Laboratory Test Information Guide

Details for Homocysteine

Test Name: Homocysteine
Alternate Name(s): Total Homocysteine
Laboratory: Core (UH)
Specimen Type: 4 mL K2 or K3 EDTA Lavender top Vacutainer tube

Note: Specimens not placed on ice immediately may exhibit a 10-20% increase in concentration.
Collection Information: A blood sample collected in an EDTA Lavender top Vacutainer tube is required.

Minimum sample volume of 300 uL of plasma is required

Place tube on ice after collection and deliver to lab immediately to centrifuge and separate plasma from RBCs.

Freeze plasma.

Note: Specimens not placed on ice immediately may exhibit a 10-20% increase in concentration
Test Schedule: Thursdays
Turnaround time from when specimen
is received in testing laboratory:
5-7 days
Reference Range: 
AgeReference Interval
<13 10 umol/L
1-<12 years3 8 umol/L
12-<15 years: Female4 10 umol/L
12-<15 years: Male5 10 umol/L
>=18 years<=14 umol/L
Effective Date:  
Revised Date: 2021-09-02
Critical Value:  
Interpretive Comments:  
Special Processing: Do not store samples at room temperature.
Keep Vacutainer on ice until centrifugation then freeze.
Freeze plasma at -30 degrees Celsius.
Comments: Drugs that interfere with homocysteine metabolism, e.g. nitric oxide, methotrexate, isoniazid, penicillamine and various antiepileptic drugs: carbamazepine, phenytoin, may give elevated levels of total homocysteine.
Method of Analysis: Enzymatic
Critical Information Required:  
Storage & Shipment:  
System Codes: 
Referred To:  

Questions? Comments? Contact Laura Gopaul