Acute Kidney Injury After Nephrotoxic Antibiotic Therapy in Patients with Infective Endocarditis

Acute kidney injury (AKI) due to antibiotic nephrotoxicity is a complication that can be avoided or managed properly if diagnosed early.

We aimed to determine the incidence and risk factors of AKI and to assess the possible effects of nephrotoxic antibiotic therapy on its development in a large group of patients with infective endocarditis (IE).

Patients with definite or possible IE diagnosed based on the Duke criteria were included in this retrospective cohort study at a tertiary referral center from 2007 to 2017. Data were derived from the single-center Iranian Registry of Infective Endocarditis (IRIE). Baseline risk factors for AKI were assessed via repeated serum creatinine measurements. Patients (n = 22) with end-stage renal failure undergoing dialysis were excluded. AKI was defined and staged in accordance with the Kidney Disease: Improving Global Outcomes (KDIGO) classification.

Totally, 498 patients at a mean age of 45 ± 16 years were studied. The baseline creatinine level was 1.26 ± 0.72 mg/dL. AKI occurred in 126 (26.3%) patients 1 week after the initiation of antibiotic therapy. There was a significant relationship between AKI and the use of gentamicin (P = 0.01) and gentamicin and vancomycin concomitantly (P = 0.01). At the end of the treatment, after dose adjustment and additional treatments, the incidence of AKI decreased to 22.7%, whereas this improvement was less remarkable in the patients with prior renal failure. Some independent variables, including age (P = 0.04), diabetes (P < 0.0001), prior renal failure (creatinine > 2 mg/dL), anemia (P = 0.003), left-sided IE (P = 0.04), and positive blood cultures with Staphylococcus aureus (P = 0.04) had a statistically significant association with AKI.

Close monitoring of the renal function is essential in IE patients receiving treatment with nephrotoxic antibiotics, especially patients with advanced age, diabetes, chronic renal failure, anemia, and left-sided IE.