Is plasma symmetric dimethylarginine a suitable marker of renal function in children and adolescents?

Objective. The purpose of this cross-sectional study was to identify whether plasma symmetric dimethylarginine (pSDMA) is a useful marker of renal function in children. Material and methods. The study group consisted of 35 patients with chronic kidney disease (CKD) stages 1-5 (median age 11.5 years), classified on the basis of estimated glomerular filtration rate (eGFR) and divided into three groups: group A, patients with CKD stages 1 and 2; group B, CKD stage 3; and group C, CKD stages 4 and 5. A control group included 42 age-matched healthy children. Commercial enzyme-linked immunosorbent assay kits were used to measure pSDMA and serum cystatin C (sCysC) concentrations. Results. The pSDMA and sCysC levels were significantly elevated in all CKD patients in comparison with healthy controls (p < 0.05). The pSDMA level in children was increased in the mild CKD (group A) (p < 0.01). There were also a significant difference in pSDMA concentration between groups A and B (p < 0.01). No differences in pSDMA levels were found between groups B and C. Receiver operating characteristics analyses showed that pSDMA was a better diagnostic tool than sCysC for identifying CKD stage among all the examined children and for detecting patients from group A (eGFR >60 ml/min/1.73 m(2)). Conclusions. Increased pSDMA and sCysC levels were found in CKD children. Further studies are required to confirm potential applications of pSDMA and CysC as useful biomarkers for the diagnosis and progression of CKD.