The role of flexible bronchoscopy in detecting rejection following lung transplantation was studied at four- to 10-day intervals in 47 dogs, including 31 allograft recipients, ten autograft recipients, and six controls without operations.
Anastomotic narrowing inevitably occurred within the first postoperative week. After allografting without immunosuppression, anastomotic narrowing was progressive. Despite rejection, segmental and subsegmental bronchi were remarkably normal. During rejection delayed by immunosuppression, there was a 33% reversibility rate for anastomotic narrowing. Bronchial biopsies were not helpful. Mucosal exudate and pus were regularly seen when pneumonia was the cause for graft failure.
We conclude that progressive bronchial anastomotic narrowing is a manifestation of rejection. Bronchoscopy will be helpful in management of human lung transplant recipients by identifying anastomotic stenosis and early endobronchial signs of pneumonia.