Bronchiolitis with airflow obstruction

Bronchiolar lesions are becoming increasingly recognized as an important cause of airflow obstruction. For this reason, it is helpful to have an update of the current clinical, radiographic, and immunologic perspective. Among the bronchiolar airflow disorders, diffuse panbronchiolitis is related to HLA antigen Bw54, and low-dose, long-term erythromycin appears to be effective therapy. Bronchiolitis obliterans can be classified histologically as constrictive bronchiolitis and as proliferative bronchiolitis obliterans. Idiopathic, postfume, postinfectious, and connective tissue disease bronchiolitis obliterans continue to be rare and often have a poor prognosis. Bronchiolitis obliterans associated with lung transplantation is undergoing intensive investigation with regard to pathogenesis, immunologic study, early detection, and treatment. The lesion appears to be a form of chronic organ rejection. The recognition of the distinctive differences among the bronchiolar airflow disorders by clinicians and clinical investigators is essential for improved patient care, for a greater understanding of the pathogenesis of the disorder, and for development of new therapeutic advances.