Background: Dengue can cause increased vascular permeability that may lead to hypovolemic shock. Endothelial dysfunction may underlie this; however, the association of endothelial nitric oxide (NO) pathways with disease severity is unknown.
Methods: We performed a prospective observational study in 2 Vietnamese hospitals, assessing patients presenting early (<72 hours of fever) and patients hospitalized with warning signs or severe dengue.