Hemostasis - Homocysteine

Test Description
Test Name	Homocysteine
Synonym(s)
Description	Homocysteine(HCY) is a naturally occurring amino acid that is formed from methionine as a product of numerous S-adenosyl methionine-dependent transmethylation reactions. The metabolism of HCY is regulated by three enzymatic pathways that either convert HCY into cysteine or remethylate it back into methionine. If one or more of the HCY metabolic pathways are inhibited due to enzymatic defects or vitamin deficiencies, HCY accumulates, causing an increased HCY level in plasma. Recently, several clinical and epidemiological studies have indicated that even a moderately elevated plasma HCY level is a predictor for cardiovascular disease.
Methodology	Immunoassay
Performed	Monday - Friday
Turnaround Time	1-3 days
Specimen Requirements	5 mL EDTA plasma (lavender top tube) Fasting specimen is preferred. Plasma must be separated from cells within 1 hour of collection. Homocysteine levels increase when separation from the cells is delayed. If sample cannot be separated from cell, store sample on ice until centrifugation. Freeze immediately and transport frozen
Rejection Criteria	Specimen clotted, hemolyzed, contaminated with heparin; frozen specimen received thawed
CPT Code(s)	83090
Reference Range	5 – 9 umol/L
Contact Information	Hemostasis Lab: 214-645-5067 Customer Service: 214-645-7057, Toll Free 877-887-8136