Elevated plasma advanced oxidation protein products in children with Henoch–Schonlein purpura

Henoch–Schonlein purpura (HSP) is a systemic vasculitis characterized by involvement of skin, joints, gastrointestinal tract (GIT), and kidney; its pathogenesis is still controversial. The aim of our study was to investigate the role of oxidative stress in the pathogenesis of HSP. Plasma advanced oxidation protein products (AOPP) level was measured in 29 children with HSP at the onset of the disease and during remission in comparison with 30 healthy subjects. Patients at the active stage had significantly higher AOPP levels than those at the remission stage of HSP and the controls (42.9 ± 25.7, 30.6 ± 11.8, 27.9 ± 11.2 mmol/l; P = 0.027 and P = 0.023 respectively). The mean AOPP levels of the patients with arthritis and/or arthralgia were significantly higher those than without joint involvement (48.3 ± 26.0 and 22.3 ± 9.3, P = 0.036 respectively). However, AOPP levels were similar in patients with and without gastrointestinal involvement. Plasma AOPP levels were positively correlated with leukocyte and thrombocyte count at disease onset, whereas they were found to be negatively correlated with serum glucose and sodium levels. The mean thrombocyte count was the only independent predictor of increased level of AOPP in regression analysis (β = 0.407; P = 0.029). In conclusion, this study showed that increased oxidative stress may play an important role in the pathogenesis of HSP. Also, we suggest that higher platelet count might be an indirect indicator of oxidative stress in these patients. Further research is required to identify the potential association between oxidative stress and increased thrombocyte count in children with HSP.