Risk factors for nephrotoxicity associated with polymyxin B therapy in Chinese patients

Background The widespread application of Polymyxin B, an active agent against multidrug resistance and extensive drug resistance Gram-negative bacteria, is majorly impeded by nephrotoxicity. Studies on the safety of polymyxin B in Chinese patients have not been widely reported. Objective This study aimed to explore the risk factors for polymyxin B-associated nephrotoxicity and guide its optimal place in therapy. Setting A tertiary care hospital located in eastern China. Methods This being a retrospective cohort study, we evaluated adult patients who received ≥ 72 h of polymyxin B therapy from January 2018 to December 2019. However, patients who received polymyxin B therapy for less than 3 days or received renal replacement therapy at baseline were excluded. Pertinent information was retrieved from medical records. All statistical analysis was performed in SPSS version 22.0. Main outcome measure(s) The main outcome measures included the proportion of patients who developed nephrotoxicity when subjected to polymyxin B treatment and the independent risk factors for nephrotoxicity. Results A total of 119 patients received polymyxin and met the overall inclusion criterion. Of the 119, 46 patients (38.7%) developed nephrotoxicity. Through multiple logistic regression analysis, we found three variables as independent risk factors for nephrotoxicity, including co-morbidities of malignancy (OR 4.55; 95% CI 1.44-14.41; P = 0.010), co-infection with other microorganisms (OR 4.15; 95% CI 1.48-11.63; P = 0.007), and polymyxin B daily dose (OR 1.02; 95% CI 1.00-1.03; P = 0.026). Conclusion This retrospective cohort study identified three risk factors for polymyxin B-associated nephrotoxicity therapy in Chinese patients. These include malignancy, co-infection with other microorganisms, and polymyxin B daily dose.