Association between serum vitamin-D levels and severity of dengue fever in children: A cross-sectional study

Objectives: Dengue fever is a prevalent viral disease transmitted by mosquitoes, with clinical presentations varying from mild fever to serious, life-threatening conditions. Although Vit D is recognised for its vital role in immune system regulation, its influence on the severity of dengue infection in paediatric patients remains inadequately understood. This study aims to measure serum Vitamin-D levels in children aged between 1 and 15 years diagnosed with dengue fever and to examine the association between Vitamin-D status and the severity of the illness. Material and Methods: A hospital-based cross-sectional study was conducted involving 100 children confirmed to have dengue infection through laboratory tests. The severity of the disease was classified according to the 2009 World Health Organization guidelines into three categories: Dengue without warning signs, dengue with warning signs and severe dengue. Serum concentrations of 25-hydroxyVit-D were determined utilising a chemiluminescent immunoassay technique. Results: There was a significant decline in mean serum Vit-D levels as the severity of dengue increased, with levels averaging 28.5 ± 6.8 ng/mL in mild cases compared to 15.8 ± 4.9 ng/mL in severe cases ( p = 0.001). Vit-D deficiency, defined as levels below 20 ng/mL, was found in 80% of severe dengue cases versus 10% of mild cases ( p = 0.001). Furthermore, serum Vit-D had a positive correlation with platelet counts ( r = 0.643, p = 0.001) and a negative correlation with haematocrit levels ( r = −0.543, p = 0.002). Conclusion: Vitamin-D deficiency was significantly associated with increased severity of dengue fever in children. Regular assessment and correction of Vitamin-D levels may help in forecasting disease progression and could be integrated as part of the therapeutic strategy in managing dengue illness.