Prospective Study of Belated Pulmonary Complications Occurring in Children Treated With Allogeneic Hematopoietic Stem Cells.

It's a multicenter prospective study in France. All children under 18 years are included, just before the HSCT. The functional test before the HSCT at 6, 12, 18, 24, 30 and 36 months will be collected and a cardiopulmonary exercise test is done one and three years after the HSCT. Thoracic tomodensitometry is done before the HCT and after at 6, 12, 24 and 36 months. All data will be collected upon the HSCT, the infections before and after the HSCT, the respiratory symptoms, and the treatment. Bronchia alveolar lavage and serum will be collected and frozen during the study. The inclusion will be done during two years and children will be following during three years. The purpose is to evaluate the prevalence, the course of PFT abnormalities before and after transplant, and to detect risk factor for PC.