Neutropenia is Associated with an Increased Risk of Subsequent Antibody-Mediated Rejection in Lung Transplant Recipients

Purpose

Our aim was to determine the association between the development of post-transplant neutropenia and subsequent antibody-mediated rejection (AMR) in a population of adult lung transplant recipients.

Methods

We performed a single center retrospective cohort study of adult lung transplant recipients between 2008 and 2013. Neutropenia was defined as an absolute neutrophil count (ANC) <= 1500 and categorized as mild (ANC<1500), moderate (<1000) or severe (ANC<500). AMR was defined according to ISHLT consensus guidelines. Cox Regression analysis was performed to evaluate AMR-free survival in patients with and without post-transplant neutropenia.

Results

The cohort included 228 lung transplant recipients, 101 (42.1%) of whom developed neutropenia. Of those patients who developed neutropenia, 42 had mild neutropenia, 34 had moderate neutropenia and 25 had severe neutropenia. Patients with Neutropenia had a significant increased risk of subsequent AMR (OR 3.16, 95% CI 1.37-7.28, p=0.005). Additionally, patients who developed neutropenia had decreased AMR-free survival (HR for death 2.90, 95% CI 1.32-6.37, p=0.008). This relationship appeared to correlate with degree of neutropenia. Patients with severe moderate and severe neutropenia had lower AMR-free survival than patients with mild or no neutropenia.

Conclusion

The development of neutropenia is associated with an increased risk of subsequent AMR in lung transplant recipients. Further investigation into the underlying mechanism of this association is warranted.