Association between glutathione peroxidase levels and clinical manifestations of dengueBackground: Glutathione peroxidase (GP) can be used as a marker of oxidative stress in infectious diseases.Aim: To evaluate the association between the levels of glutathione peroxidase (GP) and the manifestations and complications of dengue.Patients and Methods: Between April 2003 and December 2004, 161 patients with dengue were prospectively evaluated.In the first evaluation, within 48 and 96 hours of disease onset, a plasma sample was obtained to measure the GP levels.The association between GP levels, clinical manifestations and complications was evaluated during the follow up.Results: Mean GP values were 1198 U/L (95% confidence interval 1089-1306).Values greater than 1200 U/L were associated with headache, arthralgias and increased heart rate.There was a negative association between GP levels and serum triglycerides.During follow up, patients with GP >1200 U/L had a higher frequency of spontaneous hemorrhages.In a logistic regression analysis arthralgias, fever and increased heart rate, were independently associated with levels >1200 U/L.Conclusions: GP levels was associated to some of the manifestations of dengue.This finding suggests that the intensity of oxidative stress can influence the clinical presentation of dengue (Rev Méd Chile 2007;