Abstract
Systemic primary vasculitides are rare idiopathic diseases causing an inflammatory injury to the vessel walls. A pulmonary involvement is frequent, and chest-CT is the imaging technique of reference in its assessment. An extremely wide variety of parenchymal, vascular and airways abnormalities, has been described and diagnosis can be challenging: knowledge of clinical data and a close cooperation with the referring physician is often crucial. The aim of this work is to describe the most common typical and atypical CT features of pulmonary vasculitis and their possible changes over time and therapy, focusing on the differential diagnosis with other inflammatory/infectious or neoplastic diseases.