Valacyclovir-associated neurotoxicity treated with intensification of peritoneal dialysis

We report a 57-year-old woman with end-stage renal disease (ESRD) on maintenance peritoneal dialysis (PD), who presented to the emergency room (ER) by ambulance with complaints of confusion and altered sensorium for 48 hours. She had been reviewed in a walk-in clinic 72 hours earlier and had been prescribed the standard 1000 mg three times per day of valacyclovir for an acute attack of shingles instead of 500 mg once a day on ESRD. In the ER, she received further 500 mg of intravenous acyclovir as herpes encephalitis was clinically suspected. CT of the brain and lumbar puncture were non-contributory to the diagnosis. Valacyclovir and acyclovir were discontinued when the diagnosis of valacyclovir-associated neurotoxicity became clinically evident. As the patient's Glasgow Coma Scale declined, we intensified her PD regimen from one to six exchanges per day and 24 hours later there was a significant neurological improvement.