Systematic review and meta-analysis of circulating microRNAs in dengue infection: biomarkers, pathogenesis, and clinical implications.

Dengue infection is a mosquito-borne disease that can cause mild illness or severe haemorrhagic fever. Predictive biomarkers for severe cases, especially those with bleeding manifestations or plasma leakage, are currently lacking. This systematic review and meta-analysis synthesises findings from studies on circulating miRNAs in dengue infection, sourced from PubMed, Scopus, Science Direct, and Web of Science, with quality assessed by the Newcastle-Ottawa Scale (PROSPERO: CRD42024521685). Quantitative meta-analyses were conducted using RStudio to evaluate diagnostic Area Under the Curve (AUC) metrics across five eligible studies and Standardised Mean Differences (SMD) for differential miRNA expression. Key miRNAs, such as miR-146a, miR-150, miR-378, miR-21-5p, and miR-1246, were found to regulate immune responses, inflammation, and viral replication. Meta-analysis demonstrated high overall diagnostic accuracy for circulating miRNAs, with individual reported AUC values ranging from 0.79 to 1.00; however, substantial statistical heterogeneity was observed across pooled metrics (I-squared exceeding 89%). SMD analysis highlighted significant upregulation of acute inflammatory drivers, including miR-21-5p (SMD = 4.67) and miR-450b-5p (SMD = 6.76), alongside marked downregulation of endothelial-protective markers such as miR-126-3p (SMD = -1.31). Rather than viewing dysregulated microRNAs as a uniform class of clinical tools, this review highlights that candidate microRNAs span distinct translational tiers. Recognising these validation levels alongside pre-analytical and biological heterogeneity is essential for prioritising the most viable microRNA candidates for future prospective clinical translation and targeted therapies in dengue management.