Non-specific interstitial pneumonia associated with clinically amyopathic dermatomyositis showing 'crazy paving' appearance on thin-section lung CT

The "crazy paving" appearance consists of ground-glass opacity superimposed on a network of linear opacities on thin-section computed tomography (CT) images of the lung. This finding has been described in a variety of diseases but is extremely rare in patients with non-specific interstitial pneumonia (NSIP). We describe a 45-year-old woman with biopsy-proven NSIP associated with clinically amyopathic dermatomyositis that showed a "crazy paving" appearance on thin-section CT of the lung. Clinicians should include NSIP in the differential diagnosis in patients presenting with "crazy paving" appearance on thin-section chest CT.