A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Homocysteine
Test Code31789
Alias/See Also
LAB93
CPT Codes
83090
Preferred Specimen
1 mL serum
Minimum Volume
0.5 mL
Other Acceptable Specimens
Plasma collected in: Sodium heparin (green-top) tube or EDTA (lavender-top) tube
Instructions
Red-top tubes: Place the specimen in a refrigerator or ice bath for 30 minutes after collection. Centrifuge the specimen as soon as possible after complete clot formation has taken place. Transfer the serum to a plastic screw-cap vial.
Barrier gel separator tubes: Place the specimen in a refrigerator for 30 minutes after collection. Centrifuge the specimen as soon as possible after complete clot formation has taken place. Do not place barrier tubes in an ice bath as freezing may prevent the barrier gel from adequately separating serum from cells.
EDTA or heparin tubes: Place the specimen in a refrigerator or ice bath until the specimen can be centrifuged. Centrifuge the specimen as soon as possible and transfer the plasma to a plastic screw-cap vial.
Barrier gel separator tubes: Place the specimen in a refrigerator for 30 minutes after collection. Centrifuge the specimen as soon as possible after complete clot formation has taken place. Do not place barrier tubes in an ice bath as freezing may prevent the barrier gel from adequately separating serum from cells.
EDTA or heparin tubes: Place the specimen in a refrigerator or ice bath until the specimen can be centrifuged. Centrifuge the specimen as soon as possible and transfer the plasma to a plastic screw-cap vial.
Transport Container
Transport tube
Transport Temperature
Room temperature
Specimen Stability
Room temperature: 4 days
Refrigerated: 14 days
Frozen: 6 months
Refrigerated: 14 days
Frozen: 6 months
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis • Grossly lipemic • Unseparated serum or plasma • Whole blood specimens
Methodology
Enzymatic
Setup Schedule
Mon-Fri
Report Available
4-7 days
Reference Range
Male | <11.4 umol/L |
Female | <10.4 umol/L |
Clinical Significance
An elevated concentration of homocysteine is an independent risk factor for cardiovascular disease. When used in conjunction with methylmalonic acid (MMA), these tests are useful to diagnose and monitor vitamin B12 (cobalamin) and folic acid deficiency and are often useful in evaluating macrocytosis (an elevated MCV, an erythrocytic index).
Performing Laboratory
Quest Diagnostics Nichols Institute-San Juan Capistrano, CA |
33608 Ortega Highway |
San Juan Capistrano, CA 92675-2042 |