Useful in the diagnosis of autoimmune hepatitis (AIH). Soluble liver antigen (SLA) antibodies have been found in patients with type 3 AIH in which the conventional serological markers of AIH (i.e., antinuclear antibody, antismooth muscle antibody, anti-LKM-1 antibody) are absent. SLA testing may aid in establishing a diagnosis of AIH, preventing treatment delay. Definitive diagnosis should be based on the correlation of all available clinical, biochemical, and liver biopsy information.