Immunoglobulin G4–Related Periaortitis Complicated by Aortic Rupture and Aortoduodenal Fistula After Endovascular AAA Repair

PURPOSE: To report a rare and complicated case of immunoglobulin (Ig) G4-related periaortitis involving both the aortic wall and the retroperitoneum without aneurysmal formation. CASE REPORT: A 79-year-old man with IgG4-related periaortitis suffered aortic rupture despite a normal caliber aorta after 6 months of steroid therapy (20 mg/d). Endovascular repair with an aortic cuff sealed the rupture. Steroid therapy was halted 2 weeks later due to infection. Four months later, a biopsy during esophagogastroduodenoscopy to investigate gastrointestinal bleeding suggested a relapse of IgG4-RD in the duodenum. Subsequent aortoduodenal fistula formation proved fatal. Generally, IgG4-related periaortitis does not result in such complications due to the absence of aneurysm formation and a thick aortic wall. CONCLUSIONS: Our report highlights a rare case of IgG4-related periaortitis where complications resulted following steroid therapy and surgical intervention, emphasizing the difficulties in dealing with IgG4-related cardiovascular lesions.