Republished: recent advances in autoimmune pancreatitis: type 1 and type 2

Area of Science:

• Gastroenterology
• Immunology
• Pathology

Background:

• Autoimmune pancreatitis (AIP) is a chronic pancreatitis with distinct clinical, histological, and therapeutic features.
• AIP is sub-classified into Type 1 and Type 2, with international consensus criteria aiding diagnosis.
• Type 1 AIP is associated with IgG4-related disease, while Type 2 is pancreas-specific.

Purpose of the Study:

• To review the current understanding of autoimmune pancreatitis (AIP), including its subtypes, diagnosis, and management.
• To discuss the role of IgG4 in Type 1 AIP and the therapeutic strategies for both subtypes.
• To highlight areas for future research in AIP pathogenesis and treatment.

Main Methods:

• Review of existing literature and international consensus criteria for autoimmune pancreatitis (AIP).
• Analysis of clinical, histological, and therapeutic characteristics of Type 1 and Type 2 AIP.
• Evaluation of the proposed role of IgG4 and the efficacy of steroid therapy and other treatments.

Main Results:

• Type 1 AIP, a manifestation of IgG4-related disease, presents with obstructive jaundice and responds to steroids, though relapses are common and may require long-term management.
• Type 2 AIP is a pancreas-specific disorder, also responsive to steroids, with less frequent relapses and is not associated with IgG4.
• While IgG4 is associated with Type 1 AIP, its direct pathogenic role is unlikely; steroid therapy is the cornerstone of treatment for both types.

Conclusions:

• Autoimmune pancreatitis (AIP) encompasses two distinct subtypes requiring tailored management approaches.
• Steroid therapy is effective for both Type 1 and Type 2 AIP, with ongoing research into optimizing long-term treatment and remission maintenance.
• Further studies are needed to elucidate the pathogenesis of AIP and establish definitive treatment guidelines, particularly for relapsing Type 1 AIP.