Acute Hepatitis A-Induced Autoimmune Hepatitis: A Case Report

Introduction and objectives

Autoimmune hepatitis is a chronic immune-mediated inflammatory disease characterized by hypergammaglobulinemia, the presence of autoantibodies and histologically lymphoplasmacytic portal inflammation (interphase hepatitis).^1,2 Its pathogenesis is unknown and it occurs in 3% of cases associated with hepatitis A virus infection.^3,4

Materials and Patients

29-year-old woman with no relevant medical history. She presented with acute hepatitis due to virus A in February 2024 (symptomatic clinical pattern with jaundice), corroborated by serology (IgM + antibodies) remission with supportive treatment in April. In May, she presented a new jaundice event, general malaise, and asthenia, so she underwent evaluation. On examination, jaundice and hepatomegaly were observed. Laboratory studies: BT 23.5mg/dL, BD 19.9mg/dL, ALT 534U/L, AST 827U/L, FA 128U/L; suggestive of acute hepatocellular injury (R factor=14). Hepatobiliary ultrasound rules out the obstruction and reports a diffuse increase in echogenicity; Serology: IgM HAV non-reactive, IgG HAV+ (ruling out a prolonged course of hepatitis A). Consumption of drugs, alcohol, and infections by other viruses (B, C, E, Epstein Barr, and HIV) are ruled out. The measurement of serum globulins reports hypergammaglobulinemia (IgG x 1.6 ULN); in addition, increased levels of antinuclear antibodies (ANAs, dilution 1:80) are detected by Immunofluorescence (IF); histopathological report of liver biopsy: chronic interface hepatitis, portal lymphoplasmacytic infiltrate and lobular damage, (fibrosis: F2); meeting all suggested criteria for the diagnosis of autoimmune hepatitis defined by the International Autoimmune Hepatitis Group Criteria.⁵ Due to all of the above, it was decided to start treatment with parenteral steroid at a dose of 1 mg/kg/day (prednisone equivalent), with a good response to medical management, observing a gradual reduction in the levels of bilirubin, liver enzymes, and immunoglobulin G levels after the first 72 hours of medical treatment.

Results

Several triggers have been identified for the appearance of outbreaks of autoimmune hepatitis among them viral infections, which are reported in the literature. In rare cases, the hepatitis A virus can precede an outbreak of autoimmune hepatitis type 1. The treatment to induce immune remission is based on the administration of steroids, which usually guarantees a good response, as in the reported clinical case.

Conclusions

Hepatitis A virus infection is associated with altered immunotolerance with subsequent activation of lymphocytes and the production of specific antibodies that trigger molecular mimicry, which is directly involved in the pathophysiology of autoimmune hepatitis. Exposure to external factors is considered necessary to trigger the autoimmune reaction against hepatic structures.

Ethics statement: The procedures indicated above are under the General Health Law on Research in Human Beings regulations, as as well as the Declaration of Helsinki and subsequent amendments.

Conflict of interest statement: None.

Financing: Regional Hospital Lic. Adolfo López Mateos ISSSTE.