IgG4-related inflammatory abdominal aortic aneurysm.

Area of Science:

• Immunology
• Vascular Medicine
• Rheumatology

Background:

• IgG4-related systemic disease is a recently identified condition.
• It is characterized by elevated serum IgG4, specific inflammatory patterns, and multi-organ involvement.
• Some inflammatory abdominal aortic aneurysms (IAAA) share these clinicopathological features.

Purpose of the Study:

• To review the concept of IgG4-related IAAA.
• To highlight the clinicopathological similarities between IAAA and IgG4-related systemic disease.
• To discuss the implications for understanding and managing aortic lesions.

Main Methods:

• Literature review of IgG4-related systemic disease and IAAA.
• Analysis of clinicopathological features of reported IgG4-related IAAA cases.
• Synthesis of current understanding regarding IgG4-related vascular disease.

Main Results:

• IgG4-related IAAA exhibits high serum IgG4 and IgE, positive antinuclear antibodies, and a history of allergic disorders.
• Patients with IgG4-related IAAA are at risk for developing IgG4-related systemic disease in other organs.
• Histopathology reveals sclerosing inflammation with IgG4-positive plasmacytes, primarily in the adventitia, with similar findings in other large arteries.

Conclusions:

• Recognizing IgG4-related systemic disease in vascular lesions like IAAA may lead to new therapeutic approaches.
• The understanding of IgG4-related IAAA is nascent, with only a few years since its initial description.
• Further studies are essential to explore other IgG4-related vascular manifestations, the efficacy of steroid therapy for IgG4-IAAA, and its underlying pathology and immunology.