Clinical Fellow Boston Children's Hospital Boston Children's Hospital Department of Pediatrics Boston, Massachusetts, United States
Background: Clinicians often observe febrile children in the ED after antipyretic and use defervescence as a criterion for safe discharge. There is a widespread belief that children with bacterial infections are less likely to defervesce than children without bacterial infections.
Objective: The objective of this study was to determine whether lack of response to antipyretics was associated with bacteremia.
Design/Methods: Cross-sectional study of febrile (T≥38.0 Celsius) children who presented to a single tertiary care pediatric emergency department from 2012 to 2020 and had a blood culture obtained. We included all children who received an antipyretic within 60 minutes of triage and had a temperature re-check within 4 hours of triage. We assessed the association between defervescence at various time intervals (60, 90, 120, 180, and 240 minutes after antipyresis) and bacteremia adjusting for age, complex chronic condition, blood culture source (central venous line versus peripheral), specific antipyretic initially administered, time of day, and height of triage temperature.
Results: A total of 242 of 6319 febrile children (3.8%) had growth of a pathogen in blood culture (Table 1). Patients with a pathogen detection in blood culture were more likely to be older, have a complex chronic condition, and to be hospitalized. Of the 6319 children included, 5621 (89.0%) remained febrile 60 minutes following antipyretic administration, 4541 (71.9%) at 90 min, 3183 (49.7%) at 120 minutes, 1481 (23.4%) at 180 minutes, and 904 (14.3%) at 240 minutes after antipyresis. In the multivariable model, the aOR of a positive blood culture was 1.6 (1.2-2.2) among children who remained febrile at 180 minutes and 1.7 (1.2-2.4) among children who remained febrile at 240 minutes (Table 2). The positive likelihood ratio of bacteremia was 1.4 for children who remained febrile at 3 hours (positive predictive value 5.2%), and 1.7 for children remaining febrile for 4 hours (positive predictive value 6.2%). Conclusion(s): In febrile children presenting to the emergency department, response to antipyretics can be used to risk-stratify children for risk of bacteremia.
Table 1. Demographic characteristics of patients who presented febrile and had blood cultures sent
Table 2. Association between time after antipyretic patient became afebrile and blood culture results
Authors/Institutions: Alexandra H. Baker, Boston Children's Hospital Department of Pediatrics, Boston, Massachusetts, United States; Michael Monuteaux, Boston Children's Hospital, Boston, Massachusetts, United States; Kenneth Michelson, Boston Children's Hospital, Boston, Massachusetts, United States; Mark Neuman, Boston Children's Hospital, Boston, Massachusetts, United States