Bronchoscopic Evaluation of Pulmonary Complications in Patients Undergoing Reduced-Intensity Versus Full-Intensity Transplants.

Pulmonary complications are common following hematopoietic stem cell transplantation (HSCT). The role of fiberoptic bronchoscopy with broncho-alveolar lavage (BAL) in recipients of reduced-intensity (RI) and full intensity (FI) transplants is now reported. Between January 2001-May 2008, 803 allogeneic transplants (212 RI, 591 FI) were performed on 784 patients at the University of Michigan Medical Center. Pulmonary complications, defined as either

• hypoxia > 24 hours, or

• clinical/radiographic features of pneumonitis, were identified in 313 (39.9%) patients post-transplant.

Bronchoscopy was performed on 265 (84.7%) patients with pulmonary complications, including 69 patients undergoing RI transplants (median age 56 yrs, 10–68 yrs) and 196 patients undergoing FI transplants (median age 41 yrs, 1–64 yrs). The time to BAL was similar for recipients of RI when compared to recipients of FI transplant [median: 89 days (0–1854 days) vs. 104 days (7–1533 days)]. Pathogenic organisms were identified in 31.8% (RI) and 25.2% (FI) of BAL procedures. Invasive fungi were the most commonly identified organisms, identified on 48.1% (RI) and 45.2% (FI) of BALs in which pathogens were noted. The incidence of bacterial, viral (including CMV), and mycobacterial pulmonary infections were similar in recipients of RI and FI transplants. The frequency with which pathogens were identified varied with the timing of the bronchoscopy (see Table), with non-infectious pulmonary complications twice as likely to occur in the first 100 days post-transplant in FI than RI transplant recipients (p < 0.05). The BAL led to a change in medical management in 54.1% (RI) and 59.3% (FI) of cases respectively, with modifications in antimicrobial therapy in 38.8% (RI) and 42.1% (FI). The bronchoscopy led to modifications in immunosuppressive therapy in 27.1% (RI) and 27.6% (FI) of cases. BAL procedural related complications were rare in both groups, with pulmonary hemorrhage and transient hypoxemia occurring in < 2.5% of all patients undergoing a BAL.

Conclusion: The incidence of pulmonary complications, as evaluated by bronchoscopy post HSCT, was similar for recipients of RI and FI conditioning regimen. Within the first 100 days post-transplant, non-infectious etiologies for pulmonary dysfunction were significantly more common in FI than RI patients. There were no other significant differences in the timing of pulmonary complications or the type of pathogenic organisms identified following a FI or RI transplant. Broncho-alveolar lavage is a safe procedure in patients following allogeneic transplants, altering medical management in over 50% of cases. Time post-transplant and % BAL with a pathogenic organism identified