A clinicopathologic study on three cases of constrictive bronchiolitis

We describe the characteristic clinical and pathologic findings of three ca ses of constrictive bronchiolitis. All three patients were middle-aged wome n with chronic respiratory illness characterized by chronic cough, dyspnea, mild to severe obstructive pulmonary dysfunction, relatively normal chest radiographs with occasional peribranchial infiltration, and lack of respons e to bronchodilators or prednisolone. The patients also had medical disease s such as non-Hodgkin's lymphoma and hyperprotactinemia in case 1 and 3, re spectively. None of the patients smoked cigarettes and had clinical evidenc e of recent viral lower respiratory tract infection. Histologic study by op en lung biopsy revealed a spectrum of changes ranging from active cellular bronchiolitis to obliterative peribronchiolar fibrosis. The intervening int erstitial and alveolar areas showed no remarkable lesion. Immunohistochemic ally, the bronchiolar or peribronchiolar inflammatory infiltrates mainly co mprised of mixed T- and B-lymphocytes. It may be possible that the active f orm of constrictive bronchiolitis is initiated by attendant lymphocytic inf lammation of the airways, which is followed by fibrous obliteration of bron chioles.