MP40-17 ASSESSING ALTERATIONS IN STONE BURDEN AMONG PATIENTS WITH MEDULLARY SPONGE KIDNEY: A VOLUMETRIC APPROACH

You have accessJournal of UrologyStone Disease: Epidemiology & Evaluation I (MP40)1 May 2024MP40-17 ASSESSING ALTERATIONS IN STONE BURDEN AMONG PATIENTS WITH MEDULLARY SPONGE KIDNEY: A VOLUMETRIC APPROACH Andrei D. Cumpanas, Victor Pham, Betty Nguyen, Jacob C. Tsai, Jaime Altamirano-Villarroel, Amanda McCormac, Paul Piedras, Bruce Gao, Zachary E. Tano, Pengbo Jiang, Roshan M. Patel, Jaime Landman, and Ralph V. Clayman Andrei D. CumpanasAndrei D. Cumpanas , Victor PhamVictor Pham , Betty NguyenBetty Nguyen , Jacob C. TsaiJacob C. Tsai , Jaime Altamirano-VillarroelJaime Altamirano-Villarroel , Amanda McCormacAmanda McCormac , Paul PiedrasPaul Piedras , Bruce GaoBruce Gao , Zachary E. TanoZachary E. Tano , Pengbo JiangPengbo Jiang , Roshan M. PatelRoshan M. Patel , Jaime LandmanJaime Landman , and Ralph V. ClaymanRalph V. Clayman View All Author Informationhttps://doi.org/10.1097/01.JU.0001008788.18007.3f.17AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Medullary sponge kidney (MSK) patients exhibit numerous calcifications within their kidneys, posing a formidable challenge in monitoring urolithiasis progression. Presently, accurate stone linear measurements are hindered by time constraints and high interobserver variability. Using the 3D Slicer® program to determine total stone volume, we sought to assess the accuracy of the year-to-year non-contrast computerized tomography (NCCT) report of "stable/unchanged" stone burden among MSK patients versus urolithiasis patients without an underlying renal disorder. METHODS: A retrospective review of our Kidney Stone Center Database from January 2018 to September 2023, revealed 70 patients with a "stable/unchanged" stone burden report on NCCT. Among these patients, 20 (40 renal units) had MSK and 50 (78 renal units) had no underlying renal disorder. NCCT 3D stone volume measurements were completed by a single physician reviewer with over 100 hours of experience and whose accuracy was validated against a gold-standard volumetric assessment with gas pycnometry. The reviewer was blinded with regard to the CT scans' dates.Among patients with a "stable/unchanged" report, we assessed the error rate in failing to detect a 15%, 25%, or 50% increase in stone volume. A two-tailed Chi-square analysis was used to compare the two patient groups. RESULTS: In the MSK group, stone burden increases of 15%, 25%, or 50% were missed in 49%, 39%, and 20% of cases, respectively (Figure 1). Moreover, an MSK diagnosis was significantly associated with incorrect assessments of "stable/unchanged" stone burden for all growth thresholds (p-values <0.03). This corresponded to a median stone growth of 297 mm3 (interquartile range: 128.88 – 745.55 mm3). Among non-MSK patients, the rate of "stable/unchanged" stone burden misclassification, while less than for MSK patients, was nonetheless significant: 15%, 25%, or 50% increase in stone burden was missed in 24%, 9%, and 7% of cases, respectively (p-values <0.03). CONCLUSIONS: Volumetric stone burden progression in the MSK population is significantly more common than among non-MSK patients. The increase in MSK stone burden on NCCT is often missed leading to a false sense of stable disease when in fact it is progressive. Download PPT Source of Funding: None © 2024 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 211Issue 5SMay 2024Page: e670 Advertisement Copyright & Permissions© 2024 by American Urological Association Education and Research, Inc.Metrics Author Information Andrei D. Cumpanas More articles by this author Victor Pham More articles by this author Betty Nguyen More articles by this author Jacob C. Tsai More articles by this author Jaime Altamirano-Villarroel More articles by this author Amanda McCormac More articles by this author Paul Piedras More articles by this author Bruce Gao More articles by this author Zachary E. Tano More articles by this author Pengbo Jiang More articles by this author Roshan M. Patel More articles by this author Jaime Landman More articles by this author Ralph V. Clayman More articles by this author Expand All Advertisement PDF downloadLoading ...