This case report describes a 73 year old lady with a known Hereditary Haemorrhagic Encephalopathy (HHT) who presented with confusion. She had several previous self-limiting episodes over 3 months. She had known hepatic arterio-venous (AV) malformations. A urinary tract infection was detected and thought to be the cause of her confusion. However despite targeted antibiotic treatment her neurological state worsened (GCS 10/15) and she developed hepatic asterixis. Hepatic encephalopathy was confirmed with diagnostic EEG and elevated ammonia 211umol/l (<40). Laxative treatment had transient improvement but she was unsuitable for hepatic AV embolisation or liver transplantation. Hepatic encephalopathy is a rare complication of HHT with less than 10 previous documented cases.