The CT shows subpleural and patchy, bilateral lower lung zone opacities with ground-glass and irregular lines. Contrast this CT with that of UIP . In a study of 7 patients with biopsy confirmed, untreated NSIP, radiographs showed patchy, bilateral opacities involving the mid and lower lung zones preferentially. There are increased numbers of alveolar macrophages.
Fibrosis is minimal.
However, the major pattern was an interstitial pneumonia with little airspace organization. The disease usually responds to steroids. Katzenstein A-L, Myers J. Idiopathic pulmonary fibrosis. Clinical relevance of pathologic classification. Bjoraker J, Ryu J, Edwin M, Myers J, Tazelaar H, Schroeder D, Offord K. Prognostic significance of histopathologic subsets in idiopathic pulmonary fibrosis.