Acceptable screening test for disorders of methionine metabolism (congenital hyperhomocysteinemia). Not recommended for risk assessment of cardiovascular disease or venous thromboembolism.
Quantitative Enzymatic Assay
Within 24 hours
New York DOH Approval Status
Green (lithium heparin), serum separator tube, or EDTA (K2 and K3).
Serum or plasma must be separated immediately after collection. If immediate centrifugation is not possible, collected blood specimens should be kept on ice and centrifuged within one hour. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)
Ambient: 4 days; Refrigerated: 1 month; Frozen: 10 months
Effective January 4, 2021:
0-15 µmol/L, for both male and female
Elevated total homocysteine (tHcy) concentrations may be associated with vitamin B12 deficiency, folate deficiency, or inherited disorders of methionine metabolism. tHcy may also be used as a weak-graded risk factor for cardiovascular disease or stroke.
False elevations of plasma or serum homocysteine may occur if the plasma or serum is not promptly separated from the cells at the time of collection. Fasting specimen preferred.
|Component Test Code*||Component Chart Name||LOINC|
- Plasma Total Homocysteine