BRONCHIOLITIS OBLITERANS IN ATAXIA-TELANGIECTASIA

Pulmonary disease was studied in four patients with ataxia-telangiecta sia. Immunodeficiency was characterized by lymphopaenia, hypo-gammaglo bulinaemia and decreased T-cell response to phytohaemagglutinin stimul ation in mixed lymphocyte cultures. All four patients died from respir atory failure. Autopsy revealed that all four patients suffered from b ronchiolitis obliterans in all lobes. Immunohistochemical examination demonstrated expression of MHC class II antigens on bronchiolar epithe lium. Pulmonary infections in ataxia-telangiectasia patients included a case of mycoplasma pneumonia, one of cytomegalovirus pneumonia and o ne of Pseudomonas aeruginosa infection. The aetiology and immunologica l background of bronchiolitis obliterans are discussed. Bronchiolitis obliterans is a characteristic finding in ataxia-telangiectasia and ma y be due to the underlying immune deficit.