Incidence, Clinical Characteristics and Outcomes of Persistent Staphylococcus aureus Bacteremia in a Chinese Tertiary Care Hospital: A Single-Center Retrospective Study.

Purpose: Persistent Staphylococcus aureus bacteremia (pSAB) poses significant clinical challenges because of its association with poor outcomes, including relapse and mortality. Despite its clinical importance, data on pSAB in the mainland Chinese population remain limited. This study aimed to investigate the prevalence, clinical characteristics, and predictors of pSAB in a tertiary hospital in China.

Patients and methods: We conducted a retrospective case-control study at a large tertiary-care hospital in China from 2020 to 2024. Patients with Staphylococcus aureus bacteremia (SAB) were categorized into persistent and nonpersistent groups on the basis of the duration of bacteremia (>48 hours). Clinical characteristics, management, and outcomes were compared. Multivariate logistic regression was used to identify independent risk factors for pSAB.

Results: Among 499 patients with SAB, 48 (9.6%) met the criteria for pSAB, with the incidence peaking at 13.9% in 2024. Compared with the non-pSAB group, the pSAB group had higher rates of infective endocarditis (p=0.002), a CCI ≥7 (p=0.036), metastatic infection (p=0.007), and preadmission fever ≥7 days (p=0.026). They more frequently underwent surgical intervention (p=0.041), received dual anti-MRSA therapy (p<0.001), and less often received β-lactam monotherapy (p=0.001). pSAB was associated with prolonged fever (p=0.014), a hospital stay ≥7 days after SAB onset (p=0.002), increased 30-day mortality (p=0.036), and increased 3-month relapse (p=0.001). Multivariate analysis revealed a CCI ≥7 (OR=4.09; 95% CI: 1.19-14.00; p=0.025), infective endocarditis (OR=8.66; 95% CI: 1.52-49.03; p=0.015), and preadmission fever ≥7 days (OR=5.06; 95% CI: 1.61-15.90; p=0.006) as independent predictors of pSAB.

Conclusion: The incidence of pSAB is increasing in China and is associated with complex clinical features and adverse outcomes. Severe comorbidities, infective endocarditis, and prolonged fever before admission are significant predictors of pSAB. Early identification and aggressive source control are critical for improving the outcomes of high-risk patients.