Long-term preservation of allograft function remains an elusive goal following lung transplantation. Despite current immunosuppressive strategies, bronchiolitis obliterans syndrome (BOS), a disorder characterized by irreversible airflow obstruction and presumed to be a consequence of chronic allograft rejection, develops in the majority of lung transplant recipients.1
Although its course may be interrupted by periods of relative stability, BOS is invariably a progressive disorder that ultimately robs the recipient of the functional gains that accompanied transplantation. A wide range of therapies, centering on augmentation of the magnitude of immunosuppression, have been employed, but there is no consensus on the optimal approach. At best, treatment appears to slow the rate of decline rather than to permanently arrest or reverse the process. Retransplantation represents the only definitive option, but lingering questions about optimal surgical approach, patient selection, outcomes, and ethics have tempered its widespread acceptance.