Persistent increases of BAL neutrophils as a predictor of mortality following lung transplant

Study objectives: To evaluate whether findings from surveillance bronchoscopy predict survival following lung transplantation. Design: Retrospective review and analysis of 498 bronchoscopies with transbronchial biopsy (TBB) and BAL performed in 34 patients after lung transplantation. Setting: University-based, tertiary referral medical center, Patients: Thirty-four patients after lung transplantation, The mean age at transplantation was 49 +/- 9 years; 20 (59%) were female. Twenty-four (71%) underwent single and 10 (29%) underwent bilateral lung transplantation. The most common pretransplantation diagnostic groups were emphysema/COPD without concomitant alpha(1)-antiprotease deficiency (n = 13) and other obstructive disease processes (n = 10). Interventions: Over follow-up, subjects underwent multiple bronchoscopies with TBB and BAL, The median number per subject was 15 (25 to 75% range 13 to 17). Measurements and results: We calculated the overall median BAL WBCs and median percent neutrophils (polymorphonuclear leukocytes [PMNs]) among all of the BALs performed for each subject. We then calculated the mean a SD of those median values. We used Cox proportionate hazards to assess mortality risk. The median overall follow-up observation period for the cohort was 560 days. There were 11 deaths during this period. Twenty-four subjects (71%) had acute rejection (AR) grades 2 to 4 (mild to severe), and nine (27%) had obliterative bronchiolitis (OB) diagnosed by TBB at any point. The mean value for BAL WBCs was 366 +/- 145 x 10(3) per milliliter; for percentage PMNs, the mean was 7 a 10%. Adjusting for age, gender, single vs bilateral lung transplantation, pretransplantation diagnostic group, presence of AR, presence of OB, BAL WBC concentration, and lymphocyte CD4/CD8 ratio, PMN pet-cent was a significant predictor of mortality (p = 0.02). Conclusions: Ongoing inflammation manifested by an increased percentage PMNs over repeated bronchoscopies predicts mortality following lung transplantation. Biopsy data alone may be insufficient to identify posttransplantation patients at risk of poor outcome.