Immunoglobulin G4–related coronary periarteritis: a systematic literature review with a case series

We aimed to assess the clinical and radiological characteristics of immunoglobulin G4-related coronary periarteritis through a systematic literature review and from our case series. In the systematic literature review, we assessed English language manuscripts on immunoglobulin G4-related coronary periarteritis cases. Additionally, we identified patients with immunoglobulin G4-related coronary periarteritis at St. Luke's International Hospital in Tokyo, Japan, from 2014 to 2020. We summarized patients' demographics, immunoglobulin-G and -G4 titers, site and morphological features of the coronary lesion, and other organ involvements. We identified 38 cases from the literature and four patients from our institute. Coronary lesions were detected using coronary computed tomography in 40 (95.2%) patients. Mass-like or diffuse wall-thickening lesion was the most frequently observed type in 33 (78.6%) patients. No trends at the site of the coronary arteries were identified. Overall, 32 (76.1%) patients had multiple-organ involvement, of which the most common lesion was peri-aortitis in 21 (50.0%) patients. Ten (23.8%) patients with an isolated coronary lesion had significantly lower immunoglobulin-G4 titers than those with other organ involvements (immunoglobulin-G4: 261 [161.0, 564.0] vs. 1355.0 [320.8, 2480.0] mg/dL, p = 0.033). The wall-thickening lesions responded well to immunosuppressive treatments. Mass-like or diffuse wall-thickening on coronary computed tomography is a characteristic radiographic finding of immunoglobulin G4-related coronary periarteritis, which can occur in any branch. Immunoglobulin G4-related coronary periarteritis showed similar characteristics to other organ lesions, including its relatively low serum immunoglobulin-G4 level in patients with a single-organ disease and its high responsiveness to glucocorticoids.