The aim of this study was to investigate the pro-oxidant and proinflammatory biomarkers and their relationship with dimethylarginines (DMAs) in patients at various stages of chronic kidney disease (CKD). We studied 114 CKD patients, 36 were hemodialyzed, 41 peritoneal dialyzed and 37 nondialyzed (early stage) CKD patients. The control group consisted of 31 healthy subjects. Plasma levels of asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), l-arginine, nitric oxide (NO) and proinflammatory cytokines (TNF-alpha and IL-6) were determined, and their relationships with the degree of disease were evaluated. Both DMAs were at high levels in all CKD patients, whereas arginine concentrations were low in patients undergoing dialysis. Elevated TNF-alpha and IL-6 in CKD patients were indicative of ongoing chronic inflammatory state. A significant positive correlation between SDMA and creatinine suggests that plasma SDMA level may be an index for renal function.