[An autopsy case of adult respiratory distress syndrome (ARDS) with peculiar histopathological features modified by a positive end-expiratory pressure (PEEP) therapy].

A case is reported of adult respiratory distress syndrome(ARDS) combined with barotrauma due to positive end-expiratory pressure (PEEP) therapy. The patient was a 32-year-old woman with fulminant hepatitis, type B, who died of ARDS 22 days after the onset of the illness. The autopsy revealed extraordinary heavy lungs (left: 923g, right: 985g) with edema in the peripheral part and marked emphysematous changes in the central part near the hili. Histologically, scattered foci of intra-alveolar organization and interstitial fibrosis with hemorrhage were observed, which might have been the result of the proceeding pneumonia. The emphysematous lesion seen in this case was peculiar and not like any type of of ordinary pulmonary emphysema. Judging from the strange, sharply demarcated emphysematous lesion with marked destruction of alveolar structure, and the good preservation of the alveolar structure in the edematous lesion, the emphysematous lesion might be barotrauma which was induced by PEEP therapy on top of pneumonia.