The patient must meet the criteria for both AIH and PBC.
Criteria for AIH - at least 2 of the following:
(1) serum ALT > 5 times the upper limit of the normal reference range
(2) one or both of the following:
(2a) serum IgG levels > 2 times the upper limit of the normal reference range
(2b) presence of antibodies to smooth muscle
(3) one or both of the following seen on liver biopsy:
(3a) moderate to severe periportal lymphocytic piecemeal necrosis
(3b) moderate to severe periseptal lymphocytic piecemeal necrosis
Criteria for PBC - at least 2 of the following:
(1) one or both of the following:
(1a) serum alkaline phosphatase levels > 2 times the upper limit of the normal reference range
(1b) serum GGT > 5 times the upper limit of the normal reference range
(2) presence of antimitochondrial antibodies (AMA)
(3) florid bile duct lesions seen on liver biopsy