Evaluation of colistin nephrotoxicity and urinary level of kidney injury molecule-1 in hospitalized adult ICU patients

Introduction: Colistin is a cationic polypeptide antibiotic used for treatment of gram-negative infections. Nephrotoxicity is one of the most common adverse effects of colistin. Objectives: To determine the epidemiology of colistin nephrotoxicity and also to compare the changing pattern of kidney injury molecule 1 (KIM-1) in urine with serum creatinine and urine during the treatment with colistin in patients admitted to intensive care unit (ICU). Patients and Methods: During 13 months, all patients admitted to adult ICUs of two university hospitals without any documented history of acute or chronic kidney diseases receiving at least one week of colistin were included. Required demographic, clinical, and paraclinical data of the study population was collected. Urinary and serum levels of creatinine, urea, sodium, potassium, magnesium, and KIM-1 were measured at six time points including days zero, 3, 5, 7, 10, and 14 of colistin treatment. Results: Six patients (18.18%) developed nephrotoxicity during colistin treatment. Nephrotoxicity was resolved without any intervention in three individuals. None of studied demographic, clinical and laboratory characteristics of the patients had a significant association with the incidence of colistin nephrotoxicity. The pattern of KIM-1 urine level during the course of colistin treatment did not differ significantly among patients with and without nephrotoxicity. The accuracy of KIM-1 urine level in detecting colistin nephrotoxicity was significantly lower than that of serum creatinine on days 0th, 3rd, 5th and 7th. Conclusion: Nephrotoxicity of colistin is a common complication, usually reversible, KIM-1 was not more accurate than serum creatinine or urine in detecting nephrotoxicity of colistin.