Clinical characteristics and outcomes of 61 patients with chronic periaortitis including IgG4-related and non-IgG4-related cases.

Objective: Chronic periaortitis (CP) is a disease characterized by a fibro-inflammatory periaortic cuff and adventitia-predominant fibrosis. CP encompasses idiopathic retroperitoneal fibrosis and inflammatory abdominal aortic aneurysm (AAA), and recent studies have documented overlap between CP and immunoglobulin G4-related disease (IgG4-RD). This study aimed to investigate clinical characteristics and treatment outcomes of patients with CP.

Methods: CP patients were identified by retrospective review of 1245 patients with International Classification of Diseases 10th edition code of aortitis or aortic disease. Patients were further classified into IgG4-related and non-IgG4-related CP according to the criteria proposed by a Japanese study.

Results: A total of 61 CP patients were identified. Patients showed a male predominance (70%) with median age of 61 at diagnosis. The abdominal aorta was most commonly involved (84%), while the thoracic aorta was affected in 46% of patients. Twenty-three (38%) patients had accompanying aortic aneurysm. Approximately 60% of patients achieved remission without further relapse during the course. Ten patients were classified as IgG4-related and 25 as non-IgG4-related. There was no significant difference in clinical features and outcomes between groups, with the exception of older age and greater pancreas involvement in IgG4-related patients.

Conclusions: We documented 61 CP patients including 10 IgG4-related cases. CP involved the abdominal aorta in most patients and the thoracic aorta in approximately 50% of patients. IgG4-related CP patients were older and had greater pancreas involvement, but disease outcomes appeared to be similar between IgG4-related and non-IgG4-related CP.