Pathologic manifestations of bronchiolitis, constrictive bronchiolitis, cryptogenic organizing pneumonia, and diffuse panbronchiolitis.

This article reviews the histopathological findings in a variety of inflammatory bronchiolar diseases. The emphasis is on differentiating syndromes of idiopathic airflow limitation (constrictive bronchiolitis and diffuse panbronchiolitis) from cryptogenic organizing pneumonia (idiopathic bronchiolitis obliterans organizing pneumonia). The histopathological findings in each of these conditions are relatively nonspecific; therefore, it is imperative that pathological findings are correlated with clinical and roentgenographic information before a specific diagnosis is made.