In spite of intense diagnostic testing, no cause for the chronically aggressive hepatitis of a 48-year old male patient was found. Evidence for an autoimmune process, however, could be derived from a high titer of pANCA. Only according to the revised criteria of the working group on autoimmune hepatitis, but not to the first version, it was possible to classify this as an autoimmune hepatitis. Despite of high-dose steroid treatment and accelerated preparation for liver transplantation the patient died of the complications of rapid liver failure. Thus, in case of unclear rapid progressive hepatitis, the revised criteria of autoimmune hepatitis should be reviewed early and with high priority and consequent high-dose steroid therapy and preparation for liver transplantation should be initiated. The prognostic impact of a high titer of pANCA in patients with autoimmune hepatitis remains to be established.