Creatinine concentration measurement in glucose based peritoneal dialysate

The measurement of creatinine concentrations in peritoneal dialysate is important for evaluating the effectiveness of peritoneal dialysis treatment. However, peritoneal dialysate often contains glucose, which has been reported to interfere with the measurement of creatinine concentrations in some creatinine assays. In this study creatinine concentrations in solutions containing increasing glucose concentrations (0-250 mmol/L) were evaluated using an enzymatic method. No relevant interference from glucose was observed. The creatinine concentration recovery percentages at creatinine concentrations of 250, 500, and 750 micromol/L in dialysate samples containing 250 mmol/L glucose were 101.9%, 101.6%, and 101.0%, respectively, and 101.64%, 102.2%, and 99.8%, in water samples (0 mmol/L glucose). The measured creatinine concentrations in dialysate samples at constant glucose concentrations were linear at 0-1071 micromol/L creatinine, and the linear regression coefficient was 0.99. It is concluded that the enzymatic method described is reliable in measuring creatinine concentrations in dialysate containing glucose, and that the method can be used to evaluate the effectiveness of peritoneal dialysis treatment.