Comparative Study of Ethylenediaminetetraacetic Acid Plasma versus Serum for Assay of Biochemical Parameters

Abstract

Objective: The objective of the study was to assess the usefulness of ethylenediaminetetraacetic acid (EDTA) plasma as an alternative to serum for glucose, renal function test, and liver function test. Need for the Study:The use of plasma as compared to serum decreases the turnaround time, coagulation- induced interferences, gives high sample volume for analysis, and is economical. Methodology An observational cross-sectional study was done on blood samples of 51 patients. A 4 ml of blood was drawn from each patient by standard venipuncture technique. A 2 ml was collected in a plain red top Vacutainer and 2 ml in an EDTA Vacutainer. Red top tubes, after 20 min of clotting, were centrifuged for 5 min at 5000 rpm to separate serum. EDTA tubes were centrifuged immediately at 5000 rpm to separate plasma. Serum and plasma were analyzed with ERBA-EM-360 autoanalyzer for glucose, urea, creatinine, total bilirubin, direct bilirubin, total protein, albumin, aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP). Results obtained were analyzed using paired “t-test.” Results: Values of glucose, urea, total bilirubin, direct bilirubin, total protein, albumin, and ALP in serum and plasma samples showed statistically significant difference with P 0.05. Conclusion:EDTA plasma can be used as an alternative to serum for creatinine, AST, and ALT but its use for urea, total bilirubin, direct bilirubin, total protein, albumin, and for ALP may not be appropriate.

Keywords

• biochemical assay
• ethylenediaminetetraacetic acid
• liver function tests
• plasma
• renal function