A visual guide for emergency radiologists navigating the complexity of abdominal vasculitis: part 2 - the mimickers.

Part 2 of this pictorial essay focuses on conditions that mimic abdominal vasculitis, examining their distinct imaging characteristics using 2D and advanced 3D CT techniques, including volume rendering (VR) and cinematic rendering (CR). These mimickers include fibromuscular dysplasia (FMD), segmental arterial mediolysis (SAM), IgG4-related disease, median arcuate ligament syndrome, infections, genetic conditions such as vascular Ehlers-Danlos syndrome, Marfan syndrome, and Loeys-Dietz syndrome, as well as non-Langerhans cell histiocytic disorders like Erdheim-Chester disease and Rosai-Dorfman disease. This article features illustrative case examples that emphasize the imaging hallmarks of these conditions, aiding radiologists in differentiating them from true vasculitis. This is particularly useful in acute scenarios like abdominal pain, where timely recognition is crucial for informing treatment decisions and improving patient outcomes.