The reported incidence of hepatic disorders in individuals with inflammatory bowel disease varies from 5% to more than 90% (2-8). This incidence varies according to the means by which patients are selected and the criteria used for determining the presence of liver disease. For example, studies that use wedge liver biopsies at the time of laparotomy for inflammatory bowel disease tend to have the highest percentages of occurrence of hepatobiliary disease (2,3). If these biopsies are reviewed and individuals having only minor histological changes of the liver are excluded or only those individuals undergoing needle biopsy of the liver are considered, the incidence of such disease is significantly less (4-6). These observations may be attributed to, at least in part, the patchy histological distribution of some disorders of the liver. Furthermore, if the diagnosis of liver disease is based solely on clinical and laboratory information, the incidence of liver disease is only approximately 2% to 6% (7-9). Individuals having wedge biopsies at the time of bowel surgery are likely to be the most ill and are likely to suffer from the greatest extent of malnutrition, which may also affect the liver biopsies. An important observation of several studies of patients with significant liver disease documented by liver biopsy is that many of these patients had either lacked biochemical evidence of liver disease or had developed normal values of biochemical liver function tests subsequent to the performance of liver biopsy (3,5,6). This observation is supported by the fact that those individuals screened for liver disease solely by clinical and laboratory information represent the smallest group of patients with Crohn 's disease also having liver disease. Therefore, if only clinical and laboratory screening methods are used to detect liver disease, then the presence of significant liver disease in some patients with Crohn 's disease will be missed.