[Acute renal failure related to intravenous acyclovir]

The aim of this study was to evaluate the incidence and outcome of acute renal failure (ARF) in patients submitted to intravenous (IV) acyclovir treatment.

All patients over 13 years of age that used intravenous acyclovir for 5 or more days were retrospectively analyzed. When serum creatinine levels, previously in the normal range, increased above 2 mg/dl, the case was considered an ARF. Treatment and outcome of patients that developed ARF were analyzed.

Eighty-five patients received IV acyclovir during the study period. Forty-one patients were included in the study. ARF developed in 8 out of 41 patients (19.5%). In the ARF cases, after beginning of treatment, the average time for increase of the serum creatinine levels was 4.2 days. Creatinine levels reached their peak in a mean time of 7.1 days (ranging from 3 to 14 days). Recovery of the renal function, evaluated by decrease of the creatinine level, varied from 1 to 7 days (mean of 3.6 days). ARF had a good outcome with hydration, lengthening of drug infusion time and adjustment of the drug dosage.

Acyclovir induced ARF in 19.5% of the patients. All patients had a positive response with return to a normal renal function after hydration, lengthening of drug infusion time and adjustment of the drug dosage. None of the patients required treatment with hemodialysis. Acyclovir is a safe drug when administered with certain preventive measures.