| 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 # |
Testosterone, Total, Males (Adult), Immunoassay
Test Code19958
CPT Codes
84403
Preferred Specimen
1 mL serum
Patient Preparation
Due to changes in testosterone levels throughout the day, two morning (8:00-10:00 a.m.) specimens obtained on different days are recommended by The Endocrine Society for screening.
Minimum Volume
0.5 mL
Instructions
Dietary supplements containing biotin may interfere in assays and may skew results to be either falsely high or falsely low. For patients receiving the recommended daily doses of biotin, draw samples at least 8 hours following the last biotin supplementation. For patients on mega-doses of biotin supplements, draw samples at least 72 hours following the last biotin supplementation.
Samples with Fluorescein may cause falsely depressed results. Evidence suggests that patients undergoing retinal fluorescein angiography can retain amounts of Fluorescein in the body for up to 72 hours post-treatment.
Note: This assay should be performed on adult (≥ 18 years) males.
Samples with Fluorescein may cause falsely depressed results. Evidence suggests that patients undergoing retinal fluorescein angiography can retain amounts of Fluorescein in the body for up to 72 hours post-treatment.
Note: This assay should be performed on adult (≥ 18 years) males.
Transport Temperature
Room temperature
Specimen Stability
Room temperature: 5 days
Refrigerated: 7 days
Frozen: 21 days
Refrigerated: 7 days
Frozen: 21 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Grossly icteric
Methodology
Immunoassay (IA)
Setup Schedule
Set up: Mon-Sat; Report available: Next day
Limitations
Immunoassay does not provide sufficient sensitivity in detecting low concentrations among non-adults and women.
Clinical Significance
Testosterone circulates almost entirely bound to transport proteins: Normally less than 1-2% is free. The principal transport protein for testosterone is known as sex hormone binding globulin (SHBG) or testosterone-estradiol binding globulin (TeBG). Testosterone measurements are used to assess erectile dysfunction, infertility, gynecomastia, and osteoporosis and to assess hormone replacement therapy.
