Minimal acute rejection in pediatric lung transplantation--does it matter?

In adult lung transplantation, a single minimal AR episode is a significant predictor of BOS independent of other factors. However, the significance of single minimal AR episodes in children is unknown. A retrospective, multi-center analysis was performed to determine whether isolated single AR episodes are associated with an increased BOS risk in children. Risk factors for BOS, death, or re-transplantation, and a combined outcome of BOS, death, or re-transplantation were assessed. Original data included 577 patients (<21 yr of age). A total of 383 subjects were eligible for the study. Fifteen percent of patients developed BOS, and 13% of patients either died or underwent re-transplant within one-yr post-transplant. In the multivariable survival model for time to BOS, there was no significant risk to developing BOS after a single minimal AR (A1) episode (HR 1.7, 95% CI 0.64-4.8; p=0.28). Even after a second minimal AR episode, no significant risk for BOS was appreciated. However, a single episode of mild AR (A2) was associated with twice the risk of BOS within one-yr post-transplant. In this select cohort, a single minimal AR episode was not associated with an increased risk for BOS within one yr following lung transplantation, in contrast to previous reports in adults. Copyright (c) 2010 John Wiley & Sons A/S.