The Effect of Delay in Serum Separation on the Results of Biochemical Tests

Document Type : Original Article(s)

Authors

1 BS in Medical Laboratory Science, Treatment Management of Social Security Organization of Kohgiluyeh and Boyer-Ahmad Province, Yasouj, Iran

2 MSc in Clinical Biochemistry, Medicinal Plants Research Center, Yasuj University of Medical Sciences, Yasuj, Iran

3 MSc in Medical Virology, Treatment Management of Social Security Organization of Kohgiluyeh and Boyer-Ahmad Province, Yasouj, Iran

4 Professor, Medicinal Plants Research Center, Yasuj University of Medical Sciences, Yasuj, Iran

5 MSc in Medical Immunology, Legal Medicine Research Center, Legal Medicine Organization, Yasouj, Iran

Abstract

Background: The present study aimed to investigate the impact of delayed serum separation on the results of some biochemical tests, as one of the pre-analytical errors.
Methods: In this study, 50 healthy volunteers participated. 12 ml of blood was taken from each person and divided into 6 assigned tubes. In order to separate the serum, one sample from each participant was centrifuged as a base sample at the standard time (1 hour after blood sampling), the remaining samples from each participant were centrifuged with delay of 1,2,3,4 and 5 hours compared to the base sample. The serum from each sample was analyzed for 21 different analytes including blood sugar (BS), blood urea nitrogen (BUN), uric acid (U.A), calcium (Ca), magnesium (Mg), triglyceride (TG), cholesterol (Chol), high-density lipoprotein (HDL), aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), total bilirubin (T.B), direct bilirubin (D.B), albumin (Alb), total protein (TP), amylase (Amy), lipase (Lip), lactate dehydrogenase (LDH) and creatine phosphokinase (CPK).
Findings: A significant difference was found in the mean blood sugar (BS) levels in the elapsed times from the time of blood sampling. The means of BS showed a decrease of 4.78 % on average for each hour of delay in serum separation. In the case of other analytes, no significant difference was observed between their means at each of the time points elapsed since the time of blood sampling.
Conclusion: Considering the significant effect of delay in serum separation on the BS test, it is necessary to centrifuge the whole blood sample and separate its serum as soon as possible. In the case of the other investigated analytes, a delay in serum separation of up to 6 hours did not significantly affect the results.

Keywords


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