The thyroid is a butterfly-shaped gland located in the neck and produces thyroid hormones. Thyroid disorders, which are when the gland produces too much or too little hormone, can affect a variety of body functions, from heart rate to metabolism. Your doctor may run tests if you think your thyroid is overactive or underactive. Reading these test results may seem difficult; but if you adopt a systematic approach and understand what each test represents, you can determine whether or not your body does have a thyroid disorder, and the type of disorder. Remember that only a doctor can diagnose an illness so make sure you discuss the test results with him or her so that treatment can be started, if needed.
Part 1 of 3: Understanding TSH Hasil Results
Step 1. Check if the TSH result is within the normal range
The first thyroid test that doctors usually do is a TSH test which stands for "Thyroid Stimulating Hormone" (thyroid stimulating hormone) which is produced by the pituitary gland and stimulates the thyroid to release the hormones T4 and T3.
- TSH can be considered the “engine” of the thyroid gland because it determines the amount of thyroid hormone produced and then released from the thyroid throughout the body.
- Normal TSH values are between 0.4 – 4.0 mIU/L.
- You can breathe a sigh of relief if your TSH test results fall within this range; however, it does not mean that the owner of a normal TSH value is not free from thyroid disorders. A TSH value that is at a high threshold can indicate the development of a thyroid disorder.
- Most thyroid disorders require 1-2 tests to be detected and diagnosed due to the complex relationship of the various hormones that contribute to thyroid function.
- If you think you have a thyroid disorder, your doctor may run additional tests even if your TSH result is normal.
Step 2. Understand the possible meaning of a high TSH test result
TSH tells the thyroid to produce more T4 and T3, which release hormones from the thyroid (on the orders of TSH) to act throughout the body. If the thyroid is underactive, it means the gland is not releasing enough T3 and T4 so the pituitary gland will release more TSH to try and compensate.
- Thus, a high TSH can be a sign that you have a hypothyroid disorder (a condition in which there is not enough hormone production by the thyroid gland).
- However, you will need further tests to investigate further and confirm the correct diagnosis.
Step 3. Look for signs and symptoms of hypothyroidism
In addition to high TSH test results, various clinical indications can also show symptoms of hypothyroidism. Tell your doctor if you experience any of the following symptoms:
- Increased sensitivity to cold
- Gaining weight for no reason
- Unusually dry skin
- Muscle pain and stiffness
- Joint pain and swelling
- Depression and/or other mood swings
- Slower heart rate
- Thinning hair
- Changes in the menstrual cycle
- Slowing down of speech or thinking
Step 4. Evaluate the meaning behind a very low TSH result
On the other hand, if your TSH test results are very low, this may be the body's response to the pituitary gland to produce less TSH as a result too much thyroid hormones in the body (T3 and T4). Therefore, a low TSH test result can indicate hyperthyroidism (overproduction of thyroid hormone).
- Again, further blood tests are needed to confirm the diagnosis.
- The results of a TSH test alone can guide a doctor down a particular path, but are usually not diagnostic.
Step 5. Watch for signs and symptoms of hyperthyroidism
In addition to a low TSH test result, hyperthyroidism can show various clinical indications. Tell your doctor if you experience any of the following symptoms of hyperthyroidism:
- Heart rate that is faster than normal
- Weight loss for no reason
- Increased appetite
- Tremors, often in the hands
- Restlessness, irritability, and/or other mood swings
- More frequent bowel movements
- Enlargement of the thyroid gland (can be felt in the neck, and is called a "goiter")
- Eyes protruding or sticking out more than usual (this symptom occurs in a type of hyperthyroidism called Grave's disease; furthermore, this eye condition is called "Grave's ophthalmopathy")
Step 6. Use the TSH test results to monitor ongoing thyroid care
If you have been diagnosed with a thyroid disorder and are on ongoing treatment, your doctor will recommend that you get regular TSH tests to check and make sure the treatment is effective. Continuous monitoring can also ensure that TSH levels remain within target ranges.
- Treatment for hypothyroidism and hyperthyroidism is very different.
- The target range for thyroid treatment is usually a TSH of 0.4 – 4.0 mIU/L, although this may vary depending on the type of thyroid disorder you have.
- Monitoring will be more frequent at the start of treatment, until a routine that maintains TSH consistency is established (at this point monitoring does not need to be too frequent, usually every 12 months).
Part 2 of 3: Interpreting Free T4 and T3 Test Results
Step 1. Check if your T4 test result is within normal range
T4 is the hormone that is most commonly measured because it is directly produced by the thyroid gland, and is continuously released to circulate throughout the body. The normal free T4 range is between 0.8 – 2.8 ng/dL.
- The exact number depends on the laboratory and the specific type of test performed.
- Typically, most laboratory results list the normal range next to the measurement result to make it easier for patients to tell if their T4 level is too low, normal, or high.
Step 2. Understand the T4 value in relation to the TSH value
If the TSH value tall abnormally (indicative of possible hypothyroidism), elevated T4 levels low will confirm the diagnosis of hypothyroidism.
As previously mentioned, these results should be interpreted in relation to TSH values and under the guidance of medical professionals
Step 3. Review T3 test scores for possible hyperthyroidism
T3 is another hormone produced by the thyroid gland, but usually in much less quantity than T4. T4 hormone is the primary thyroid hormone in the diagnosis of thyroid conditions. However, there are certain cases of hyperthyroidism, in which the T3 hormone rises significantly and T4 remains normal (under certain disease states); this is where the measurement of T3 becomes very important.
- If the T4 value is normal but the TSH is low, a high T3 value can confirm the diagnosis of hyperthyroidism.
- Although the T3 value can provide important information in the diagnosis of hyperthyroidism, it is not helpful in the diagnosis of hypothyroidism.
- The normal free T3 range usually ranges from 2.3–4.2 pg/mL in adults over 18 years of age.
- Again, the exact number may vary depending on the laboratory and the specific type of test performed. Most lab results list a normal range next to the measurement result so you can easily determine whether a T3 value is too low, normal, or high.
Part 3 of 3: Reading Other Thyroid Test Results
Step 1. Involve the doctor
One of the beauties of our medical system is that patients don't have to interpret their own test results. The doctor will run the test and interpret the results for you. He can provide a diagnosis and initiate a treatment plan, which involves a combination of medication and lifestyle changes. Having a general knowledge of test results and what they mean can help you understand the disorder and the treatment you are undergoing.
Conducting the test yourself can be dangerous and lead to mistreatment. You won't be repairing a car engine if you haven't received any prior training; it is also the same
Step 2. Interpret thyroid antibody testing to differentiate between different types of thyroid disease
If you are diagnosed with a thyroid disorder, your doctor will order other thyroid investigations to confirm the diagnosis. An antibody test is usually done to get important clues about what's going on in your thyroid.
- Thyroid antibody tests can help differentiate between different types of thyroiditis as well as autoimmune thyroid conditions.
- TPO (thyroid peroxidase antibody aka thyroid peroxidase antibody) can be elevated in autoimmune thyroid conditions such as Grave's Disease or Hashimoto's Thyroiditis.
- TG (thyroglobulin antibody aka thyroglobulin antibody) may also be elevated in Grave's Disease or Hashimoto's Thyroiditis.
- TSHR (TSH receptor antibodies aka TSH receptor antibodies) can be elevated in Grave's Disease.
Step 3. Measure your calcitonin
A calcitonin test may be performed to further investigate thyroid disorders. Calcitonin may be elevated in the case of thyroid cancer (which can be the underlying cause of various thyroid dysfunctions). Calcitonin values can also be high in cases of C-cell hyperplasia, which is another form of abnormal cell growth in the thyroid gland.
Step 4. Get an ultrasound, biopsy, or iodine test to confirm a specific thyroid diagnosis
Although doctors can obtain a lot of important information through blood tests to detect and diagnose thyroid disorders, in some cases a more in-depth investigation is needed to determine the actual condition. Your doctor will tell you if further tests need to be done, such as a thyroid ultrasound, biopsy, or iodine test.
- A thyroid ultrasound can be used to identify thyroid nodules. If a nodule is found, an ultrasound can determine whether the nodule is solid or cystic (fluid-filled), and both require different treatment methods. Ultrasound can be used to monitor the growth or change in the nodule over time.
- A thyroid biopsy can sample suspicious nodules and rule out cancer.
- An iodine uptake scan can measure the area of the thyroid that is active (eg functional). These scans can also identify areas that are inactive (non-functional) or hyperactive (over-functioning).