Acute exacerbation of idiopathic pulmonary fibrosis: report of a series.

This study describes five cases presenting an acute clinical course of pulmonary fibrosis, in the absence of specific precipitating factors. A retrospective chart review of five patients with histologically proved usual interstitial pneumonia was carried out in 2001-2002. Clinical data, bronchoalveolar lavage (BAL) findings, high resolution computed tomography and histological features were reported. On admission all cases presented hypoxemia and dyspnoea, while some showed an increase of carbohydrate antigen 19.9 or laboratory tests typical of infection, although appropriate cultures were all negative. Altogether, four subjects died and only one is on follow-up. A pattern of diffuse ground-glass or alveolar opacification superimposed on reticular and linear findings was evident on lung imaging in all cases. Marked neutrophilia, together with type II reactive cells hyperplasia, was detected on BAL. Histological findings, from open lung biopsy or autopsy, showed all the aspects of usual interstitial pneumonia with superimposed features of acute lung injury, such as diffuse alveolar damage, with or without hyaline membranes, type II reactive cells hyperplasia and numerous fibroblastic foci. This study also underlines the diagnostic value of bronchoalveolar lavage versus open lung biopsy.