Clinical index to predict bacteraemia caused by staphylococci

Area of Science:

• Infectious Diseases
• Clinical Microbiology
• Epidemiology

Background:

• Bacteraemia caused by Staphylococcus aureus and coagulase-negative staphylococci poses a significant clinical challenge.
• Identifying patients at high risk is crucial for timely and effective treatment.

Purpose of the Study:

• To define risk factors associated with Staphylococcus aureus (S. aureus) and coagulase-negative staphylococci (CoNS) bacteraemia.
• To develop models for identifying patients who would benefit from empiric anti-staphylococcal antibiotic therapy.

Main Methods:

• Observational, prospective study for derivation set (n=1410) and retrospective analysis for validation set (n=1040).
• Logistic regression models were used to identify risk factors and stratify patients.
• Data collected from two university hospitals in Israel and the UK.

Main Results:

• For S. aureus bacteraemia, risk factors included infection focus, haemodialysis, intravenous drug abuse, and orthopaedic ward acquisition.
• For CoNS bacteraemia, risk factors included central/peripheral intravenous catheter, preterm neonate, low temperature, and low white blood cell count.
• Models effectively stratified patients into low, intermediate, and high-risk groups for both types of staphylococcal bacteraemia (P < 0.0001).

Conclusions:

• The study successfully defined distinct risk factor profiles for S. aureus and CoNS bacteraemia.
• Empiric anti-staphylococcal antibiotic treatment is recommended for patients identified in high-risk groups.
• These findings can guide clinical decision-making for empiric antibiotic selection in suspected staphylococcal bloodstream infections.