HEALTHCARE professionals in the U.S. are closely watching progress in the diagnosis and management of IgG4-related periaortitis, periarteritis, and retroperitoneal fibrosis, a complex subset of IgG4-related disease (IgG4-RD) that mimics other conditions and defies simple diagnostic approaches. A new study offers critical updates that may enhance clinical decision-making and improve patient outcomes.
IgG4-RD is a systemic, immune-mediated inflammatory disorder that can affect various organs. When it targets large vessels like the aorta and surrounding tissues, standard diagnostic tools often fall short. Biopsies are hard to obtain in vascular locations, and the presentation often overlaps with other fibrotic or inflammatory diseases.
In this updated review, researchers examined 209 patients diagnosed with IgG4-related periaortitis (PAo), periarteritis (PA), and retroperitoneal fibrosis (RPF). Organ-specific criteria were developed using expert-confirmed diagnoses and later validated against a group of patients with similar but unrelated conditions.
The results showed that traditional histopathological markers, like storiform fibrosis and obliterative phlebitis, were present in 71.4% of biopsied cases. Radiographic imaging and elevated serum IgG4 levels proved essential, particularly when biopsy wasn’t feasible. Notably, the new criteria boosted diagnostic sensitivity from 68.4% to 77.2%, with only a slight drop in specificity.
This means clinicians can more confidently identify and manage IgG4-related arterial disease without relying solely on tissue samples. Importantly, the study emphasizes that even with classification systems like those developed by ACR and EULAR, diagnosis of PAo, PA, and RPF remains more complex than IgG4 involvement of salivary glands, pancreas, or kidneys.
These findings underscore the need for organ-specific diagnostic tools and personalized treatment strategies to address the unique challenges of vascular involvement in IgG4-RD. As research continues, radiologists, rheumatologists, and immunologists alike will benefit from these targeted diagnostic improvements.
Reference: Kawano M. Update on IgG4-related periaortitis/retroperitoneal fibrosis and periarteritis -recent clinical, diagnostic and therapeutic advances. Semin Arthritis Rheum. 2025:152691. [Epub ahead of print].
