Bloodstream infections in hospitalized adults with COVID-19: clinical characteristics and outcomes.

Background: Bloodstream infections (BSIs) are serious complications in hospitalized coronavirus disease 2019 (COVID-19) patients and may have worsened clinical outcomes. We evaluated clinical characteristics and outcomes of COVID-19 patients with BSI and compared them to a matched non-COVID-19 BSI cohort.

Methods: A retrospective cohort study was conducted at a tertiary medical center in southern Taiwan, and included adult patients hospitalized with concurrent COVID-19 and bloodstream infection (BSI) from January 2022 to April 2023. We compared survivors and non-survivors and assessed risk factors for in-hospital mortality. Propensity score matching (1:10) was used to compare COVID-19 BSI patients with non-COVID-19 BSI patients from 2017 to 2019.

Results: Among 104 COVID-19 patients with BSI, 26.0 % died during hospitalization. Male sex (adjusted OR (aOR) 5.87, 95 % confidence interval (CI) 1.51-22.83, p = 0.011), diabetes mellitus (aOR 3.89, 95 % CI 1.07-14.21, p = 0.040), Ct value ≤ 20 at diagnosis (aOR 5.15, 95 % CI 1.06-24.98, p = 0.042), Pitt bacteremia score ≥4 (aOR 5.84, 95 % CI 1.48-23.01, p = 0.012), and hospital-onset BSI (aOR 19.45, 95 % CI 3.33-113.54, p < 0.001) were independently associated with mortality. Hospital-onset BSI cases had higher rates of resistant and polymicrobial infections. Compared to non-COVID-19 BSI patients, COVID-19 BSI cases had more primary BSI and higher inappropriate empirical therapy use, though COVID-19 status itself was not independently associated with 30-day mortality after matching.

Conclusions: BSIs in COVID-19 patients are linked to high mortality, particularly in hospital-acquired infections. Timely diagnosis, risk stratification, and targeted therapy remain crucial.