Pretransplant Aspergillus colonization of cystic fibrosis patients and the incidence of post-lung transplant invasive aspergillosis

Background Invasive aspergillosis (IA) is an important cause of morbidity and mortality among patients undergoing lung transplant. Cystic fibrosis-lung transplant recipients (CF-LTRs) may be at greater risk of IA following lung transplantation because of the presence of Aspergillus in their airways before transplantation. This study evaluated the impact of pretransplant Aspergillus colonization on the risk for IA among CF-LTRs. Methods A single-center retrospective cohort study of CF-LTRs was conducted between 2006 and 2010. Respiratory tract cultures before transplantation were reviewed to identify patients with pretransplant Aspergillus colonization. Patients with positive Aspergillus sputum culture or positive bronchoalvelolar lavage (BAL) galactomannan after transplantation were classified as having colonization or disease according to the International Society of Heart and Lung Transplantation criteria. Results A total of 93 CF patients underwent lung transplantation. Seventy percent (65/93) of CF-LTRs had pretransplant Aspergillus colonization. Thirty-six patients had positive intraoperative Aspergillus culture from the native lung BAL. Overall, 22.5% (20/93) of CF-LTRs developed IA. Median time to IA was 42 days following transplantation. Positive intraoperative Aspergillus culture (OR 4.36, 95% CI 1.35-14.05, P=0.01) and treatment for acute cellular rejection within 90 days after transplantation (OR 3.53, 95% CI 1.03-12.15, P=0.05) were independent risk factors for IA. Antifungal prophylaxis was administered to 61% (57/93) of CF-LTRs. One-year mortality rate was 16% (15/93). IA was not associated with increased risk of death (OR 2.10, 95% CI 0.62-7.06, P=0.23). Conclusion Pretransplant Aspergillus colonization is frequent among CF-LTRs and a positive intraoperative Aspergillus culture produced a fourfold higher risk of developing IA.