Incidence of bacterial blood stream infections in patients with acute GVHD.

Bacterial bloodstream infections (BSI) can be a substantial contributor to complications of GVHD treatment. The aim of this study was to determine the risk for BSI from neutrophil engraftment through day 100 post transplant in patients with acute GVHD (AGVHD) based on organ involvement and severity. Patients (n = 4064) who underwent an allogeneic hematopoietic stem cell transplant (HCT) reported to the CIBMTR registry were analyzed. Grade II-IV AGVHD occurred in 1607 (39.5%) patients and was associated with a greater day-100 incidence of post engraftment BSI than with grade 0/I (24.9 vs. 15.3%). Patients with grade III/IV AGVHD had the highest BSI risk (HR 2.45; 95% CI 1.99-3.0; p < 0.0001). Lower GI involvement increased BSI risk (HR 1.54; 95% CI 1.17-2.02; p = 0.0019). BSI post-engraftment through day 100 was associated with worse survival (HR 1.64, 95% CI 1.43-1.87; p < 0.001) and higher non-relapse mortality (NRM), (HR 2.22; 95% CI 1.91-2.59; p < 0.001). Those with stage III/IV GI involvement are at highest risk for BSI. Future studies evaluating novel methods for preventing BSI in these high risk populations are needed to reduce mortality associated with AGVHD.