Posttransplant immune hepatitis in pediatric liver transplant recipients : Incidence and maintenance therapy with azathioprine

Cases of so-called autoimmune hepatitis (AH) have been reported after liver transplantation. Our aim was to evaluate the incidence in a series of 471 pediatric liver transplant recipients. Between 1984 and 1998, 471 children had orthotopic liver transplantation (OLT). Children are followed up on a regular basis, with full clinical, biochemical, and histologic evaluation at 6 months, 1, 2, 5, 7, and 10 years after OLT. Children with unexplained abnormal liver tests were screened for autoimmune markers (total gamma-globulins, smooth muscle antibodies [SMA], liver kidney microsome antibodies [LKM], antinuclear factor [ANA]). From January of 1998 until December of 1998, autoimmune markers were prospectively searched in all children admitted for regular posttransplant follow-up (n = 118). Eleven of 471 children (2.35%) were found with autoimmune hepatitis, 9 retrospectively and 2 prospectively. None had previous autoimmune liver disease. Patients had a history of steroid-dependent hepatitis. Histology showed variable degree of portal and lobular inflammation, piecemeal necrosis, and bridging collapse. Mean (+/-SDS) aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities at diagnosis were 173+/-145 and 196+/-157 IU/L, respectively (nl