Pulmonary complications after allogeneic hematopoietic stem cell transplantation

The respiratory tract is one of the most common and serious sites for complications in HSCT patients. In this project the incidence, outcome, and risk factors for patients with infectious or non-infectious pulmonary complications were studied. Bronchoscopy and pulmonary function tests (PFTs) were evaluated as diagnostic tools. Between 1975 and 2003, pneumonia was found to be the most common cause of early death (within 100 days) after HSCT. The cumulative incidence was 5.6% compared to 10% for all other causes. However, this three-decade study exhibited a striking change over time: the cumulative incidence of early death due to pneumonia decreased from 8.9% in the first decade studied to 2.8% in the third decade. In the fourth study (2000-2009) this incidence was 3.2%. However, death from overall pneumonia (early and late pneumonia) was 10.5%, indicating that pneumonia is still a common cause of death. Bronchoalveolar lavage (BAL) was shown to be a safe and useful diagnostic tool to establish the causative pathogens of pneumonia: this procedure contributed to the diagnosis in 43 of 68 (63%) episodes of pneumonia in the second study (1998-2004). BAL was especially important for establishing pneumonia due to Aspergillus and Cytomegalovirus. Comparing the results of other culture specimens, these pathogens would not have been found pre-mortem without this procedure. In 42 (62%) cases of pneumonia, the treatment was either changed or continued according to the BAL results. PFTs are also important diagnostic tools. We considered FEV1 as the most important parameter for detection and monitoring the development of BO, a progressive and persistent non-infectious complication characterized by airflow obstruction. Furthermore FEF75 was reduced in 28% patients with BO and thus may serve as an early warning. Patients who developed BO late (> 1 year after HSCT) had a better five-year survival than those with an early onset BO. Statistical analyses revealed that risk factors for early pneumonia death also changed over ...