Prediction Rules for Ruling Out Endocarditis in Patients With Staphylococcus aureus Bacteremia

Area of Science:

• Infectious Diseases
• Cardiology
• Clinical Diagnostics

Background:

• Staphylococcus aureus bacteremia (SAB) frequently complicates with infective endocarditis (IE).
• Accurate risk stratification is crucial for timely IE diagnosis in SAB patients.
• Existing clinical prediction scores aim to identify high-risk individuals.

Purpose of the Study:

• To compare the diagnostic accuracy of three clinical prediction scores: POSITIVE, PREDICT, and VIRSTA.
• To evaluate the ability of these scores to classify the likelihood of IE in patients with SAB.
• To determine if any score meets a high negative predictive value (NPV) threshold for excluding IE.

Main Methods:

• A prospective cohort study enrolled 477 adult patients with SAB across 7 Dutch hospitals.
• The modified Duke Criteria served as the reference standard for definite endocarditis.
• Sensitivity, specificity, and NPV were calculated for each score.

Main Results:

• 18.2% of patients had definite endocarditis.
• The VIRSTA score demonstrated the highest sensitivity (98.9%) and NPV (99.3%).
• Only VIRSTA met the target NPV of >=98% for excluding endocarditis, though it classified more patients as high-risk.

Conclusions:

• The VIRSTA score is the most accurate among the evaluated scores for ruling out IE in SAB.
• High NPV of VIRSTA aids in excluding endocarditis, but may increase TEE utilization.
• Further refinement may be needed to balance diagnostic accuracy with resource utilization.