Platelet Indices as Biomarkers of Disease Severity and Morbidity in Hospitalized Dengue Patients

Abstract Background: Dengue fever is a rapidly expanding mosquito-borne illness with significant morbidity in children. While thrombocytopenia is a key feature, platelet count alone poorly predicts disease severity. Platelet indices such as mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) may provide better insight into disease progression and complications. Materials and Methods: This hospital-based cross-sectional observational study was conducted in the Department of Pediatrics, at a tertiary care hospital over 18 months. A total of 120 children aged 1–16 years with confirmed dengue infection (NS1 antigen or immunoglobulin M positive) were enrolled. Platelet indices were recorded at admission. Patients were classified according to the World Health Organization 2009 dengue severity criteria. Associations between platelet indices and disease severity, hepatic dysfunction, and renal dysfunction were analyzed using appropriate statistical tests. Results: Among 120 patients, 35% had dengue without warning signs, 48.3% had warning signs, and 16.7% had severe dengue. MPV and PCT decreased, while PDW increased significantly with disease severity ( P < 0.001). Hepatic (31.7%) and renal (9.2%) dysfunction were associated with lower MPV and PCT and higher PDW ( P < 0.001). PDW showed a strong positive correlation with severity ( r = 0.71), whereas MPV and PCT showed negative correlations. Conclusion: Platelet indices, particularly PDW and PCT, are simple, readily available, and reliable markers for predicting disease severity and organ dysfunction in pediatric dengue. Their routine use may aid early risk stratification, timely intervention, and improved clinical decision-making, especially in resource-limited settings where advanced biomarkers may not be accessible.