Comparison of plasma creatinine determined with the greiner selective analyser GSA II and the glomerular filtration rate

1. Reference values for the plasma creatinine were established using the alkaline picrate method with the Greiner Selective Analyzer GSA II in relation to the Cr 51-EDTA Clearance. Individuals with normal GFR between 93 to 159 ml/min/1.73 m2 had creatinine values in men (n = 65) from 53.7 to 119.5 mumol/l (0.61 to 1.35 mg/100 ml) and in women (n = 59) from 37.7 to 107 mumol/l (0.42 to 121 mg/100 ml). 2. The creatine determinations with the GSA II were compared to those on the Technicon Analyzer, the Beckman Creatinine Analyzer, the Gemsaec-Fast Analyzer and to the enzymatic creatinine method. A good correlation (r = 0.9780-0.984) was observed. 3. With the GSA II and the enzymatic method, bilirubin showed a minor interference which was more marked with the Beckman analyzer.