Early Detection and Management of Bronchiolitis Obliterans Syndrome Following Pediatric Hematopoietic Stem Cell Transplantation

Each enrolled patient will receive pulmonary function testing every three months. Pulmonary function testing includes spirometry, plethysmography, and diffusion capacity measurements.

All patients who have evidence of early airflow obstruction on pulmonary function testing will be started on FAM therapy. Early airflow obstruction is defined by a FEV1 decline of ≥10% predicted in addition to a FVC \<0.8.