Circulating and Intrapulmonary C-Reactive Protein: A Predictor of Bronchiolitis Obliterans Syndrome and Pulmonary Allograft Outcome

Background Elevated C-reactive protein (CRP) levels have been associated with allograft failure and recipient death in renal and cardiac transplantation. Data in lung transplantation (LTx) are lacking. We hypothesized that baseline plasma or bronchoalveolar lavage (BAL) CRP might be prognostic for the long-term outcome after LTx. Methods This retrospective cohort study included 121 LTx recipients. Plasma CRP and BAL CRP, together with cell differentials, and interleukin-6 (IL-6) and IL-8 protein levels, were evaluated at 90 days after LTx and associated with bronchiolitis obliterans syndrome (BOS)-free and overall survival. Results Plasma CRP, BAL CRP, and BAL neutrophilia, but not IL-6 or IL-8, were significantly increased in patients with BOS ≥ 1 or not surviving at 3 years after LTx. In univariate analysis, plasma CRP > 5 mg/liter, elevated BAL CRP levels, and BAL neutrophilia > 15% were predictive for graft failure. In multivariate analysis, only BAL CRP was an independent predictor for graft failure (p = 0.004). A trend was seen for plasma CRP as a predictor (p = 0.077), but BAL neutrophilia was no longer an independent predictor. Conclusions Baseline CRP may be predictive for the long-term outcome after LTx. To confirm the present findings, prospective and longitudinal studies on a larger patient population are required. Elevated C-reactive protein (CRP) levels have been associated with allograft failure and recipient death in renal and cardiac transplantation. Data in lung transplantation (LTx) are lacking. We hypothesized that baseline plasma or bronchoalveolar lavage (BAL) CRP might be prognostic for the long-term outcome after LTx. This retrospective cohort study included 121 LTx recipients. Plasma CRP and BAL CRP, together with cell differentials, and interleukin-6 (IL-6) and IL-8 protein levels, were evaluated at 90 days after LTx and associated with bronchiolitis obliterans syndrome (BOS)-free and overall survival. Plasma CRP, BAL CRP, and BAL neutrophilia, but not IL-6 or IL-8, were significantly increased in patients with BOS ≥ 1 or not surviving at 3 years after LTx. In univariate analysis, plasma CRP > 5 mg/liter, elevated BAL CRP levels, and BAL neutrophilia > 15% were predictive for graft failure. In multivariate analysis, only BAL CRP was an independent predictor for graft failure (p = 0.004). A trend was seen for plasma CRP as a predictor (p = 0.077), but BAL neutrophilia was no longer an independent predictor. Baseline CRP may be predictive for the long-term outcome after LTx. To confirm the present findings, prospective and longitudinal studies on a larger patient population are required.