Patient selection: fever (>= 38°C at home or in ED) without source in an infant less than 3 months old
Outcome: serious bacterial infection (SBI)
Percent of infants with positive blood cultures: 2.2%
Percent of infants with positive blood cultures who are low risk for SBI: 0.6%
Percent of infants with positive blood cultures with evidence of UTI: 4.4%
The authors recommended blood cultures in these patients especially if:
(1) the patient does not look well
(2) the patient has leukocyturia and/or nitrituria
The study was performed prior to availability of procalcitonin.
Criteria for low risk for serious bloodstream infection (SBI):
(1) previously healthy
(2) well-appearing
(3) urine without leukocyturia and without nitrituria
(4) WBC count from 5,000 to 15,000 per µL
(5) absolute neutrophil count < 10,000 per µL
(6) no pleocytosis in CSF if lumbar puncture performed
(7) normal evaluation during several hours under observation
