Frequency and significance of antibodies to soluble liver antigen/liver pancreas in variant autoimmune hepatitis

Background: Antibodies to soluble liver antigen/liver pancreas are highly specific markers of autoimmune hepatitis. Aims: Determine the frequency and clinical significance of these antibodies in the variant syndromes. Methods: Antibodies to soluble liver antigen/liver pancreas were determined in 28 patients with variant forms, including 10 with cryptogenic chronic hepatitis and 18 with cholestatic variants. One hundred and seventy-two patients with classical autoimmune hepatitis were similarly tested. Results: Seven of the 28 patients with variant forms had the antibodies, and this frequency was not statistically different than that in classical disease (25 vs. 12%, p = 0.08). Antibodies were most common in patients with cryptogenic chronic hepatitis (40%). Seropositive patients were indistinguishable from seronegative patients with variant forms, and they responded as well to corticosteroid therapy as patients with autoimmune hepatitis. Relapse after corticosteroid withdrawal invariably occurred in the seropositive patients whether with variant or classical disease, and HLA DR3 was more common in the seropositive patients with variant forms than in normal subjects (60 vs. 15%, p = 0.03). Conclusions: Antibodies to soluble liver antigen/liver pancreas occur commonly in the variant forms of autoimmune hepatitis and identify patients that closely resemble classical disease. Seropositivity is associated with relapse after corticosteroid withdrawal and HLA DR3. The antibodies may be surrogate markers of a genetic propensity to relapse that is independent of clinical phenotype.