[Acute renal failure following a treatment with acyclovir].

UNLABELLED: The antiviral molecule acyclovir can be responsible of severe renal dysfunction. Intratubular crystal precipitation of the drug may represent a major pathogenetic mechanism.

OBSERVATION: A 30-year old, immunocompetent woman was admitted in the neurology unit for a viral meningo-encephalitic syndrome. Intravenous acyclovir was delivered at the dose of 45 mg/kg per day. Despite a neurological improvement, she developed an acute renal insufficiency with the serum creatinine increasing from 63 to 385 micromol/L within 12 days. The urine study revealed great amounts of birefringent crystals which were typical of acyclovir derived crystals according to the spectrophotometric examination. Withdrawal of acyclovir treatment in combination with oral and parenteral hydration resulted in a complete recovery of the renal function. The conditions favouring acyclovir-induced nephrotoxicity are discussed.