Dr. Huynh Van Trung, Deputy Head of the Department of Gastroenterology, Endoscopy and Gastrointestinal Endoscopic Surgery Center, Tam Anh General Hospital, Ho Chi Minh City, stated that autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) are chronic liver diseases related to immune system disorders. These conditions usually occur independently; overlap cases, such as this patient's, are rare, and their overlapping characteristics make diagnosis and treatment difficult.

Ms. Lai experienced fatigue and severe nocturnal skin itching, and two years ago, she was diagnosed with autoimmune hepatitis. She received medical treatment, and her most recent tests showed improved liver enzyme levels AST and ALT, with her hepatocellular inflammation responding well to therapy. Recently, she reported increased fatigue and itching in her palms and soles, prompting her to return to Tam Anh General Hospital, Ho Chi Minh City, for a liver function check.

According to Dr. Trung, although Ms. Lai's liver enzyme levels improved in previous and current tests, her GGT levels (an enzyme primarily found in the liver and bile ducts) consistently remained high, indicating that this was not solely autoimmune hepatitis.

Specialized autoantibody tests combined with a liver biopsy revealed negative anti-mitochondrial antibody M2 (AMA-M2), while other specific autoantibodies, including anti-Sp100 and anti-PML, were positive. These indicators helped doctors diagnose the patient with primary biliary cholangitis. Additionally, the liver biopsy showed lymphocytic cholangitis, damage to small bile ducts in the liver, and mild liver fibrosis.

Doctors diagnosed the patient with an overlap syndrome between autoimmune hepatitis and primary biliary cholangitis. This condition involves the coexistence of two autoimmune diseases, where the immune system simultaneously attacks liver cells and small bile ducts in the liver.

Dr. Trung consults with Ms. Lai. _Photo: Tam Anh General Hospital_

Doctors adjusted the treatment regimen. Ms. Lai received a bile acid supplement to improve cholestasis and protect liver function, alongside her autoimmune hepatitis treatment. After three months, the patient's bile enzyme levels improved, with GGT and ALP decreasing from 400/350 U/L to 250/215 U/L, and her fatigue and skin itching subsided. The patient requires at least 6 months to one year of follow-up to monitor her response to primary biliary cholangitis treatment.

Autoimmune hepatitis primarily causes damage to liver cells, whereas primary biliary cholangitis gradually damages and destroys small bile ducts in the liver, leading to cholestasis.

Dr. Hoang Dinh Thanh, from the Department of Gastroenterology, Tam Anh General Hospital, Ho Chi Minh City, stated that the exact cause of immune system dysfunction leading to attacks on the body's own tissues and organs remains unclear. However, the condition may involve a complex interaction between genetic and environmental factors, such as infections, medications, or other agents.

According to Dr. Thanh, many patients with cholangitis have negative AMA results, leading to diagnostic challenges and a risk of missed diagnoses. Therefore, when clinical suspicion arises, doctors may combine specific autoantibody tests with liver biochemical markers, imaging, and liver biopsy to confirm the diagnosis.

Patients with autoimmune hepatitis require concurrent monitoring of both liver cell injury and cholestasis markers. If AST and ALT levels improve but GGT and ALP remain elevated or continue to rise over time, patients should inform their doctor for further evaluation.

Quyen Phan

* The patient's name has been changed.