title: Acute exacerbation of chronic interstitial pneumonia: high-resolution computed tomography and pathologic findings.
abstract: OBJECTIVE
  To review the high-resolution computed tomography (CT) and histologic findings of acute exacerbation of chronic interstitial pneumonia and to assess the potential value of CT and histologic findings in predicting prognosis.
  
  
  METHODS
  The study included 24 patients with clinical and histologic diagnosis of acute exacerbation of chronic interstitial pneumonia who underwent CT within 1 month before biopsy or autopsy. The final diagnosis was acute exacerbation of idiopathic pulmonary fibrosis (n=12), usual interstitial pneumonia associated with connective tissue disorders (n=5), idiopathic nonspecific interstitial pneumonia (n=4), and nonspecific interstitial pneumonia associated with connective tissue disorders (n=3).
  
  
  RESULTS
  The main CT findings consisted of bilateral ground-glass opacities (100%) and consolidation (71%) superimposed on a reticular pattern. The ground-glass opacities and/or consolidation were diffuse in 54% of the cases, multifocal in 21%, and peripheral in 25%. The histologic patterns of acute injury consisted of diffuse alveolar damage (n=20), acute organizing pneumonia (OP) (n=3), and extensive fibroblastic foci (n=1). Eight (33%) patients survived the acute episode, including all 3 patients with OP and the patient with extensive fibroblastic foci (P=0.01). The survivors included 3 of 13 (23%) patients with diffuse parenchymal opacification, 2 of 5 (40%) patients with multifocal, and 3 of 6 (50%) patients with peripheral opacification on CT.
  
  
  CONCLUSIONS
  The CT findings of acute exacerbation of chronic interstitial pneumonia consist of diffuse, multifocal, or peripheral parenchymal opacification superimposed on reticulation. Histologic findings of OP are superior to CT in predicting prognosis.
authors.affiliation: Department of Radiology, Vancouver General Hospital and University of British Columbia, Vancouver, BC, Canada. isabela.silva@vch.ca
authors.forename: C Isabela S
authors.initials: CI
authors.lastname: Silva
authors.forename: Nestor L
authors.initials: NL
authors.lastname: Müller
authors.forename: Kiminori
authors.initials: K
authors.lastname: Fujimoto
authors.forename: Seiya
authors.initials: S
authors.lastname: Kato
authors.forename: Kazuya
authors.initials: K
authors.lastname: Ichikado
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Taniguchi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kondoh
authors.forename: Takeshi
authors.initials: T
authors.lastname: Johkoh
authors.forename: Andrew
authors.initials: A
authors.lastname: Churg
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D005260:Female; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D014057:Tomography, X-Ray Computed / Q000379:methods*