INFECTION IN THE TRANSPLANTED AND NATIVE LUNG AFTER SINGLE-LUNG TRANSPLANTATION

Objective: To analyze a single-center experience with infectious complications of single lung transplantation (SLT) with special emphasis on risk factors for infection in the transplanted and native lung. Design: Consecutive case series. Setting. University teaching hospital. Patients: Fifteen consecutive SLT recipients (mean age, 43 years; 9 men and 6 women). Mean follow-up was 337 days. Results: Fifteen patients had 24 infectious episodes (1.6 per patient) of which 83 percent were life-threatening, 79 percent involved the lung, airway, or pleural space, and 79 percent occurred in the first 4 months after transplantation. Despite this high infectious morbidity, there were no infectious deaths. The most important infections were bacterial pneumonia (n = 10), cytomegalovirus (CMV) pneumonia (n = 5), and bronchial anastomotic infections (n = 3). Significant risk factors for bacterial pneumonia were a diagnosis of primary or secondary pulmonary hypertension (p<0.05) and the presence of airway complications of stenosis or dehiscence (p<0.05). No risk factors for overall lung infections were identified. The native lung was involved in 6 of 16 lung infections and was the exclusive site of infection in 4 cases. Underlying disease in the native lung may have predisposed to infection at that site by a mechanism of inadequate blood flow or impaired ventilation. Three bronchial anastomotic infections (Pseudomonas, Candida, Aspergillus) occurred, all with dehiscence of the anastomosis. These were highly morbid but resolved with antibiotics, stent placement, and surgical retention in two of the three cases. The five episodes of CMV pneumonia caused mild (four patients) or moderate (one patient) dysfunction and responded to antiviral agents without relapse. Conclusion: The frequency, complexity, and morbidity of infections after SLT were great, but most infections were manageable and good outcomes were achieved. A pretransplant diagnosis of pulmonary hypertension or posttransplant occurrence of bronchial stenosis or dehiscence were associated with a higher rate of bacterial pneumonia. The underlying disease in the native lung may predispose to infection at that site.