Thyroid Stimulating Hormone (TSH), Reflexive
Order Code: TSHR
Order Form: Laboratory Requisition
Specimen:
Plasma
Collection Medium:
Plasma Separator Tube
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
3 mL whole blood in light green top or THREE microtainers.
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Analytic Time:
1 hour (upon receipt in laboratory)
Reference Range:
AGE MALES AND FEMALES 1 - 11 months 0.8-6.3 mIU/mL 1 - 5 years 0.7-5.9 mIU/mL > 5 years Same as adult values Adults 0.27-4.20 mIU/mL
Comments:
If TSH is outside the adult reference range, a Free T4 is automatically analyzed, at an additional charge to the patient. Please print, complete and submit the Advance Beneficiary Notice (ABN) along with the Laboratory Requisition before shipping the specimen. New analytical immunoassay with different reference range instituted 4/24/00 at 1000.
Test Limitations:
The assay is unaffected by icterus (bilirubin is less than 41 mg/dL), hemolysis (Hb is less than 1000 mg/dL), lipemia (Intralipid is less than 1500 mg/dL) and biotin is less than 25 ng/mL (criterion: recovery within plus or minus 10% of initial value). In patients receiving therapy with high biotin doses (i.e. is greater than 5 mg/day) no sample should be taken until at least 8 hours after the last biotin administration. No interference was observed from rheumatoid factor (up to 3250 U/mL) and samples from dialysis patients. There is no high-dose hook effect for TSH concentrations up to 1000 μIU/mL. In vitro tests were performed on 26 commonly used pharmaceuticals. No interference with the assay was found. As with all tests containing monoclonal mouse antibodies, erroneous findings may be obtained from samples taken from patients who have been treated with monoclonal mouse antibodies or have received them for diagnostic purposes. In rare cases, interference due to extremely high titers of antibodies to ruthenium can occur. TSH reagent 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 TSH findings should always be assessed in conjunction with the patient's medical history, clinical examination and other findings.
Methodology:
Electrochemiluminescence Immunoassay
Sample Processing:
Centrifuge at 3000 RPM for 10 minutes.
Aliquot plasma into labeled container and cap.
Sample Storage:
Room temperature or refrigerate if stored overnight, weekends or holidays.
Transport Instructions:
Place specimen into zip-lock type bag, seal bag.
Place requisition into outside pocket of bag.
Ship ambient or refrigerate.
CPT Code:
84443