Air-leak Syndrome by Pleuroparenchymal Fibroelastosis after Bone Marrow Transplantation.

Objective Air-leak syndrome (ALS) is a life-threatening pulmonary complication following allogeneic bone marrow transplantation (allo-BMT) which is thought to be associated with graft-versus-host disease (GVHD). Recently, it has been reported that pleuroparenchymal fibroelastosis (PPFE) also occurs after allo-BMT and often causes ALS. We sought to extract common features of ALS caused by PPFE after allo-BMT. Methods The clinical data of patients who developed ALS caused by PPFE after undergoing allo-BMT (ALS-PPFE) between April 1996 and December 2007 at our institution were collected and reviewed retrospectively. The clinical findings, radiological and pathological features and treatment outcomes of ALS-PPFE were assessed. Results Five patients who developed ALS had histologically proven PPFE (four men, one woman: median age, 37 years). The age of onset of ALS-PPFE was 13 to 109 months (median, 68.8 months) after BMT. Alkylating agents were used as conditioning chemotherapy for BMT in all patients. Only one patient developed chronic GVHD (limited type). The common radiological findings were subpleural thickening and traction bronchiectasis predominantly in the bilateral upper lung fields. The histological pulmonary specimens showed no findings of bronchiolitis obliterans or GVHD. Immunosuppressive therapy was not effective in any of the cases, and all patients died of respiratory failure with or without lung transplantation. Conclusion ALS-PPFE is an extremely late-onset noninfectious pulmonary complication of allo-BMT. This complication is progressive, resistant to immunosuppressive treatment and has a poor prognosis. No association was found between PPFE and GVHD.