Elevated levels of vascular endothelial growth factor in adults with severe dengue infection

The immune pathogenesis of dengue involves antibody production, B cell and T cell response and various pro-inflammatory and anti-inflammatory cytokines. VEGF, a potent permeability enhancing cytokine, is thought to play a pivotal role in mediating plasma leakage in DHF. It is a member of growing family of related proteins that includes VEGF B, VEGF C, VEGF D and placental growth factor. It promotes angiogenesis and vascular integrity. In addition to its role in promoting endothelial permeability & proliferation, it may contribute to inflammation and coagulation. This study was undertaken to investigate the role of VEGF in the patients with dengue infection. Sera were collected from 106 patients with various grades of dengue illness and 40 healthy controls and tested for VEGF levels using commercial ELISA kits. Viral serotypes were detected using specific primers. The results showed very low levels of VEGF (3.493 ± 1.982 pg/ml) in healthy controls. Levels of VEGF were higher in patients with severe dengue (428.170 ± 224.61 pg/ml) as compared to patients with non severe dengue with and without warning signs (290.407 ± 167.17 pg/ml). Significant correlation (p < 0.001) was found between raised VEGF levels and thrombocytopenia and raised haematocrit levels. The VEGF profile patterns discovered between the different phases of illness indicate an essential role in dengue pathogenesis and with further studies may serve as predictive markers for progression of dengue fever to severe dengue infection.