Acute interstitial pneumonia: comparison of high-resolution computed tomography findings between survivors and nonsurvivors.

This study compared high-resolution computed tomography (CT) findings between 10 survivors and 21 nonsurvivors of acute interstitial pneumonia and evaluated whether the CT findings were predictive of patients' response to treatment. The survivor and nonsurvivor groups with pathologically or clinically diagnosed acute interstitial pneumonia were similar in age, sex, disease duration, and lung injury score. Retrospective, subjective evaluations of the CT scans were conducted by two independent observers without knowledge of patient outcomes. CT findings were graded on a one to six scale corresponding to consecutive pathologic phases as follows: areas of (1) normal attenuation, (2) ground-glass attenuation, (3) consolidation, (4) ground-glass attenuation associated with traction bronchiolectasis or bronchiectasis, (5) consolidation associated with traction bronchiolectasis or bronchiectasis, and (6) honeycombing. An overall score was obtained by quantifying the extent of each abnormality in three lung zones in each lung. The extent of ground-glass attenuation or consolidation associated with traction bronchiolectasis or bronchiectasis was less in survivors than nonsurvivors (p = 0.004 and p = 0.009, respectively). Architectural distortion was less frequent, and ground-glass attenuation or consolidation without traction bronchiolectasis or bronchiectasis was more extensive in survivors than in nonsurvivors (p = 0.007, p = 0.002, and p = 0.029, respectively). Overall CT scores of survivors were significantly lower than those of nonsurvivors (p = 0.0003). A CT score of less than 245 had an 80% positive and a 90% negative predictive value for survival. There was good interobserver agreement in the assessment of the CT findings (Kappa 0.75). The results indicate that CT assessment is potentially helpful in predicting patient prognosis in acute interstitial pneumonia regardless of the degree of physiologic abnormality.