مرکز منطقه ای اطلاع رساني علوم و فناوري - Evaluation of Nine Analytes Stability and Determination of Their Signifi cant Variability Limits in Human Plasma and Serum Samples

Abstract :

Laboratory studies related to preanalytical variability are still of great importance all over the world. Separation of serum and plasma from blood cells as soon as possible is very important for the reliability of results obtained. The most suitable temparatures are 4°C or -20°C if the sample will not be used immediately. In this study we determined changes in the stability of 9 plasma and serum analytes (glucose, potassium, phosphorus, AST, ALT, albumin, triglyceride, total protein, total cholesterol) in plasma and serum after the centrifugation of sample in normal and extended time at in room temperature (25-28° C). In addition, we observed effects of the change in the stability of these analytes on clinical evaluation. In conclusion we found out that there were signifi cant clinical differences in the stability of glucose, potasium and phosphorus in samples obtained after 24 hours (according to CLIA 88 criteria). Signifi cant changes in glucose, potasium and phosphorus were observed in the 6th, 24th and 24th hours respectively. It was found out that stability of these three parameters were very weak. There was no signifi cant difference, which can affect the clinical evaluation, in the samples separated immediately for these parameters. This means that the prompt separation of serum or plasma from blood cells is quite important for the reliability of results. We also think that parameters which make difference statistically but do not display clinical difference need more careful handling.