A simple clinical decision rule may help to rule out severe bacterial infection and spare antibiotics in febrile young children.

Aim: To assess the performance of a new clinical decision rule (CDR) to identify patients at a low risk of invasive bacterial infection (IBI) among febrile children and its theoretical impact on antibiotic use.

Methods: Prospective study including consecutive children <5 years of age who presented in one French paediatric emergency department with fever without source between January and December 2016. With the collected data, we constructed a CDR based on a sequential approach based on age, clinical toxic signs, urinalysis and procalcitonin level. We evaluated its diagnostic performances to identify IBI and its potential impact on antibiotic use.

Results: Among the 1061 children (IBI 11/1061, 1.0%), 693 (65.3%) were classified at low or intermediate risk of IBI, with an IBI prevalence of 0%. The sensitivity and specificity of the CDR to predict IBI were 100% and 73.9%. Negative and positive predictive value were 100% and 3.9%, respectively. Using this new CDR, the current antibiotics exposure would theoretically be reduced from 33.6% to 24.1%.

Conclusion: The promising interest of this clinical decision rule, using simple and accessible biological and clinical tools, needs to be confirm with an external validation study, which will allow its use in clinical practice.