Acute Respiratory Distress Syndrome (ARDS) is a severe inflammatory lung condition that leads to respiratory failure, posing high morbidity and mortality risks, especially in critically ill patients. The current diagnostic criteria, based on clinical presentation and imaging findings, often result in delayed recognition. In recent years, numerous biomarkers have emerged with the potential to detect ARDS in its early stages, improving both diagnosis and treatment outcomes. This comprehensive narrative review explores the biological significance and clinical relevance of various biomarkers—including surfactant proteins, inflammatory mediators, endothelial and epithelial injury markers, coagulation-related factors, and genetic indicators like microRNAs—in the early diagnosis of ARDS. It also discusses their diagnostic performance, the limitations of current studies, and future perspectives on integrating biomarkers into clinical practice. The goal is to provide a deeper understanding of how these molecular tools can shift ARDS diagnosis from a reactive to a proactive approach.

KEYWORDS
ARDS, Acute Respiratory Distress Syndrome, Biomarkers, Early Diagnosis, SP-D, sRAGE, CC16, IL-8, MicroRNA, Inflammatory Markers, Lung Injury, Hypoxemia, Precision Medicine, Prognosis, Ventilator-Associated Lung Injury