Contributed by – Healthians Team
What is the TPO test?
A thyroid peroxidase antibodies test is the most sensitive test for detecting autoimmune disorder. The test depicts the levels of antibodies made against the compound thyroid peroxidase (TPO) in the blood. Thyroid peroxidase (TPO) is an enzyme found in the thyroid gland. This enzyme plays a key role in the production of thyroid hormones and is a necessary component of the thyroid tissue.
The presence of raised TPO antibodies in your blood is an indicator that the cause of thyroid disease is an autoimmune disorder, such as Hashimoto’s thyroiditis or Graves’ disease. These antibodies identify the thyroid as a foreign agent and signal the immune system to attack the glands. This damages your thyroid gland and causes swelling and reduced function of the thyroid.
Who should get a TPO test?
Your doctor might order a TPO antibody test to diagnose certain suggestive symptoms and physical findings that indicate that your body could be affected by autoimmune disorder that involves the thyroid. It may also be performed as a follow-up when other thyroid test results (such as T3, T4, and/or TSH) show signs of thyroid dysfunction.
- Rapid heart rate
- Anxiety
- Tremors
- Hair loss
- Dry skin
- Intolerance to cold
- Constipation
- Sweating & Palpitations
- Difficulty in sleeping
- Protruding eyes
- Sudden weight loss or gain
- Fatigue and sluggishness
Why is the TPO test needed?
Whether for thyroid disease or thyroid surgery, the TPO test is indispensable. The test is a primary marker to identify autoimmune and thyroid disorders like hypothyroidism, hyperthyroidism, goitre, Hashimoto thyroiditis, graves disease, and other thyroid abnormalities.
The other names of this test are Thyroid autoantibody, antimicrosomal antibody, antithyroid antibody, TPOAb, TgAb, Anti-TPO, and TBII.
What does a TPO test result mean?
In general, you may want your TPO antibodies to be as low as possible.
The reason is simple:
The presence of antibodies indicates potential damage to your thyroid gland. Therefore having those antibodies as low as possible will definitely increase your chances that very little to no damage is taking place.
The diagnostic criterion for ideal range of TPO-Ab (+) was defined as below 16 IU/mL.
A negative result for the anti microsomal antibody /antithyroid microsomal antibodies is a normal result. Should the anti-TPO test results show slightly raised or outside of the reference range, here are the possible conditions:
- Grave’s disease
- Hashimoto Thyroiditis
- Subacute thyroiditis
- Autoimmune haemolytic anaemia
- Thyroid cancer
- Rheumatoid arthritis
TPO levels cannot and should not be evaluated in isolation, but should be used along with other tests to provide valuable data as markers of hypothyroidism.
How is the TPO test done?
This test requires a sample of blood to be drawn from a vein, usually from the forearm. There is usually no special preparation required prior to the test. Fasting is not necessary. The blood sample is sent to a lab for clinical analysis. You can return to your usual activities immediately. It is advised to inform your doctor of any medication, drugs or supplements you may be taking before you go in for the test.
Remember, it might be worthwhile for you to catch your diagnosis early so you can prevent the disease state from worsening.
