Febrile Infant Clinical Pathway — Emergency Department and Inpatient

Inclusion Criteria

0 to 56 days of age
Recorded temp ≥ 38.0° C (100.4° F) in past 24 hrs
Well-appearing

The following infants may have higher risk of invasive bacterial infection. IMs alone should not be used for risk stratification:
- Premature birth < 37 wks gestation
- Prolonged N/IICU stay
- Complex Medical History
- Physical Exam with Concern for Focal Bacterial Infection

Lab Study	Definition of Abnormal
Procalcitonin	> 0.5 ng/mL
Absolute Neutrophil Count	> 4000 neutrophils/µL
Urinalysis with Reflex to Microscopy	Any leukocyte esterase (LE) on dipstick or > 5 WBCs per hpf
CSF	0-28 days: ≥ 15 WBC/µL 29-56 days: ≥ 9 WBC/µL

Antimicrobials: Recommendations, Dosing, and Rationale

ED Triage
ED nursing pathway standing
order set: Febrile Young Infant

ED Team Assessment and
Bedside Procedure
History and Physical
IV and Laboratory Studies
POC glucose as needed
Consider HSV and Other
Diagnostic Testing
If 0-21 days old: LMX to LP site,
LP tray at bedside

Ill-appearing or as clinically indicated:
- Sepsis Huddle
- Sepsis Pathway
  - Sepsis N/IICU
  - Sepsis ED,
    Inpatient, PICU

Summary of Pathway Updates
Adapted from AAP Guidelines 2021

Infants 0-21 Days Old

Blood culture
UA, urine culture
HSV Testing
Perform LP

CBC, blood culture
Inflammatory Markers (IMs): Procalcitonin, ANC
UA, urine culture
Consider HSV Testing

Abnormal UA
- or
≥ 1 abnormal IM
Perform LP

Normal UA
Normal IMs
No LP

Infants 22-28 Days Old

Infants 29-56 Days Old

CBC, blood culture
Inflammatory Markers (IMs): Procalcitonin, ANC
UA, urine culture
Consider HSV Testing

Infants with
Bronchiolitis

Normal UA
≥ 1 abnormal IM
Perform LP

Abnormal UA
Abnormal IMs
LP Guidance

Abnormal UA
Normal IMs
No LP

Normal UA
Normal IMs
No LP

Antimicrobials

No antimicrobials

Antimicrobials

Antimicrobials

Discharge home w/follow-up
or
Admit w/o antimicrobials as indicated for etiologies other than serious bacterial infections

Admit from Emergency Department

LP Indicated, but No CSF Obtained

Any Positive Culture or HSV PCR

Discharge Criteria

Posted: August 2010
Last Revised: March 2025

Authors:
- R. Scarfone, MD;
- P. Gala, MD;
- L. Sartori, MD;
- B. Ku, MD;
- J. Lavelle, MD;
- MK. Abbadessa, ACCNS-P;
- L. Bell, MD;
- E. Kane, MD;
- E. Kahle, MD;
- C. Jacobstein, MD;
- K. Chiotos, MD;
- T. Metjian, PharmD;
- J. Kelly, MD

Editors: Clinical Pathways Team

Evidence

Educational Media

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The clinical pathways are based upon publicly available medical evidence and/or a consensus of medical practitioners at The Children’s Hospital of Philadelphia (“CHOP”) and are current at the time of publication. These clinical pathways are intended to be a guide for practitioners and may need to be adapted for each specific patient based on the practitioner’s professional judgment, consideration of any unique circumstances, the needs of each patient and their family, and/or the availability of various resources at the health care institution where the patient is located.

Accordingly, these clinical pathways are not intended to constitute medical advice or treatment, or to create a doctor-patient relationship between/among The Children’s Hospital of Philadelphia (“CHOP”), its physicians and the individual patients in question. CHOP does not represent or warrant that the clinical pathways are in every respect accurate or complete, or that one or more of them apply to a particular patient or medical condition. CHOP is not responsible for any errors or omissions in the clinical pathways, or for any outcomes a patient might experience where a clinician consulted one or more such pathways in connection with providing care for that patient.