Fibrosis and Inflammation Histology Scores Predict Disease Remission in Pediatric Autoimmune Hepatitis

Objectives: To evaluate histological evolution and identify predictive factors for remission in pediatric autoimmune hepatitis (AIH). Methods: Retrospective study of 40 children under immunosuppressive treatment (10 AIH type I, 7 AIH type II, 20 autoimmune sclerosing cholangitis (ASC) and 3 seronegative AIH) was performed. Histological fibrosis and inflammation scores were assessed on baseline (n=40) and follow up (n=19) biopsies. Clinical, biochemical and histological characteristics were analyzed to identify predictive factors for disease remission. Results: Duration of follow up was median 4 years (3 months-19 years) and interval between paired biopsies was 4 years (3 months-18 years). In the paired biopsies group (n=19), histological evolution showed significant (p ≤ 0.01) regression of fibrosis score (baseline: 3 to follow up: 1) and inflammation score (baseline: 3 to follow up: 2). In ASC subgroup (n=8), fibrosis score showed insignificant change between paired biopsies (baseline: 4 to follow up: 5) (p=0.88). Predictive factors for remission were (1) follow up fibrosis and inflammation scores (OR 1.71 and 5.42; p ≤ 0.05) and (2) the evolution of fibrosis and inflammation between paired biopsies (OR 2.82 and 3.14; p ≤ 0.05). Conclusions: Treatment induces regression of histological fibrosis and inflammation in AIH, except for ASC subtype. Histological evolution predicts disease remission and highlights the importance of performing follow up biopsies in children unresponsive to treatment.