Arterial Microaneurysms in Polyarteritis Nodosa: Pathophysiology, Clinical Insights, and Management
Introduction Polyarteritis Nodosa (PAN) is a rare systemic necrotizing vasculitis that predominantly affects medium- and small-sized arteries, leading to microaneurysm formation, ischemia, and multiorgan dysfunction. Among its hallmark imaging findings, arterial microaneurysms remain a critical diagnostic clue, particularly in abdominal visceral arteries. The recognition of this feature is vital for early diagnosis, differentiation from other vasculitides, and guiding effective treatment. This article provides a comprehensive expert-level review of arterial microaneurysms in PAN, integrating the latest evidence-based literature, imaging features, treatment strategies, and prognosis. Additionally, illustrative figures from the attached case report are included, with descriptive captions, and a quiz section is provided for medical education purposes. Pathophysiology The pathogenesis of arterial microaneurysms in PAN involves immune-mediated necrotizing inflammation of me...