Calc Function

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    • Subcategory of 'Diagnosis' designed to be very sensitiveRule Out
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    Chief Complaint


    Organ System


    Patent Pending

    Rochester Criteria for Febrile Infants

    Determines whether febrile infants are low risk for serious bacterial infection.


    Use in febrile infants ≤60 days of age (rectal temp ≥38°C or 100.4°F).

    When to Use
    Why Use
    • Well-appearing infants ≤60 days old presenting to the emergency department for a chief complaint of fever ≥38ºC (100.4ºF), or found to have fever on presentation for other complaint.
    • Ill-appearing infants should be redirected to sepsis guidelines.
    • While the validation study looked at infants any age ≤60 days, in clinical practice infants <28 days are often considered NOT low risk due to age.
    • Premature infants should be assessed based on corrected age (e.g. for infant born at 30 weeks gestational age, subtract 7 weeks from chronologic age).
    • Identifies infants at low risk for serious bacterial infection (SBI), defined as bacteremia, meningitis, osteomyelitis, suppurative arthritis, soft tissue infections (cellulitis, abscess, mastitis, omphalitis), urinary tract infection, gastroenteritis, or pneumonia.
    • Infants ≤60 days may present with minimal signs and symptoms, or appear similarly to those with viral infection. The criteria can help identify SBI; prevalence is 10-12% in this group, with the majority (>90%) representing UTI (Biondi et al 2013, Greenhow et al 2014)
    • May reduce over-testing and treatment of well-appearing febrile infants.

    Diagnostic Result:

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    • Herpes simplex virus (HSV) risk factors should be carefully assessed, including: maternal history of HSV infection or primary lesions at delivery, household contacts with lesions, vesicular rash, presentation with seizures, or pleocytosis on cerebrospinal fluid (CSF) testing.
    • Positive viral testing (e.g. RSV, influenza) reduces serious bacterial infection (SBI) likelihood by ~50%, but the risk of concurrent SBI is NOT zero (Greenhow 2014, Krief 2009).
    • The gold standard for urine culture is a sample obtained via straight catheterization. “Bag” urine introduces risk of specimen contamination with skin flora.
    • Obtain blood, urine, and CSF samples BEFORE starting antibiotics, if possible.
    • Differential diagnosis of ill-appearing infants <60 days of age should also include the following: congenital heart disease, metabolic disease (e.g. galactosemia), congenital adrenal hyperplasia with adrenal crisis, and non-accidental trauma.


    If LOW risk (in the derivation study, SBI occurred in 1% of low risk infants):

    • Limited testing, including complete blood count, blood culture, urinalysis, and urine culture, is recommended.
    • These infants generally do not require antibiotics.
    • Generally safe to be discharged home, given no social concerns or question of ability to follow up with their primary care provider (PCP).

    If NOT low risk (in the study, SBI occurred in 12.3% of infants not at low risk):

    • Further testing is required, including complete blood count, blood culture, urinalysis, urine culture, and cerebrospinal fluid (CSF) testing.
    • Empiric broad spectrum antibiotic coverage is indicated.
    • Admission is recommended, pending negative cultures at 24-36 hours.
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