Test ID BLOD0214 Thyroid-Stimulating Immunoglobulin, Serum
Useful For
Second-order testing for autoimmune thyroid disease, including:
-Differential diagnosis of etiology of thyrotoxicosis in patients with ambiguous clinical signs or contraindicated (eg, pregnant or breast-feeding) or indeterminate thyroid radioisotope scans
-Diagnosis of clinically suspected Graves disease (eg, extrathyroidal manifestations of Graves disease: endocrine exophthalmos, pretibial myxedema, thyroid acropachy) but normal thyroid function tests
-Determining the risk of neonatal thyrotoxicosis in a fetus of a pregnant female with active or past Graves disease
-Differential diagnosis of gestational thyrotoxicosis versus first-trimester manifestation or recurrence of Graves disease
-Assessing the risk of Graves disease relapse after antithyroid drug treatment
A combination of TSI / Thyroid-Stimulating Immunoglobulin, Serum and THYRO / Thyrotropin Receptor Antibody, Serum is useful as an adjunct in the diagnosis of unusual cases of hypothyroidism (eg, Hashitoxicosis).
Specimen Type
SerumOrdering Guidance
This test is used for second-order testing for autoimmune thyroid disease.
For suspected cases of autoimmune hypothyroidism, the first-order testing is TPO / Thyroperoxidase Antibodies, Serum.
For suspected cases of autoimmune thyroid disease, first-order testing includes TPO and THYRO / Thyrotropin Receptor Antibody, Serum.
Specimen Required
Collection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Specimen Minimum Volume
0.3 mL
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | OK |
Gross icterus | OK |
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Frozen (preferred) | 60 days | |
Refrigerated | 7 days | ||
Ambient | 24 hours |
Day(s) Performed
Monday through Friday
Report Available
2 to 6 daysMethod Name
Recombinant Bioassay
Performing Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
84445
Reporting Name
Thyroid-Stimulating Immunoglob, SReference Values
≤1.3 TSI index
Reference values apply to all ages.
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.Forms
If not ordering electronically, complete, print, and send a General Request (T239) with the specimen.
Secondary ID
8634SANFORD INTERFACE BUILD INFORMATION
Result Code | Result Code Description |
---|---|
3914 | Thyroid Stimulating Immunoglobul |