Can this result diagnose a condition on its own?

No. Hormone tests are interpreted together with symptoms, medical history, and other laboratory results.

Which reference range should I use?

Use the reference interval provided by the laboratory that performed your test.

When should I discuss the result with a healthcare professional?

Results that are clearly outside range, persistent, or inconsistent with symptoms should be reviewed by a healthcare professional.

Information about a laboratory test

Anti-Tg (TgAb): What Does This Blood Test Measure?

Measures antibodies directed against the thyroid protein thyroglobulin.

Test summary

Test name: Anti-Tg (TgAb)
Abbreviations: TgAb, Anti-Tg
Category: Endocrinology / Thyroid Autoimmunity
Panel: Thyroid Antibody Tests
Specimen: Serum / plasma
Common units: IU/mL, kIU/L

What does the test measure?

Measures antibodies directed against the thyroid protein thyroglobulin.

Why is the test ordered?

Used in evaluating autoimmune thyroid disease and in interpreting thyroglobulin testing.

Information about a low result

Negative Anti-Tg does not completely exclude autoimmune thyroid disease.

Information about a high result

High Anti-Tg may occur in autoimmune thyroid disease and can interfere with thyroglobulin measurement.

Reference and clinical context

Use the reference interval printed on your own laboratory report first. Hormone results may vary with the assay, age, sex, pregnancy, menstrual-cycle phase, and sampling time.

Reference ranges may vary by laboratory, method used, age, sex, pregnancy status, and clinical context. The reference range on your own laboratory report takes precedence.

Interpretation notes

When thyroglobulin is used after thyroid-cancer treatment, Anti-Tg status is particularly important; assay method and using the same laboratory also matter.

Related specialties

Endocrinology
Internal Medicine
Nuclear Medicine
Medical Oncology

Frequently asked questions

More information about this test

High Anti-Tg (TgAb): What Does It Mean?

Sources

Hashimoto's Disease — National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
U.S. government medical reference · 2026 · Hashimoto disease; TSH/T4/T3 and TPO antibody context · Verified: Aug 11, 2026
Thyroid Antibodies — U.S. National Library of Medicine (MedlinePlus)
Government medical reference · 2023 · TPOAb, TgAb and TRAb; autoimmune-thyroid context · Verified: Aug 11, 2026
Thyroglobulin — U.S. National Library of Medicine (MedlinePlus)
Government medical reference · 2026 · Thyroglobulin follow-up after thyroid-cancer treatment; method and anti-Tg interference · Verified: Aug 11, 2026