A high sensitive Homocysteine (hsHCY) assay improves the clinical usefulness of this cardiovascular and cancer predictive biomarker (LB520)

Abstract

Elevated plasma Homocysteine (HCY) levels predict accelerated chronic diseases. A clinical limitation has been leakage into plasma of red cell HCY starting shortly after phlebotomy. A more stable specimen is needed especially at lower values. Specimens (N=20) were collected in EDTA tubes (current preferred specimen) and a novel cell preservative. Specimens were stored at 4±1°C until analysis. Plasma was isolated and analyzed at 0.5, 4, 8, 24, 48, 72, and 96 hours after phlebotomy using a Diazyme™ Analyzer 700 and statistically analyzed by one‐way ANOVA. HCY levels started to increase within 30 minutes in EDTA specimens while the new cell preservative sample values were stable for at least 48 hours. Indeed initial HCY levels in EDTA samples were typically 32% higher the new preservative (p<0.0001). This suggests that HCY is released to plasma from red blood cells in EDTA samples starting minutes after phlebotomy and less so in EAB cell preservative. Initial and more precise HCY can be measured and maintained for at least 48 hours when the EAB cell preservative is used as specimen anticoagulant. EDTA in contrast allows HCY increase that starts within minutes after blood draw. The reported cell preservative allows a more stable and accurate HCY assay for this predictive biomarker. More studies are needed to confirm the clinical and global predictive significance of this biomarker.