Abstract:Objective To investigate the clinical characteristics, risk factors, treatment and prognosis of streptococcal bloodstream infection (BSI). Methods Patients with positive Streptococcus blood culture in a tertiary teaching hospital in East China from January 2018 to December 2021 were selected as the research subjects, their clinical medical data were collected, healthcare-associated infection (HAI) and risk factors for prognosis were retrospectively analyzed. Results A total of 151 patients with streptococcal BSI were included in the analysis, with an average age of (55.5±17.9) years old, 45.70% were >60 years old, male patients accounted for 61.59%, and 89.40% of patients had underlying diseases such as solid tumors, heart valve disease, hepatobiliary diseases, and hypertension. The common risk factors for streptococcal BSI included surgery, immunosuppression, and disruption of skin or mucosal integrity(all P < 0.05). HAI accounted for 25.17% (n=38); common underlying diseases included hepatobiliary diseases, solid tumors, hematologic disorders, and hypertension. Patients with HAI had longer hospital stays and higher acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ scores) compared with patients with community-associated infection (CAI) (all P < 0.05). Among the 151 detected bacterial strains, the susceptibility rates of α-hemolytic Streptococcus (n=112, except Streptococcus pneumoniae) to penicillin, levofloxacin, and ceftriaxone were 71.43%, 80.38%, and 91.07%, respectively. β-hemolytic Streptococcus (n=29) were 100% susceptible to penicillin; Streptococcus pneumoniae had a susceptibility rate of 50.00% to penicillin. The 30-day allcause mortality of 151 patients was 6.62% (n=10), and the attributable mortality was 2.65% (n=4). Binary logistic regression analysis showed that shock (OR=13.690, 95%CI: 1.482-126.470) and Pitt bacteremia score ≥4 (OR=10.461, 95%CI: 1.042-105.005) were independent risk factors for mortality in patients with streptococcal BSI. Conclusion Streptococcal BSI is mainly CAI, and there are multiple risk factors for hospital-associated streptococcal BSI. Shock and Pitt bacteremia scores ≥4 are independent risk factors for death in patients with streptococcal BSI.