Evaluation of a New Diagnostic Kit for the Enzymatic Determination of Creatinine

We have evaluated a new diagnostic kit for the enzymatic determination of creatinine in serum, plasma and urine. The method was found to be linear up to 1000 mumol/l. Within-run precision had a coefficient of variation of 3.1--5.6% for normal to slightly elevated values and of 2.3--3.3% for values of about 320 mumol/l. Day-to-day precision was found to be 7.8 and 5.7% for values of 94 and 141 mumol/l, respectively. Mean analytic recovery was 98%. Bilirubin and hemoglobin did not interfere in concentrations up to 490 and 240 mumol/l, respectively. The influence of lipids was studied. Correlation studies were done with two other methods, the Technicon SMA 12/60 method and the Dutch standard manual method.