Poona Diagnostic Centre

Thyroid Function Tests (TFT) are a series of blood tests used to evaluate the health and functioning of the thyroid gland, a critical organ that regulates metabolism, energy production, and overall hormonal balance in the body. These tests are essential for diagnosing and managing thyroid disorders such as hypothyroidism, hyperthyroidism, and other conditions affecting the thyroid gland.

1. Thyroxine (T4):

   • Measures the primary hormone produced by the thyroid gland.
   • Abnormal levels can indicate either an underactive thyroid (hypothyroidism) or an overactive thyroid (hyperthyroidism).
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2. Triiodothyronine (T3):

   • Evaluates the active form of thyroid hormone.
   • Elevated T3 levels often point to hyperthyroidism, while low levels may suggest hypothyroidism or a severe chronic illness.
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3. Thyroid-Stimulating Hormone (TSH):

   • Produced by the pituitary gland, TSH regulates thyroid hormone production.
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   • High TSH levels usually indicate hypothyroidism, while low levels suggest hyperthyroidism.
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4. Free T4 and Free T3:

   • Measure the unbound (active) forms of T4 and T3 hormones.
   • These provide a more accurate picture of the thyroid’s activity, unaffected by protein levels in the blood.
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5. Additional Tests (if needed):

   • Anti-thyroid antibodies: To detect autoimmune conditions like Hashimoto’s thyroiditis or Graves’ disease.
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   • Thyroglobulin or Calcitonin: Used in specific conditions like thyroid cancer monitoring.

TFTs are crucial for diagnosing:

• Hypothyroidism: Symptoms include fatigue, weight gain, cold intolerance, and depression.
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• Hyperthyroidism: Symptoms include weight loss, anxiety, tremors, and heat intolerance.
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• Autoimmune thyroid disorders: Such as Graves' disease and Hashimoto’s thyroiditis.
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• Thyroid nodules or goiters: These tests help in understanding whether these are hormone-producing.

TFTs are prescribed for individuals experiencing symptoms of thyroid dysfunction, as part of routine health check-ups, or for monitoring the effectiveness of thyroid medications. In pregnant women, TFTs are critical to ensure optimal thyroid function, which is vital for fetal development.

Regular thyroid screening and accurate interpretation of TFT results enable early intervention, effective treatment, and improved management of thyroid-related health conditions.