Immediate post-operative broncho-alveolar lavage IL-6 and IL-8 are associated with early outcomes after lung transplantation.

INTRODUCTION: Previous studies demonstrated that increased cytokine and chemokine levels, either shortly before or after lung transplantation, were associated with post-transplant outcome. However, small patient cohorts were mostly used, focusing on 1 molecule and 1 outcome. In a large single-center cohort, we investigated the predictive value of immediate post-operative broncho-alveolar lavage (BAL) expression of IL-6 and IL-8 on multiple key outcomes, including PGD, CLAD, graft survival, as well as several secondary outcomes.
MATERIAL AND METHODS: All patients undergoing a first lung transplant in whom routine bronchoscopy with BAL was performed during the first 48 hours post-transplantation were included. IL-6 and IL-8 protein levels were measured in BAL via ELISA.
RESULTS: A total of 336 patients were included. High IL-6 levels measured within 24 hours of transplantation were associated with longer time on ICU and time to hospital discharge; and increased prevalence of PGD grade 3. Increased IL-8 levels, measured within 24 hours, were associated with PGD3, more ECMO use, higher donor paO2 , younger donor age, but not with other short-or long-term outcome. IL-6 and IL-8 measured between 24 and 48 hours of transplantation were not associated with any outcome parameters.
CONCLUSION: Recipient BAL IL-6 and IL-8 within 24 hours post-transplant were associated with an increased incidence of PGD3.