Thyroid Antibodies Panel (TPOAb and TgAb)

Thyroid Peroxidase Antibodies (TPOAb) and Thyroglobulin Antibodies (TgAb) tests play a crucial role in the diagnosis, management, and monitoring of autoimmune thyroid diseases and help healthcare providers tailor treatment plans to individual patients' needs. Here are some reasons why the panel is done:

1. Autoimmune Thyroid Diseases (AITD) Detection: These antibodies are primarily associated with autoimmune thyroid diseases such as Hashimoto's thyroiditis (chronic lymphocytic thyroiditis) and Graves' disease. In Hashimoto's, the body's immune system mistakenly attacks the thyroid gland, leading to inflammation and eventual destruction. In Graves' disease, the antibodies stimulate the thyroid gland, leading to excessive production of thyroid hormones. Testing for TPOAb and TgAb helps in the diagnosis and monitoring of these conditions.

2. Confirmation of Hypothyroidism or Hyperthyroidism: Elevated levels of TPOAb and/or TgAb along with abnormal thyroid hormone levels can confirm the diagnosis of autoimmune thyroid disease, which can lead to either hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid).

3. Prediction of Future Thyroid Dysfunction: Detecting the presence of these antibodies in individuals with normal thyroid function can indicate an increased risk of developing thyroid dysfunction in the future. This allows for proactive management and monitoring of thyroid health.

4. Monitoring Treatment Response: For individuals diagnosed with autoimmune thyroid disease, regular monitoring of TPOAb and TgAb levels can help assess the effectiveness of treatment, such as thyroid hormone replacement therapy or anti-thyroid medications.

• TPO Antibodies (TPOAb): This test measures levels of antibodies that target an enzyme (thyroid peroxidase) crucial for thyroid hormone production. High TPOAb often indicates Hashimoto's disease, an autoimmune condition causing hypothyroidism (underactive thyroid).

• Thyroglobulin Antibodies (TgAb): This test measures antibodies against thyroglobulin, a protein the thyroid gland stores. Elevated TgAb levels can also suggest Hashimoto's disease.

Thyroid antibodies test requires a blood sample. A tourniquet (elastic) band is placed tightly on the upper arm. The patient is then asked to make a fist. This helps in the build-up of blood filling the veins. The skin is disinfected before needle insertion and the blood sample is collected in vacutainer.

Normal levels: no thyroid antibodies were found. This means that symptoms of hypothyroidism are probably not caused by an autoimmune disorder.

Abnormal results for thyroid antibodies, specifically TPO antibodies, can indicate an underlying thyroid issue, particularly autoimmune thyroid diseases. A positive TPO antibody is a common finding in Hashimoto's thyroiditis, the most frequent cause of hypothyroidism (underactive thyroid). High TPO levels suggest your immune system is attacking the thyroid gland. The severity of the elevated TPO antibodies might influence the interpretation. Very high levels are more strongly linked to Hashimoto's. Doctors often combine TPO results with other thyroid function tests (TSH, T4, Free T4) to get a complete picture.

There are no specific preparations required for the test. However, it is recommended that you consult with your healthcare provider before taking the test, as they may have specific instructions or recommendations based on your individual medical history and current health status.

The normal levels of TPO and ATG antibodies should be below 10 IU/mL. A result that is higher than 10 IU/mL indicates the presence of a thyroid disorder.

Patients should speak with their healthcare provider to determine if this test is right for them. Generally, this test is recommended in following cases:

• With known or suspected thyroid disorders such as Hashimoto’s thyroiditis
• Who have had a previous episode of hypothyroidism
• With a family history of thyroid disorders
• With unexplained fatigue, weight gain, dry skin, constipation, brittle nails, or hoarseness
• Who are being monitored for an existing thyroid disorder

Other tests that may be ordered along with a Thyroid Antibodies-TPO And ATG Serum test include:

• Thyroid-stimulating hormone (TSH)
• Free triiodothyronine (FT3)
• Free thyroxine (FT4)
• Ultrasound of the thyroid
• Radioactive iodine uptake (RAIU)

• Thyroid Peroxidase Antibodies (TPOAb)
• Anti-Thyroglobulin Antibodies (ATG/ TGAb)