IgG4-positive Plasma Cells in Inflammatory Abdominal Aortic Aneurysm: The Possibility of an Aortic Manifestation of IgG4-related Sclerosing Disease

Abstract

Inflammatory abdominal aortic aneurysm (IAA) is associated with autoimmune disease. However, the precise mechanism of IAA remains unclear. There is increasing evidence that IgG4 is involved in the autoimmune mechanism of various idiopathic sclerosing lesions, including sclerosing pancreatitis and retroperitoneal fibrosis. The present study investigated the hypothesis that the IgG4-related autoimmune reaction is involved in the formation of IAA. The study group consisted of 11 cases of IAA (69.2 +/- 8.59y) and 12 age-matched cases of atherosclerotic abdominal aortic aneurysm (AAA, 69.6 +/- 5.94y), which were used in the previous report. A clinicopathologic examination of these lesions was performed, including histology and immunohistochemistry, in relation to the involvement of IgG4-positive plasma cells in the formation of IAA. No difference in the incidence of risk factors for atherosclerosis was observed between the patients with IAA and AAA. Autoimmune diseases were diagnosed in 2 patients with IAA, including rheumatoid arthritis and polyarteritis nodosa. A patient with IAA had pulmonary fibrosis. In contrast, autoimmune diseases were absent in patients with AAA. However, there was no significant difference in the incidence of autoimmune diseases between the patients with IAA and AAA. Lymphocyte and plasma cell infiltration and fibrosis were significantly more intense and extensive in IAA than in AAA. In addition, lymph follicle formation and vasculitis of small veins and arteries were frequently found in the affected lesions of IAA. Immunohistochemically, IAA showed a significant increase in the number of infiltrating IgG4-positive plasma cells and the incidence of a disrupted follicular dendritic cell network in lymph follicles, in comparison with AAA. These findings suggest that IAA may be an aortic lesion reflecting the presence of IgG4-related sclerosing disease, and not a simple inflammatory aneurysm of the aorta.

IgG4-related Inflammatory Abdominal Aortic Aneurysm, Spectrum of IgG4-related Chronic Periaortitis

“…28) There are no significant differences in the onset age, gender, or aneurysm diameter between these subtypes. 19,29) Many patients with IgG4-related IAAA had a medical history of allergy (food and drugs), allergic diseases (bronchial asthma, chronic bronchitis), and autoimmune diseases (rheumatism). 19,29) Complications of IgG4-SD in other organs (such as autoimmune pancreatitis and lymphadenitis) in IgG4-related IAAA have recently been reported.…”

“…19,29) Many patients with IgG4-related IAAA had a medical history of allergy (food and drugs), allergic diseases (bronchial asthma, chronic bronchitis), and autoimmune diseases (rheumatism). 19,29) Complications of IgG4-SD in other organs (such as autoimmune pancreatitis and lymphadenitis) in IgG4-related IAAA have recently been reported. 30,31) Needless to say, a high serum IgG4 level is the most important factor for the diagnosis of IgG4-related IAAA.…”

IgG4‐related systemic disease and lymphoplasmacytic aortitis

“…In many instances, "chronic periaortitis" has not been differentiated clearly from the atherosclerotic aneurysms that have the type of adventitial inflammation typical of atherosclerosis. Since 2008, a small number of cases of chronic periaortitis have been reported in association with IgG4-related systemic disease (15)(16)(17)(18).…”

Comparative Effectiveness of a Regional Virtual Tumor Board vs. Standard Care for Patients with Hepatocellular Cancer in a Regional Health Network

“…A study recently suggested that the autoimmune condition, IgG4-related sclerosing disease, may be associated with an increased risk for the development of IAAA [19]. However, there is limited evidence of an association between Sjögren's syndrome and IAAA in the literature.…”