Objective: This scoping review aims to assess the evidence regarding miRNA associations with paediatric bacterial and viral infections. Introduction: Febrile children present a challenge in emergency care, often leading to unnecessary antibiotics due to difficulty distinguishing bacterial from viral infections. Current biomarkers lack specificity, contributing to diagnostic uncertainty and antimicrobial resistance. MicroRNAs (miRNAs), detectable in blood and responsive to disease, show promise as improved biomarkers, but their role in infection differentiation remains unclear. This scoping review aims to map known miRNA associations with paediatric infections and evaluates study methodologies to identify the best approaches for miRNA-based diagnostics. Inclusion criteria: Studies reporting on children under 18 years of age with acute bacterial or viral infections will be included. Articles must focus on host miRNA biomarkers in biofluids. Exclusions include chronic infections, parasitic infections, fungal infections, sexually transmitted infections, animal models, in vitro, tissue samples, and in silico studies. Methods: The databases to be searched will include MEDLINE and Web of Science with an additional for grey literature search via Google, Google Scholar, and open Theses restricted to the English language. Titles and abstracts will be screened, and eligible articles will undergo full-text review. The results of the search and study inclusion/exclusion process will be reported. Reasons for exclusion during the full text review are presented in the PRISMA-ScR flow diagram. Data will be extracted into a chart, analysed as percentages to assess consensus, and summarized in descriptive text with tables.

The authors have declared no competing interest.

This study has been supported by the Department for the Economy (Northern Ireland).

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The study will use ONLY openly available human data accessed via MEDLINE or Web of Science.

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