Nonspecific interstitial pneumonitis: a new anatomoclinical entity among idiopathic diffuse interstitial pneumonias

Nonspecific intersitial pneumonitis with fibrosis has been individualized w ithin the group of idiopathic diffuse interstitial pneumonias by pathologic al criteria. It is differentiated from usual interstitial pneumonitis by! t he temporal uniformity; of the lesions, a prominent inflammatory interstiti al infiltration, and the absence of honeycombing. Clinical and functional s ymptoms are those of diffuse interstitial pneumonitis. An etiology may be f ound in about half the cases, including connective tissue disease, exposure to organic antigens, or recent acute lung injury. Compound tomography of t he chest shows bilateral ground glass opacities, and alveolar opacities wit h a peribronchiolar of patchy distribution. Prognosis is rather good since a majority of patients improve when treated with corticosteroids or with an association of corticosteroids and immunosuppressive drugs. These etiologi c and prognostic features justify the individualization of nonspecific inte rstitial pneumonitis with fibrosis as a distinct clinicopathological entity .