| Test Name: | Homocysteine |
| Epic Order Code: | LAB93 |
| CPT Code: | 83090 | | |
| Specimen(s) Type: | Serum; 1.0 mL |
| Acceptable Container(s): |   Tops are gold and red. |
| Testing Schedule: | Monday-Friday |
| Turn Around Time: | STAT: NA |
| | Routine: 1-3 days |
| Collection Information: | No special patient preparation is required. Obtain specimen by standard collection procedures. |
| Transport Information: | Deliver to lab immediately on ice. All specimens must be signed into the laboratory. |
| Reference Clients: | If unable to deliver to the lab immediately on ice, centrifuge the specimen and remove serum from the red cells. Store and transport at 2-8° C. Specimen must be received in the lab within 14 days. If longer storage is required, store and transport the sample at -20° C for up to 1 year. |
| Causes for Rejection: | Improperly labeled, incorrect container, contaminated, insufficient quantity, incorrect/delay in transport, gross hemolysis. |
| Reference Range: | Male: 5.46 - 16.20 µmol/L |
| | Female: 4.44 - 13.56 µmol/L |
| Additional Information: | The following drugs may elevate levels of homocysteine: methotrexate, carbamazepine, phenytoin, nitrous oxide, anticonvulsants and 6-azauridine triacetate. The mechanism of action of these drugs affects different parts of the metabolic pathway of homocysteine. |