Analysis of clinical characteristics and risk factors for Staphylococcus aureus disseminated infection secondary to acute osteoarticular infections in children.

Background: The aim of this study was to investigate the risk factors associated with Staphylococcus aureus (S. aureus) disseminated infection (DSAI) that occurs secondarily to acute osteoarticular infections (OAI) in children.

Methods: A retrospective analysis of 131 pediatric patients with acute OAI (July 2012-March 2024) was conducted. Patients were categorized into a DSAI group (33 cases) and a non-DSAI group (98 cases). Data analyzed included age, gender, pediatric intensive care unit (PICU) admission, surgical delay, initial symptoms, highest pre-hospital fever, inflammatory markers, pathogen type (MSSA/MRSA), bacteremia, antibiotic duration, postoperative fever length, surgeries (≥ 2), hospital stay, and prognosis.

Results: DSAI primarily affected the lungs, brain, and thorax, with femur and hip joints being the most involved OAI sites. Fever (45.45%) and limb swelling/pain (42.42%) were common symptoms. The DSAI group showed significantly higher CRP levels, bacteremia incidence, MRSA infections, PICU admissions, surgical delays, ≥ 2 surgeries, longer postoperative fever, prolonged hospital stays, and worse prognosis (P < 0.05). No significant differences were found in age, gender, pre-admission time, initial symptoms, highest fever, WBC count, ESR, antibiotic duration, or neutrophil percentage (P > 0.05). Logistic regression identified bacteremia (OR: 32.232, 95% CI: [2.558-406.068], P = 0.007), CRP > 162.375 mg/L (OR: 7.499, 95% CI: [2.044-27.513], P = 0.002), and surgical delay > 9.50 days (OR: 7.462, 95% CI: [1.828-30.459], P = 0.005) as independent risk factors.

Conclusion: DSAI complicates OAI, leading to a severe course and poor prognosis. High vigilance and early intervention are crucial for pediatric patients with these risk factors.