Oxidative stress status in familial Mediterranean fever with or without proteinuria.

Although several studies have indicated oxidative system abnormalities in patients with familial Mediterranean fever, it is still obscure whether proteinuria seen in this disease has an effect on the oxidative system. In the present study, oxidative system changes were investigated in familial Mediterranean fever with or without proteinuria. Plasma malondialdehyde levels in proteinuric and nonproteinuric patients were higher than those of the controls and they were also significantly higher in the patients with proteinuria compared to patients without proteinuria. The patients had significantly lower plasma glutathione peroxidase activities than the controls. Glutathione peroxidase activities did not show statistically significant differences between the patients with and those without proteinuria. A significant difference was not established for erythrocyte superoxide dismutase activities. These data suggest that there is an increase in lipid peroxidation in familial Mediterranean fever. Decreased plasma glutathione peroxidase activities seem to be responsible for increased plasma malondialdehyde levels in both patient groups. However, the fact that higher plasma malondialdehyde levels in proteinuric patients were observed compared to nonproteinuric patients in the presence of the unchanged plasma glutathione peroxidase activities in these groups suggests that the nephrotic state may have a contribution to this situation.