CT findings of pulmonary complications after hematopoietic stem cell transplantation

Pulmonary complications after hematopoietic stem cell transplantation (HSCT) follow a predictable timeline. The common abnormalities in pre-engraftment phase (within 30 days after HSCT) are infectious and non-infectious complications. The complications are mainly pulmonary edema, diffuse alveolar hemorrhage and idiopathic pneumonia syndrome. During the early post-transplantation phase (30 to 100 days), cytomegalovirus (CMV) and invasive fungal infections are commonly seen. Non-infectious diseases commonly seen are idiopathic pneumonia syndrome, acute graft-versus-host disease (GVHD), acute radiation pneumonitis and pulmonary cytolytic thrombi. During the late post-transplantation phase (after 100 days), non-infectious complications are dominated. The chronic graft-versus-host disease is the most common complication. CT features of the pulmonary complications in pre-engraftment phase, post-transplantation phase and late post-transplantation phase were reviewed. (authors)