Large vessel involvement by IgG4-related disease

Area of Science:

• Rheumatology and Immunology
• Cardiovascular Medicine
• Radiology

Background:

• Immunoglobulin G4-related disease (IgG4-RD) is a fibroinflammatory condition affecting multiple organs.
• Vascular involvement in IgG4-RD, including aortitis and periaortitis, requires further characterization.
• Distinguishing primary IgG4-RD vasculitis from secondary vascular involvement is crucial.

Purpose of the Study:

• To describe the clinical features, radiological findings, and treatment response of IgG4-RD affecting large blood vessels.
• To differentiate between primary IgG4-related vasculitis and secondary vascular involvement.
• To assess the efficacy of B cell depletion therapy in these patients.

Main Methods:

• Retrospective review of clinical records and radiological studies of 160 IgG4-RD patients.
• Identification of 36 patients with large blood vessel involvement.
• Classification of vascular involvement as primary (inflammation of the vessel wall) or secondary (adjacent inflammation).

Main Results:

• 22.5% of IgG4-RD patients (36/160) had large-vessel involvement.
• Primary IgG4-related vasculitis most commonly presented as aortitis with aneurysm formation (13 patients).
• Secondary periaortitis due to retroperitoneal fibrosis was the most common secondary manifestation (27/29 patients).

Conclusions:

• IgG4-RD is a treatable cause of large-vessel vasculitis, presenting as primary aortitis or secondary periaortitis.
• Aortitis with aneurysm formation is the most common primary vascular manifestation.
• B cell depletion therapy, such as rituximab, shows positive treatment response for both primary and secondary vascular involvement.