CT of complications in pediatric lung transplantation.

The authors review the computed tomographic (CT) findings following single and double lung transplantation in children to show the spectrum of complications. The most common parenchymal complications following transplantation include acute rejection; chronic rejection or bronchiolitis obliterans; bacterial, viral, and fungal infections; and lymphoproliferative disorders. In acute and chronic rejection, CT shows ground-glass attenuation and interlobar septal thickening. The same CT findings are seen in bacterial and viral infections, with occasional pulmonary abscess seen in the former. Fungal infections are characterized by cavitary lesions, air-space disease, and mediastinal adenopathy on CT scans. In lymphoproliferative disorders, CT demonstrates pulmonary nodules or soft-tissue masses. The most frequent posttransplantation airway complications include stenosis, stent migration, and dehiscence. Dehiscence, which usually results from ischemia at the anastomosis site, is evident on CT scans as a disrupted airway and extraluminal air collections. CT is particularly important in the evaluation of airway complications because the CT results can significantly affect patient management. In parenchymal disease, CT often cannot aid in establishing a specific diagnosis, but it can be used to determine a site for biopsy, document extent of disease, and follow up results of treatment.