We describe a 12-year-old girl with an early onset neurologic disease of slow progressiveness and electro-encephalography showing epileptic activity. The girl developed fulminant liver failure 5 months after the start of valproic acid treatment. Repeated mitochondrial assays failed to prove a mitochondrial disorder, but muscle biopsies were slightly pathological. Liver histology indicated acute-on-chronic liver disease. Six weeks after a successful orthotopic liver transplantation her neurological condition deteriorated rapidly, soon leading to generalized cortical disease and death. Post-mortem brain examination showed advanced central nervous destruction. We suggest that this is a late-onset Huttenlocher variant of Alpers' syndrome, where fulminant liver failure can be triggered by valproic acid, and orthotopic liver transplantation can subsequently trigger a fatal neurologic deterioration. Our case illustrates that when a referral center receives a previously unknown patient with hepatocellular insufficiency, it might be impossible to differentiate between fulminant vs. acute-on-chronic liver failure, and the decision whether to perform a liver transplantation or not would become difficult.