Invasive bacterial infections in afebrile infants diagnosed with acute otitis media

OBJECTIVES: To determine the prevalence of invasive bacterial infections (IBIs) and adverse events in afebrile infants with acute otitis media (AOM). METHODS: We conducted a 33-site cross-sectional study of afebrile infants #90 days of age with AOM seen in emergency departments from 2007 to 2017. Eligible infants were identified using emergency department diagnosis codes and confirmed by chart review. IBIs (bacteremia and meningitis) were determined by the growth of pathogenic bacteria in blood or cerebrospinal fluid (CSF) culture. Adverse events were defined as substantial complications resulting from or potentially associated with AOM. We used generalized linear mixed-effects models to identify factors associated with IBI diagnostic testing, controlling for site-level clustering effect. RESULTS: Of 5270 infants screened, 1637 met study criteria. None of the 278 (0%; 95% confidence interval [CI]: 0%-1.4%) infants with blood cultures had bacteremia; 0 of 102 (0%; 95% CI: 0%-3.6%) with CSF cultures had bacterial meningitis; 2 of 645 (0.3%; 95% CI: 0.1%-1.1%) infants with 30-day follow-up had adverse events, including lymphadenitis (1) and culture-negative sepsis (1). Diagnostic testing for IBI varied across sites and by age; overall, 278 (17.0%) had blood cultures, and 102 (6.2%) had CSF cultures obtained. Compared with infants 0 to 28 days old, older infants were less likely to have blood cultures (P, .001) or CSF cultures (P, .001) obtained. CONCLUSION: Afebrile infants with clinician-diagnosed AOM have a low prevalence of IBIs and adverse events; therefore, outpatient management without diagnostic testing may be reasonable.