Interstitial disease associated with connective tissue disease and vasculitis.

Systemic autoimmune diseases comprise a complex, heterogeneous group of entities. Noteworthy among the pulmonary complications of these entities is interstitial involvement, which manifests with the same radiopathologic patterns as in idiopathic interstitial pneumonia. High-resolution computed tomography is the gold-standard imaging technique; it enables us to identify and classify the disease and to determine its extent, providing useful information about the prognosis. In this group of processes, the most common pattern of presentation is nonspecific interstitial pneumonia. It is essential for radiologists to work together in collaboration with other specialists to reach the correct diagnosis and enable appropriate, integrated treatment.