Both autologous and allogeneic hematopoietic stem cell transplants are important therapeutic options for several benign and malignant disorders. Pulmonary complications, although they have become less frequent, remain a significant cause of morbidity and mortality after hematopoietic stem cell transplant. These complications range from bacterial, fungal, and viral pulmonary infections to noninfectious conditions such as diffuse alveolar hemorrhage and idiopathic pneumonia syndrome. Bronchiolitis obliterans syndrome is the primary chronic pulmonary complication, and treatment of this condition remains challenging. This report highlights the advances in the diagnosis and management of the major pulmonary complications after hematopoietic stem cell transplant. It also underscores the need for prospective and multicenter research to have a better understanding of the mechanisms behind these complications and to obtain more effective diagnostic tool and therapeutic options. Key words: Adverse effects, Lung diseases/etiology, Lung diseases/diagnosis, Respiratory tract infections/etiology, Graft versus host disease IntroductionHematopoietic stem cell transplant (HSCT) is increasingly being used for treatment of a wide range of benign and malignant diseases. About 50 000 to 60 000 HSCTs are done annually. 1 Hematopoietic stem cell transplant can be classified as autologous when the stem cells are harvested from the same patient and reinfused after high-dose chemotherapy, whereas, in allogeneic HSCT, the stem cells are donated by another person. Allogeneic HSCT can be related or unrelated and matched or mismatched. The hematopoietic stem cells might be derived from the bone marrow, umbilical cord, or peripheral blood.Hematopoietic stem cell transplant can be a lifesaving treatment of a wide range of neoplastic and nonneoplastic diseases; however, it is still limited by the development of serious complications. Advances in the preparative regimen using a nonmyeloablative preparative regimen, reduced-intensity conditioning transplants, and posttransplant supportive care have contributed to improved overall survival. Despite these advances, pulmonary complications still occur in about 37% of patient after HSCT 2 and are associated with significant morbidity and mortality. In 1 study, the hazard ratio for death due to pulmonary complications was 30. 1 However, there is evidence that the overall mortality and pulmonary complications after HSCT are improving. A recent review of allogeneic HSCT patients in a large transplant center from 1993 to 2007 showed that the risk of nonrelapse mortality decreased by 60% and overall mortality decreased by 41%. In addition, the risk of acute respiratory failure dropped by 36%, with risk of gram-negative bacterial and invasive mold infections decreasing by 39% and 51%. 3 In this study, we provide an update of the main pulmonary complications (both infectious and noninfectious) after HSCT, including an overview of the diagnostic approach and treatment of these complications. Noninfec...

Overall hospital outcome of critically ill patients with HM is improving. However those who require mechanical ventilation or underwent allogeneic HSCT continue to have poor outcome.

Hematopoietic stem cell transplantation (HSCT) is a therapeutic modality for several benign and malignant disorders; however, it is still limited by the development of serious complications. Pulmonary complications are common after both autologous and allogeneic HSCTs with a wide range of infectious and noninfectious disorders. Advances in the prophylaxis and the treatment of infectious pulmonary complications have decreased their incidence although they continue to be an important cause of morbidity and mortality. In contrast, the frequency of noninfectious pulmonary complications associated with HSCT remains unchanged. It is important for the clinician caring for HSCT patients to be familiar with the pulmonary manifestations after HSCT. This report provides an updated review on the pulmonary complications after HSCT, including their incidence, clinical presentation, diagnosis, and management. It also provides an overview of the diagnostic approach to these complications. (Clin Pulm Med 2015;22:230-238) H ematopoietic stem cell transplant (HSCT) is increasingly being used for the treatment of a wide range of benign and malignant diseases. About 50,000 to 60,000 HSCTs are being performed annually. 1 HSCT can be classified as autologous when the stem cells are harvested from the same patient and reinfused after high-dose chemotherapy, whereas in allogeneic HSCT, the stem cells are donated by another person. Allogeneic HSCT can be related or unrelated and matched or mismatched. The hematopoietic stem cells might be derived from the bone marrow, the umbilical cord, or the peripheral blood.HSCT can be a life-saving treatment for a wide range of diseases; however, it is still limited by the development of serious complications. Advances in the preparative regimen using a nonmyeloablative preparative regimen and reduced intensity conditioning transplants (RIT) and posttransplant supportive care have contributed to an improved overall survival. Despite these advances, pulmonary complications still occur in about 37% of the patients after HSCT 2 and are associated with significant morbidity and mortality. In 1 study, the hazard ratio for death due to the pulmonary complications was 30. 1 This article reviews the different pulmonary complications, both infectious and noninfectious, after HSCT, and provides an updated review of the diagnostic approach and the management of these complications.The approach to the diagnosis of pulmonary complications after HSCT should take into consideration the risk factors such as the type of conditioning regimen. Compared with a nonmyeloablative regimen (RIT), the myeloablative regimen is associated with pulmonary complications more frequently, with a higher risk of bacterial infections early after HSCT. 3