Bronchoscopy has seen rapid evolution in the last 5 years and a variety of new diagnostic techniques are now available, which the majority of physicians are unaware of. Despite these advances, not all patients will benefit from a bronchoscopic work up of pulmonary infections. Many physicians are unware of the variant diagnostic yield of different bronchoscopic techniques, which leads to improper utilization and incorrect selection of the appropriate bronchoscopic diagnostic technique for a specific patient.

Pulmonary complications are reported in about 20 - 60% of hematopoietic stem cell transplant recipients and are important causes of mortality and morbidity. Specifically, pulmonary complications are generally more common after allogeneic hematopoietic stem cell transplant and are reported in up to 70% of patients. A variety of infectious complications secondary to bacterial, viral, fungal infections can occur and comprise greater than 60% of all pulmonary complications. Identification of the exact cause of these infectious complications has remained elusive in the hematopoietic stem cell transplant patient population. Conventional bronchoscopy has been the mainstay diagnostic approach with bronchoalveolar lavage or transbronchial biopsy. Despite widespread utilization of these diagnostic modalities they have been demonstrated to have limited diagnostic yield in this patient population. 

The morbidity and mortality related to pulmonary complications in hematological malignancy patients, particularly those who have undergone hematopoietic stem cell transplant, is very high. Early diagnosis and prompt treatment has been demonstrated to lower the morbidity and mortality related to these complications. A significant number of these patients require intensive care support during their hospitalization. By being able to increase the ability to diagnose infectious pulmonary lesions, clinicians will be able to greatly reduce the morbidity and mortality these patients experience.