Editor,—A 23 year old man was referred to the outpatient clinic in view of persistently abnormal liver function tests for five years. In 1992, he had a gastrointestinal illness manifest by abdominal pain, diarrhoea and vomiting which lasted intermittently for one month. At that time, investigations by his general practitioner revealed that his liver function tests were abnormal: alkaline phosphatase (ALP) 408 U/l, aspartate aminotransferase (AST) 383 IU/l, alanine aminotransferase (ALT) 922 U/l, γ-glutamyl transferase (GGT) 147 IU/l. Viral serology for hepatitis A and B and a Paul–Bunnell test were negative. His symptoms resolved, but his liver function tests did not return to normal.

He was referred to the medical outpatient clinic in 1997 because of the development of further symptoms: episodic abdominal pain, diarrhoea, itch, and fatigue. His urine was noted to be dark and his faeces was pale. Alcohol consumption …