A 41-year-old man with a previous kidney transplant was referred for arterial hypertension and acute renal failure. Initial neurological examination was normal. Laboratory data showed a high serum cyclosporine A concentration. A few hours later, he developed generalised tonic-clonic seizures. The brain computed tomogram was not remarkable, but Glasgow Coma Scale score remained at 8. Mechanical ventilation was required for rapidly progressive hypoxaemia related to Staphylococcus aureus pneumonia and septicaemia. Noradrenaline infusion was needed for only nine hours, with no major drop in mean arterial blood pressure. On day three his Glasgow Coma Scale score was 3/15, with fixed dilated pupils. The brain computed tomogram revealed bilateral hypodense lesions in the posterior areas together with cerebral oedema and the patient was subsequently declared brain dead. We discuss the possibility of a posterior reversible encephalopathy syndrome, likely triggered by a gram-positive septicaemia in addition to other risk factors.