate in Reducing Calcium Phosphate Stones and Increasing Bone Quality in Hypercalciuric Stone-Forming RatsJournal of Urology, VOL. 203, NO. 1, (26-26), Online publication date: 1-Jan-2020.Assimos D (2019) Re: The Impact of Potassium Citrate Therapy in the Natural Course of Medullary Sponge Kidney with Associated NephrolithiasisJournal of Urology, VOL. 202, NO. 6, (1091-1092), Online publication date: 1-Dec-2019.Assimos D (2019) Re: Hydroxycitrate: A Potential New Therapy for Calcium UrolithiasisJournal of Urology, VOL. 202, NO. 3, (454-455), Online publication date: 1-Sep-2019. Volume 200Issue 6December 2018Page: 1278-1284Supplementary Materials Advertisement Copyright & Permissions© 2018 by American Urological Association Education and Research, Inc.Keywordscalcium phosphatesurolithiasisurinary tractcitric acidpotassium citrateMetricsAuthor Information Steeve Doizi Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Current address: Sorbonne Université, GRC n°20, Groupe de Recherche Clinique sur la Lithiase Urinaire, Hôpital Tenon, F-75020 Paris, France. More articles by this author John R. Poindexter Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author Margaret S. Pearle Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author Francisco Blanco Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author Orson W. Moe Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas Division of Nephrology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author Khashayar Sakhaee Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Division of Mineral Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author Naim M. Maalouf Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas Division of Mineral Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas More articles by this author Expand All Advertisement PDF downloadLoading ...