"Overlap" Syndromes in Autoimmune Liver Disease: Definitions, Clinical Challenges and Future Directions

Area of Science:

• Hepatology
• Immunology
• Internal Medicine

Background:

• Autoimmune liver diseases (AILDs) encompass autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis.
• These conditions are characterized by immune-mediated liver injury but can present as overlapping or variant syndromes.
• Current understanding of pathophysiology and rarity hinder standardized definitions and evidence-based treatment protocols.

Purpose of the Study:

• To provide a pragmatic clinical approach for managing autoimmune liver disease overlap and variant syndromes.
• To address the challenges posed by the spectrum of AILDs and their complex presentations.

Main Methods:

• Literature review focusing on the spectrum of autoimmune liver diseases.
• Analysis of clinical presentations and pathophysiological pathways of AILD variants.
• Synthesis of existing evidence to propose a practical management strategy.

Main Results:

• Autoimmune liver diseases represent a spectrum rather than distinct entities.
• Overlap and variant syndromes are phenotypic variations of shared immune pathways.
• A pragmatic approach is needed due to lack of standardized definitions and evidence-based protocols.

Conclusions:

• Recognizing AILDs on a continuum is crucial for accurate diagnosis and management.
• Further research into shared pathophysiological mechanisms is warranted.
• A practical clinical framework can improve care for patients with complex AILD presentations.