Performance of the Modified Boston and Philadelphia Criteria for Invasive Bacterial Infections

Area of Science:

• Pediatrics
• Infectious Diseases
• Clinical Diagnostics

Background:

• Established Boston and Philadelphia criteria for serious bacterial infections in infants require reevaluation.
• Recent data on the diagnostic accuracy of these criteria in young infants is limited.

Purpose of the Study:

• To assess the performance of modified Boston and Philadelphia criteria in identifying invasive bacterial infections (IBIs) in infants aged 29 to 60 days.
• To determine the accuracy of these criteria in diagnosing bacterial meningitis and bacteremia.

Main Methods:

• A multicenter cohort study included infants aged 29 to 60 days with cerebrospinal fluid (CSF) and blood cultures.
• Modified Boston criteria: peripheral WBC ≥20,000, CSF WBC ≥10, urinalysis >10 WBC or positive dip.
• Modified Philadelphia criteria: peripheral WBC ≥15,000, CSF WBC ≥8, positive CSF Gram-stain, urinalysis >10 WBC or positive dip.

Main Results:

• Modified Boston criteria (n=8344) had 62.7% sensitivity and 59.2% specificity for IBI.
• Modified Philadelphia criteria (n=8131) had 71.7% sensitivity and 46.1% specificity for IBI.
• Both criteria misclassified a significant proportion of infants with bacterial meningitis (32.1% and 23.3%, respectively).

Conclusions:

• Modified Boston and Philadelphia criteria demonstrate suboptimal performance in identifying invasive bacterial infections in infants aged 29-60 days.
• These criteria misclassify a substantial number of infants, including those with serious conditions like bacterial meningitis.
• Revising diagnostic guidelines may be necessary to improve the accurate identification of serious bacterial infections in this age group.