Background: Epithelioid granulomas have been reported in 2-15% of unselected liver biopsies, with numerous underlying aetiologies described. However, all UK series were reported before identification of hepatitis C virus (HCV).
Aim: To evaluate the current aetiologies of hepatic granulomas and to assess the prognosis for the "idiopathic" group, in which all investigations for a recognised cause were negative or normal.
Methods: A retrospective review of patient case notes between 1991 and 2001; all patients who had a liver biopsy at Glasgow Royal Infirmary revealing epithelioid granulomas had their case notes and liver biopsies reviewed and a standard proforma completed.
Results: Over the study period, 1662 liver biopsies were performed. Hepatic granulomas were found in 63. Of those identified, 47 were female, with a mean age of 42 years (range, 17-81). Underlying aetiologies were as follows: primary biliary cirrhosis (PBC; 23.8%), sarcoidosis (11.1%), idiopathic (11.1%), drug induced (9.5%), HCV (9.5%), PBC/autoimmune hepatitis (AIH) overlap (6.3%), Hodgkin lymphoma (6.3%), AIH (4.8%), tuberculosis (4.8%), resolving biliary obstruction (3.2%), and other single miscellaneous causes (9.5%). Of the seven patients with idiopathic hepatic granulomas, one was lost to follow up, one died of stroke, and the remaining five were well with no liver related morbidity at a mean follow up of 6.2 years.
Conclusions: The aetiology of hepatic granulomas is broad ranging, with HCV an important cause in this population. Despite extensive investigations, a 10-15% of patients still had "idiopathic" hepatic granulomas. However, the prognosis for this last group appears to be excellent.