Incidence of nephrotoxicity associated with intravenous colistimethate sodium administration for the treatment of multidrug‑resistant gram‑negative bacterial infections Sadyrbaeva Dolgova, Svetlana Expósito Ruiz, Manuela Pasquau Liaño, Juan Jiménez Morales, Alberto Hidalgo Tenorio, Carmen Colistimethate sodium (CMS) is the inactive prodrug of colistin, CMS has a narrow antibacterial spectrum with concentration-dependent bactericidal activity against multidrug-resistant gramnegative bacteria, including Pseudomonas aeruginosa and Acinetobacter baumannii. This study aimed to analyze potential correlations between clinical features and the development of CMS-induced nephrotoxicity. This retrospective cohort study was conducted in a tertiary-care university hospital between 1 January 2015 and 31 December 2019. A total of 163 patients received CMS therapy. 75 patients (46%) developed nephrotoxicity attributable to colistin treatment, although only 14 patients (8.6%) discontinued treatment for this reason. 95.7% of CMS were prescribed as target therapy. Acinetobacter baumannii spp. was the most commonly identified pathogen (72.4%) followed by P. aeruginosa (19.6%). Several risk factors associated with nephrotoxicity were identified, among these were age (HR 1.033, 95%CI 1.016–1.052, p < 0.001), Charlson Index (HR 1.158, 95%CI 1.0462– 1.283; p = 0.005) and baseline creatinine level (HR 1.273, 95%CI 1.071–1.514, p = 0.006). In terms of in-hospital mortality, risk factors were age (HR 2.43, 95%CI 1.021–1.065, p < 0.001); Charlson Index (HR 1.274, 95%CI 1.116–1.454, p = 0.043), higher baseline creatinine levels (HR 1.391, 95%CI 1.084– 1.785, p = 0.010) and nephrotoxicity due to CMS treatment (HR 5.383, 95%CI 3.126–9.276, p < 0.001). In-hospital mortality rate were higher in patients with nephrotoxicity (log rank test p < 0.001). In conclusion, the nephrotoxicity was reported in almost half of the patients. Its complex management, continuous renal dose adjustment and monitoring creatinine levels at least every 48 h leads to a high percentage of inappropriate use and treatment failure. 2022-10-06T12:21:45Z 2022-10-06T12:21:45Z 2022-09-10 journal article Sadyrbaeva-Dolgova, S... [et al.]. Incidence of nephrotoxicity associated with intravenous colistimethate sodium administration for the treatment of multidrug-resistant gram-negative bacterial infections. Sci Rep 12, 15261 (2022). [https://doi.org/10.1038/s41598-022-19626-2] https://hdl.handle.net/10481/77203 10.1038/s41598-022-19626-2 eng http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional Nature