SGEM#501: Here it Goes Again – Another Clinical Decision Rule for Febrile Infants 61-90 Days

Reference: Aronson PL, et al. Prediction Rule to Identify Febrile Infants 61–90 Days at Low Risk for Invasive Bacterial Infections. Pediatrics. September 2025 Date: January 6, 2026 Dr. Jillian Nickerson Guest Skeptic: Dr. Jillian Nickerson is a pediatric emergency medicine attending at Children’s National Hospital and Assistant Professor of Pediatrics and Emergency Medicine at The George Washington University School of Medicine and Health Sciences in Washington, DC. Prior to completing her PEM fellowship, she completed an emergency medicine residency at Mount Sinai in New York. Now she is also the associate program director for the pediatric emergency medicine fellowship program at Children’s National Hospital. Background: Fever is a common complaint that we encounter in the emergency department. In general, we want to be careful in our counseling and our practice not to perpetuate many of the myths and misconceptions that contribute to fever phobia. But there are certain populations where fever does get us a bit worried. When infants present with fever, we have to think about evaluating for other sources of infection such as bacteremia or meningitis, termed invasive bacterial infections (IBI). Fortunately, the prevalence of IBI tends to be low, but missing one could lead to significant morbidity or mortality. How do we determine whom to test and what tests to perform? We’ve covered multiple clinical decision rules for risk-stratifying febrile infants before on the SGEM: SGEM #171: Step-by-Step Approach to the Febrile Infant SGEM#296: She’s Got the Fever but Does She Need an LP, Antibiotics or an Admission? SGEM#341: Are the AAP Guidelines for the Evaluation and Management of the Well-Appearing Febrile Infant SGEM#387: Lumbar Punctures in Febrile Infants with Positive Urinalysis SGEM #474: Help! Which Clinical Decision Aid Should I Use to Risk Stratify Febrile Infants? Some of these clinical decision rules like Step by Step can be applied to infants up to 90 days. Others like the 2021 American Academy of Pediatrics (AAP) clinical practice guideline and the Pediatric Emergency Care Applied Research Network (PECARN) clinical decision rule, only include infants up to 60 days. Clinical Question: Is there an accurate prediction rule to identify well-appearing febrile infants 61–90 days old who are at low risk for invasive bacterial infection (IBI)? Reference: Aronson PL, et al. Prediction Rule to Identify Febrile Infants 61–90 Days at Low Risk for Invasive Bacterial Infections. Pediatrics. September 2025 Population: Non-ill-appearing febrile infants 61–90 days who had evaluation with both urinalysis/urine dipstick and blood culture Excluded: infants who were critically ill (ESI level 1, intubated, received vasoactive medication), death in the ED, prematurity ?32 weeks, substantial pre-existing medical or surgical conditions, skin or soft tissue infections, home antibiotic use before ED visit Intervention: Derivation