Eosinopenia Associated with Infection is an Independent Risk Factor for 28-day Mortality in Staphylococcus aureus Bloodstream Infection

Aims: This retrospective study aimed to evaluate the impact of eosinopenia on 28-day mortality in Staphylococcus aureus bloodstream infection (SABSI).

Methods: A retrospective study was designed to evaluate the impact of eosinopenia on 28-day mortality in SABSI.

Results: Patients who were ≥16 years old with SABSI at Sun Yat-Sen Memorial Hospital between January 1st 2014 and December 31st 2018 were included. The overall 28-day mortality of all patients was 14.3% (44 out of 307). Patients with eosinopenia in the onset of SABSI had a significantly higher 28-day mortality than those without eosinopenia (22.4% vs 6.5%; P<0.01). For patients who developed SABSI after the first 48 hours in the hospital, eosinophils decreased significantly from the baseline (P<0.01). Kaplan–Meier survival curve showed that patients with eosinopenia had a lower survival rate than those without eosinopenia (P<0.01). Multivariate Cox regression analysis revealed that eosinophils in the onset of SABSI were associated independently with 28-day mortality (hazard ratio [HR], 2.84; 95% confidence interval [CI], 1.36–5.91; P<0.01).

Conclusion: Eosinopenia associated with infection might be an independent risk factor for 28-day mortality in SABSI.