BRONCHIOLITIS OBLITERANS - PATHOGENESIS, PREVENTION, AND MANAGEMENT

Increasing early success-post lung transplant has been tempered by the longterm development of histologic bronchiolitis obliterans (OB) or o f the progressive airway obstruction which is called bronchiolitis obl iterans syndrome (BOS). Multiple lines of evidence suggest that OB/BOS is due to an injury directed against the epithelial cells in the airw ays of the donor lung by the immune system of the recipient. Acute rej ection is the strongest risk factor for the subsequent development of this process. Efforts to prevent or minimize acute rejection may reduc e the prevalence of OB/BOS. Results of treatment with augmented immuno suppression have been disappointing but the treatment of complicating infections in the allograft can be beneficial. Multicenter studies are needed to assess the efficacy of new immunosuppressive agents in prev enting or treating OB/BOS.