PD32-04 METABOLIC EVALUATION IN PATIENTS WITH STRUVITE STONES: IS IT INDICATED?

Abstract

You have accessJournal of UrologyStone Disease: Evaluation II1 Apr 2014PD32-04 METABOLIC EVALUATION IN PATIENTS WITH STRUVITE STONES: IS IT INDICATED? Muhammad Iqbal, Ramy Youssef, Richard Shin, Fernando Cabrera, Jonathan Hanna, Charles Scales, Michael Ferrandino, Glenn Preminger, and Michael Lipkin Muhammad IqbalMuhammad Iqbal More articles by this author , Ramy YoussefRamy Youssef More articles by this author , Richard ShinRichard Shin More articles by this author , Fernando CabreraFernando Cabrera More articles by this author , Jonathan HannaJonathan Hanna More articles by this author , Charles ScalesCharles Scales More articles by this author , Michael FerrandinoMichael Ferrandino More articles by this author , Glenn PremingerGlenn Preminger More articles by this author , and Michael LipkinMichael Lipkin More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.2275AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES After surgical intervention, most patients with struvite stones receive low dose antibiotics and urease inhibitors to prevent recurrence. However, they typically do not undergo metabolic evaluation on the pretext of low occurrence of abnormalities. We report our experience with metabolic evaluation and directed medical therapy of patients with struvite stones. METHODS Between 1/2005 and 9/2012, 56 patients treated with percutaneous nephrolithotomy for struvite stones were identified. 7 had pure struvite stones with metabolic evaluation (Group 1), 32 had mixed struvite stones with metabolic evaluation (Group 2), and 17 had pure struvite stones without metabolic evaluation (Group 3). The frequency of metabolic abnormalities and stone activity (defined as stone growth or stone related events) were compared between groups. We used Fisher’s exact and the Kruskal-Wallis tests as appropriate with a Bonferroni correction for multiple comparisons. RESULTS The median age was 55 years (IQR 42-63.5) and 64% were female. No significant difference in demographics including race, UTI history, prior stone episodes, family history, stone location or volume existed between groups. Metabolic abnormalities were found in 57% of Group 1 and 81% of Group 2 patients (Table1). A similar proportion of Group 1 and 2 patients received modification to or continuation of metabolic therapy (86% and 88%, respectively) whereas no Group 3 patients received any such directed therapy. In patients with > 6 months follow up, the stone activity rate between Groups 1 and 2 appeared similar whereas Group 3 trended towards higher stone activity (20%, 30% and 50%, respectively) (Table2). CONCLUSIONS Metabolic abnormalities in struvite stone formers including patients with pure struvite stones appear to be more common than previously reported. Although likely underpowered, our findings appear clinically significant. While a larger study is needed, metabolic evaluation and directed medical therapy may be considered for patients with pure struvite stones. Table 1: Metabolic abnormalities and therapy by group. Pure +eval Mixed +eval Pure no eval P value Group number 1 2 3 Patients (n) 7 32 17 Metabolic abnormalities Any (n) 4 (57%) 26 (81%) - 0.319 Hyper Ca (n) 3 (43%) 12 (38%) - 1 Hyper Ox (n) 2 (29%) 5 (16%) - 0.588 Hyper Ur (n) 2 (29%) 12 (38%) - 1 Gouty D (n) 0 (0%) 4 (13%) - 1 Hypo Cit (n) 1 (14%) 13 (41%) - 0.386 Table2: Struvite patient outcomes by group. Pure + eval Mixed + eval Pure no eval P value Group number 1 2 3 Patients (n) 5 20 12 Stone free (n) 2 (40%) 9 (45%) 4 (33%) 0.89 Stone activity (n) 1 (20%) 6 (30%) 6 (50%) 0.45 Time to activity (mo) 15 19 (IQR: 18-32) 17 (IQR: 9-22) 0.55 © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e837 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Muhammad Iqbal More articles by this author Ramy Youssef More articles by this author Richard Shin More articles by this author Fernando Cabrera More articles by this author Jonathan Hanna More articles by this author Charles Scales More articles by this author Michael Ferrandino More articles by this author Glenn Preminger More articles by this author Michael Lipkin More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...