Evaluation of Hematological Indices, Their Longitudinal Trends, and Association With Stratified Dengue Severity in Pediatric Cohorts: A Prospective Observational Study.

BACKGROUND: Dengue fever is a widely prevalent viral disease, with one of the most common laboratory findings being thrombocytopenia. Although platelet indices like mean platelet volume (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR), and plateletcrit (PCT) are routinely measured, their utility in clinical practice has been limited. This study was planned to evaluate platelet indices across the range of disease severity, understand their importance in terms of their trends over the disease course, and correlate them with other hematological parameters in pediatric dengue. METHODS: A prospective observational study was carried out on a sample of 55 children aged 0-18 years diagnosed with dengue fever in the inpatient pediatrics department. Data regarding clinical features, hematological parameters, including platelet indices, and other laboratory parameters over a period of three days were collected. RESULTS: A total of 27 (49%) study participants had dengue without warning signs (DF-1), 20 (36.3%) had dengue with warning signs (DF-2), and eight (14.5%) had severe dengue (DF-3). Significantly rising trends of MPV and PDW were observed in the DF-1 group, contrasting with a falling MPV and P-LCR among participants with severe dengue (DF-3). Moreover, PDW and P-LCR exhibited significant negative correlation with platelet count and PCT values, with MPV showing a significant but weak positive correlation with hematocrit. CONCLUSION: Monitoring platelet index trends over the disease course, in conjunction with other parameters, can serve as an indirect indicator of the bone marrow response to thrombocytopenia. Falling trends of MPV, PDW, and P-LCR with low platelet counts could suggest a deteriorating patient course and may warrant more vigilant monitoring.