Preoperative risk factors in patients with xanthogranulomatous pyelonephritis undergoing nephrectomy

Abstract

Objective: To identify preoperative risk factors associated with major complications in patients with xanthogranulomatous pyelonephritis undergoing total nephrectomy. Method: Retrospective analysis of patient’s charts with xanthogranulomatous pyelonephritis who underwent nephrectomy. Risk factors included for analysis were gender, body mass index, Charlson co-morbidity index, American Society of Anesthesiologists physical status classification, Malek’s stage, leukocyte count and creatinine levels. Postoperative complications were stratified in minor and major according to Clavien-Dindo’s classification. Univariate and bivariate analysis using Fisher’s exact test, Pearson’s chi-squared and odds ratio (OR) was performed. Results: 72 patients were analyzed, 83% women, mean age of 50 years, 58.3% positive urine cultures and 66% kidney stones. Major complications were present in 32% of cases, and 15% were admitted to the intensive care unit. Elevated creatinine (OR: 3.8; 95% confidence interval [95%CI]: 1.1-13; p = 0.02) and Malek’s stage II to III (OR: 4.5; 95%CI: 1.2-17.5; p = 0.02) were associated with major complications. Conclusion: The Malek Stage and elevated creatinine increases the risk of major complications in patients undergoing nephrectomy due to xanthogranulomatous pyelonephritis.