Prior cytomegalovirus reactivation may lead to worse bacterial bloodstream infection outcomes in HSCT patients

Background

Cytomegalovirus (CMV) reactivation is common after transplantation, and may further augment natural killer (NK) cell activity, which has a protective role through both innate and adaptive immune responses. Bacterial bloodstream infections (BBSIs) are a common cause of morbidity and mortality in patients following allo-HSCT. Therefore, we hypothesized that CMV reactivation might play a role in the outcomes of patients with BBSI after allo-HSCT.

Objectives

We investigated the role of CMV reactivation in the clinical outcomes of patients with BBSI after allo-HSCT.

Study design

A total of 101 BBSI patients (45 non-CMV reactivation [NCR] and 56 CMV reactivation [CR]) were included in the study following allo-HSCT. Clinical and laboratory findings were reviewed, and differences were tested using the Chi-square (χ²) test. Multivariate Cox regression analysis was used to calculate hazard ratios for between-group comparisons of clinical outcomes.

Results

CMV reactivation had a negative prognostic impact on the clinical outcomes of BBSI patients following allo-HSCT with regard to the 1-year overall survival time (HR, 3.583; 95% CI, 1.347–9.533; P = 0.011). In 56 BBSI patients with CMV reactivation following allo-HSCT, the 1-year mortality among those in whom CMV was reactivated first (CRF) was significantly elevated (56.5% vs. 18.2%, P = 0.003) compared with patients in whom the BBSIs occurred first (BOF).

Conclusions

CMV reactivation in BBSI patients is related to higher mortality 1-year after allo-HSCT. Further studies on a larger cohort are needed to better understanding the mechanism of CMV reactivation influence.