The effect of short-course gentamicin therapy on kidney function in patients with bacteraemia-a retrospective cohort study

The nephrotoxic potential of aminoglycosides is primarily correlated to the duration of therapy. However, there are discrepancies between previous studies regarding the effect of short course treatment. The aim of this study was to compare renal function, renal recovery and mortality in a large cohort of patients with bacteraemia, who were empirically treated with regimens with and without a short course (≤ 3 days) of once daily dosing of gentamicin. This was a retrospective propensity score-matched cohort study based on all patients with bacteraemia in a Danish hospital in the period 2010-2013. We included 702 patients who received gentamicin, and 702 who did not receive gentamicin. To determine the impact of gentamicin on renal function, we used a modified version of the Kidney Disease: Improving Global Outcomes (KDIGO) criteria for acute kidney injury (AKI), and the resulting data were analyzed by logistic regression. We used Cox regression analysis to compare the adjusted mortality rates between the two groups. According to the KDIGO criteria, we found no significant difference in the occurrence of AKI between the two groups (odds ratio (OR) 0.90 (95% CI 0.68-1.20)). We found that recovery of renal function was similar in the two groups, OR 1.00 (95% CI 0.63-1.60). The hazard ratio for 90-day all-cause mortality was 1.02 (95% CI 0.84-1.25). Short-course empirical gentamicin treatment of patients with bacteraemia was not associated with an increased incidence of AKI nor all-cause mortality in this study, and we observed similar reversibility of renal function.