P3971 - Development of Autoimmune Hepatitis in a Patient With Mixed Connective Tissue Disease: A Rare Occurrence

Bryan Harper, DO, Joshua Scott, DO, Chris Casaccio, DO
United States Air Force, Wright Patterson Air Force Base, OH

Introduction: Autoimmune rheumatologic diseases often have multiple system complications with overlap of symptoms and features from different syndromes. Mixed Connective Tissue disease (MCTD) is a rheumatologic disease occurring by having features of 3 separate autoimmune diseases and high titer u-1-small nuclear ribonuclear protein. The most common gastrointestinal symptom is dysmotility occurring in 60-80%, due to overlap with systemic sclerosis. Hepatic involvement is rare, estimated at 8.8%, with primary biliary cholangitis as the most common hepatic manifestation. This case report will describe the rare occurrence of autoimmune hepatitis (AIH) in a patient on stable treatment for MCTD.

Case Description/Methods: The patient was a 55-year-old female who had been diagnosed with MCTD three years prior. Her disease was stable, treated with hydroxychloroquine and methotrexate. Routine monitoring of methotrexate administration revealed she had elevated aspartate aminotransferase (AST) 325 U/L and alanine aminotransferase (ALT) 276 U/L. Originally attributed to methotrexate and alcohol consumption; the medication was discontinued. Repeat testing at two months showed AST and ALT continued to rise, prompting further testing. Smooth Muscle Antibody was >1:640 and she was referred to gastroenterology.
On initial presentation the patient had no explicit symptoms of hepatitis such as jaundice, pain over her liver, appetite changes, fever, or additional gastrointestinal effects. She reported increasing fatigue and bleeding of chronic telangiectasias. Additional testing revealed an Immunoglobulin G (IgG) level of 2429 mg/dL, increasing her AIH diagnostic score to 6. A liver biopsy revealed histology consistent with AIH. At the time of diagnosis, her labs were Alkaline Phosphatase 126 U/L, AST 367.6 U/L, ALT 91 U/L, IgG 3019 mg/dL, and a normal Bilirubin. Treatment was initiated with prednisone with improvement in her symptoms and down trending in her liver associated enzymes and IgG level.

Discussion: Often when patients are diagnosed with AIH, they have symptoms of severe liver dysfunction and signs of liver failure. This patient never developed signs or symptoms of liver failure aside from fatigue and worsening telangiectasias which were originally due to MCTD. While MCTD is an overlap of several autoimmune diseases, AIH is very rarely reported in these individuals.


Disclosures:


Bryan Harper, DO, Joshua Scott, DO, Chris Casaccio, DO. P3971 - Development of Autoimmune Hepatitis in a Patient With Mixed Connective Tissue Disease: A Rare Occurrence, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.