Autoimmune hepatitis--approach to diagnosis.

CONTEXT: Autoimmune hepatitis has diverse features that can delay its diagnosis and the institution of potentially lifesaving corticosteroid therapy.
OBJECTIVE: Review the clinical, laboratory, and histologic features of autoimmune hepatitis and promulgate routine application of its codified diagnostic criteria. DATA SOURCES: Reference lists and MEDLINE. STUDY SELECTION: All clinically pertinent published observations that indicate the diversity of manifestations and pitfalls in diagnosis. DATA EXTRACTION: Findings that had common clinical relevance and the potential to confuse the diagnosis or delay institution of therapy were selected. DATA SYNTHESIS: Autoimmune hepatitis can present acutely and have histologic features of centrilobular zone 3 inflammation. Many patients may be asymptomatic, but they frequently have severe or advanced disease and typically develop symptoms later. Autoantibodies are reflective of immune-mediated mechanisms, but they are not diagnostic, pathogenic, or even required for the diagnosis. Genetic factors affect susceptibility, clinical phenotype, and treatment outcome, and they may be clues to indigenous etiologic agents. Autoimmune hepatitis can recur or develop de novo after liver transplantation, and it should be considered in all transplanted patients with allograft dysfunction. Diagnostic criteria have been codified, and a scoring system quantifies the strength of the diagnosis and accommodates atypical or deficient features.
CONCLUSION: Autoimmune hepatitis is an important diagnosis to consider in all patients with chronic hepatitis of undetermined cause.