Elimination and penetration of amikacin into urine in patients with decreased glomerular filtration rate

Abstract

Background. Amikacin monotherapy is recommended for urinary tract infection (UTI) treatment with multi-resistant pathogens. Even though amikacin efficacy in the treatment of UTIs is dependent on its urinary concentration, there are no robust data proving that sufficiently high urinary concentration is reached in patients with reduced glomerular filtration rate (GFR). Methods. A prospective study to monitor amikacin penetration into urine of 70 patients [40 males, median (interquartile range) age 70 (65–79) years] with different levels of glomerular filtration decline, including patients treated by dialysis, was conducted. The bactericidal efficacy of amikacin in urine samples has been evaluated. Results. Patients with estimated GFR (eGFR) <30 mL/min had significantly lower median amikacin urinary concentration than patients with eGFR >30 mL/min (89.75 vs 186.0 mg/L, P < .0001 for minimal, maximal and minimal together with maximal concentrations, respectively). The amount of amikacin eliminated in the first 10–13 h after dose administration was dependent on eGFR (r2 = 0.6144, P