Testosterone, Total
Label Mnemonic: TST
Epic Lab Code: LAB124
Downtime Form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
6240 RCP
Collection Medium:
Plasma Separator Tube 4.5 mL
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
3 mL whole blood in light green top or TWO Microtainer® devices.
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
1 hour (upon receipt in laboratory)
Reference Range:
Adult Males: 19-49 years old 249-836 ng/dL 50 years and older 193-740 ng/dL Adult Females: 19-49 years old 8-48 ng/dL 50 years and older 2-41 ng/dL Boys <1 month 75-400 ng/dL 1-5 months 14-363 ng/dL 6-24 months Less than 37 ng/dL 2-5 years Less than 19 ng/dL 6-9 years Less than 13 ng/dL 10-11 years 3-237 ng/dL 12-13 years 29-432 ng/dL 14-15 years 40-778 ng/dL 16-18 years 238-1048 ng/dL Tanner stage 1 Less than 15 ng/dL Tanner stage 2 3-432 ng/dL Tanner stage 3 65-778 ng/dL Tanner stage 4 180-763 ng/dL Tanner stage 5 188-882 ng/dL Girls Up to 30 days 20-64 ng/dL 1-5 months Less than 20 ng/dL 6-24 months Less than 9 ng/dL 2-3 years Less than 20 ng/dL 4-5 years Less than 30 ng/dL 6-7 years Less than 13 ng/dL 8-9 years 1-8 ng/dL 10-11 years 3-32 ng/dL 12-13 years 3-50 ng/dL 14-15 years 6-52 ng/dL 16-18 years 9-58 ng/dL Tanner stage I Less than 17 ng/dL Tanner stage II Less than 40 ng/dL Tanner stage III 5-63 ng/dL Tanner stage IV-V 6-58 ng/dL
This assay may be significantly impacted by high-dose biotin (>5 mg dose) taken within previous 12 hours. High concentrations of biotin may lead to falsely decreased results. These concentrations may be found in patients taking over-the-counter supplements with biotin content much higher than nutritional requirements for biotin. Specimens should not be collected until at least 12 hours after the last dose.
Test Limitations:
The assay is unaffected by icterus (bilirubin is less than 30 mg/dL), Hemolysis less than 600, lipemia less than 1000 and biotin is less than 30 ng/mL (criterion: recovery within plus or minus 10% of initial value). In vitro tests were performed on 20 commonly used pharmaceuticals. A strong interaction with Nandrolone was found. Do not use samples from patients under Nandrolone treatment. The risk of interference from potential immunological interactions between test components and rare sera has been minimized by the inclusion of suitable additives. In rare cases, interference due to extremely high titers of antibodies to ruthenium can occur. Testosterone contains additives which minimize these effects. Extremely high titers of antibodies to streptavidin can occur in isolated cases and cause interference. For diagnostic purposes, the testosterone findings should always be assessed in conjunction with the patient's medical history, clinical examination and other findings.
Electrochemiluminescence Immunoassay
CPT Code:
See Additional Information:
Biotin Interference with Immunoassays