This test may exhibit interference when sample is collected from a person who is consuming a supplement with a high dose of biotin (also termed as vitamin B7 or B8, vitamin H, or coenzyme R). It is recommended to ask all patients who may be indicated for this test about biotin supplementation. Patients should be cautioned to stop biotin consumption at least 72 hours prior to the collection of a sample.
1 - 3 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Serum
1 mL
0.7 mL (Note: This volume does not allow for repeat testing.)
Gel-barrier tube (preferred) or red-top tube
If a red-top tube is used, transfer separated serum to a plastic transport tube.
Refrigerate.
Temperature
Period
Room temperature
Unstable (stability provided by manufacturer or literature reference)
Refrigerated
6 days (stability provided by manufacturer or literature reference)
Frozen
12 months (stability provided by manufacturer or literature reference)
Freeze/thaw cycles
Stable x1 (stability provided by manufacturer or literature reference)
Citrate plasma specimen; samples collected in heparin or samples from patients on heparin therapy; lipemic or hemolyzed serum samples; improper labeling
Diagnosis of hyperthyroidism and Graves' disease
Electrochemiluminescence immunoassay (ECLIA)
0.0-1.75 units/L
Thyrotropin-receptor antibody is an autoantibody to the thyroid cell receptor for thyroid-stimulating hormone. It can be demonstrated in 90% of patients with Graves' disease, and is the cause of the hyperthyroidism of that condition. The characterization of TRA resolved much confusion about long-acting thyroid stimulator (LATS) and LATS protector, which are both, in fact, thyroid-stimulating autoantibodies which simply behaved differently in animal test systems. These antibodies are present in 50% of euthyroid Graves' disease as well as hyperthyroid patients. They play a major role in the pathogenesis of Graves' disease. Detection of these antibodies is useful in prediction of neonatal hyperthyroidism and prediction of relapse of hyperthyroidism.
