Abdominal aorta (A, B) and retroperitoneum (C, D). A: At low magnification, inflammatory cell infiltrates are seen, and they form a so-called “aortitis” pattern. B: At high magnification, plasma cell and eosinophil infiltrates are seen in the adventitia. C-D: In the retroperitoneum, plasma cell and eosinophil infiltrates are seen around (C, D) and within (D, arrowheads) the peri-aortic nerve ganglions.
Fujii et al. Diagnostic Pathology 2014 9:41 doi:10.1186/1746-1596-9-41