The thyroid is a butterfly-shaped gland found in the neck that produces thyroid hormone. Disorders that affect it can trigger excessive or insufficient hormone secretion, which in turn affects many body functions, from heart rate to metabolism. If your doctor thinks you have an overactive or underactive thyroid, they may order tests. Reading the report might seem complex; however, if you use a systematic approach and understand the meaning of each test, you can understand whether or not you have thyroid problems and, if so, identify what ails you. However, remember that only the doctor can make a precise diagnosis, so you must discuss the results with him in order to be able to undergo treatment.
Steps
Part 1 of 3: Understanding TSH Values
Step 1. Check the TSH data to see if it is within the normal range
The first test that is usually done is that of TSH, the thyroid stimulating hormone or thyrotropin, which is produced by the pituitary gland to stimulate the thyroid to secrete the hormones T4 and T3.
- You can think of TSH as the gland's "engine" that determines the doses of hormones it synthesizes and releases into the body.
- A normal value is between 0.4 and 4.0 mUI / l.
- If your tests show that your TSH is within this range, that's a good sign; however, this does not completely rule out the presence of thyroid disorders; if the value tends to be high, it could indicate a developing problem.
- Two or more tests are required to diagnose most disorders of this gland, due to the complex interaction between the various hormones that contribute to thyroid function.
- If your doctor suspects something abnormal, he may prescribe other tests, even if the TSH concentration is normal.
Step 2. Interpret the possible meanings of a high TSH
This substance causes the gland to secrete greater amounts of T4 and T3, the thyroid hormones, which are then released into the body. If the gland is underactive, it does not produce it in sufficient doses, consequently the pituitary "tries to stimulate it" and compensate for this situation by increasing the TSH.
- For this reason, a high TSH value could be an indication of hypothyroidism (the thyroid does not produce sufficient quantities of hormones).
- In this case, you need to undergo other tests to get more detailed information and make a diagnosis.
Step 3. Look for symptoms and signs of hypothyroidism
In addition to an excessive concentration of TSH, this disorder has some clinical manifestations; Tell your doctor if you complain of any of the symptoms described below, as they may suggest you have an underactive thyroid:
- Increased sensitivity to cold.
- Exhaustion.
- Unexplained weight gain.
- Dry skin.
- Constipation.
- Muscle aches and stiffness.
- Joint pain and swelling.
- Depression and / or mood swings.
- Abnormal bradycardia.
- Sparse hair.
- Changes in the menstrual cycle.
- Slowing of cognitive functions or speech.
Step 4. Evaluate the possible significance of a reduced TSH
If from the analyzes you find an insufficient concentration of TSH, know that it could be the reaction of the pituitary, which secretes doses minors of hormone to balance a excess of T3 and T4. For this reason, a TSH value below the minimum limit could be an indication of hyperthyroidism (excessive production of thyroid hormones).
- Again, further blood tests are needed to confirm the diagnosis.
- The TSH value can direct the doctor towards a diagnostic path, but alone it is not sufficient to reach certain conclusions.
Step 5. Watch for signs and symptoms of hyperthyroidism
This disorder manifests itself with various clinical signs, as well as reduced concentrations of TSH. Tell your doctor if you have any discomfort described below, as it could be a sign of an overactive thyroid:
- Heart rate higher than usual.
- Unexplained weight loss.
- Increased appetite.
- Sweats.
- Tremors, especially of the hands.
- Anxiety, irritability and / or mood swings.
- Exhaustion.
- Frequent evacuation.
- Dilated thyroid gland (you can feel it in the neck, this pathological condition is called struma or goiter).
- Sleep disorders.
- Eyes bulging or protruding more than normal (this sign is present in a form of hyperthyroidism called Basedow-Graves disease and is referred to as "Graves' ophthalmopathy").
Step 6. Use the TSH value to monitor the effects of therapies
If you have been diagnosed with a thyroid disorder and are undergoing treatment, your doctor is likely to have regular tests to measure your TSH concentration, in order to check the situation and confirm that the treatment is effective; continuous monitoring ensures that values remain within the normal range.
- The therapies for hypothyroidism and hyperthyroidism are very different from each other.
- The goal of treatment is to bring TSH values into the range of 0.4 to 4.0 mUI / L, although there may be variations based on the type of disease you suffer from.
- You probably have to undergo more frequent checks at the beginning of treatment, until a routine is established and TSH values stabilize (at this point the tests are less close and one check per year is sufficient).
Part 2 of 3: Interpreting the Free T4 and T3 Values
Step 1. Check that the concentration of T4 (free thyroxine) is normal
It is the hormone that is tested most frequently, it is produced directly by the thyroid and released into the bloodstream. Normal values are between 0.8 and 2.8 ng / dl.
- Exact values may vary depending on the laboratory performing the analyzes and the type of test performed.
- However, most laboratories produce a report in which the normal reference ranges are present, so you can easily understand if the T4 concentration is high, low or average.
Step 2. Interpret the values of T4 in relation to those of TSH
If the concentration of the thyroid stimulating hormone is too high high (possible hypothyroidism), a reduction thyroxine supports the diagnosis of underactive thyroid. Instead, if the TSH is high (possible hyperthyroidism), a value of T4 superior at the limit of normal strengthens the suspicions that the thyroid is too active.
As previously stated, it is best to study the outcomes also taking into account those of the thyroid stimulating hormone and under the guidance of a physician
Step 3. In case of possible hyperthyroidism, evaluate the data related to T3 (triiodothyronine)
It is another hormone secreted by the gland, but in less significant quantities than those of T4. Thyroxine is the main substance that is monitored to diagnose thyroid pathologies; however, there are some cases of hyperthyroidism in which the concentrations of T4 remain normal and those of T3 are very high, so it is essential to measure them.
- If thyroxine levels are within the normal range but TSH levels are low, an excessive T3 concentration confirms the diagnosis of hyperthyroidism.
- Although triiodothyronine is useful in recognizing hyperthyroidism, it has no diagnostic value with regards to hypothyroidism.
- In adults over 18 years of age, free T3 is normally present in concentrations between 2, 3 and 4, 2 pg / ml.
- Also in this case, the values may vary according to the laboratory and the test performed; however, most testing centers draw up a report indicating the normal range and which allows you to understand if the results are low, high or average.
Part 3 of 3: Read Other Data
Step 1. Involve your doctor
The patient does not have to interpret the results of his tests alone, for this purpose he can entrust the doctor who prescribed the tests, who is able to formulate a diagnosis and plan a therapy that includes a series of lifestyle changes and taking medications. Having a general understanding of values and their meaning allows you to better understand the ailment that ails you and the treatment needed.
You cannot "self-prescribe" exams, interpreting the results yourself is dangerous and could lead you to plan a wrong therapy. Just as you wouldn't try to fix an engine if you're not a mechanic, don't try to heal yourself if you're not a doctor
Step 2. Read the thyroid antibody values to distinguish the various pathologies of the gland
If you have been diagnosed with this type of disorder, your doctor will probably prescribe a series of further tests to get a complete picture of the situation and confirm your hypothesis; Typically, antibody testing is done which provides important clues.
- The examination allows to distinguish the various thyroid pathologies, including those of an autoimmune nature.
- The TPO (thyroid peroxidase) enzyme can have elevated levels in the presence of autoimmune diseases such as Graves' disease or Hashimoto's thyroiditis.
- These two diseases also cause the concentration of the TG molecule (thyroglobulin) to rise.
- Patients suffering from Graves' disease have elevated TSHR (TSH antibody receptor) values.
Step 3. Get your calcitonin measurement
This test is done to investigate thyroid problems more thoroughly. The concentration of this hormone can be high in the case of thyroid cancer (which could in turn be the underlying cause of various gland dysfunctions). It also arises in the presence of C-cell hyperplasia, another type of abnormal cell development in the thyroid.
Step 4. Get an ultrasound, biopsy, or thyroid scan to confirm certain conditions
Although blood tests can provide valuable data to the doctor for identifying and recognizing certain gland problems, in some cases more detailed investigations are needed to understand exactly what is going on; the doctor will inform you if other tests are necessary or not, such as ultrasound, biopsy or scintigraphy.
- Thanks to ultrasound, nodules can be visualized; if they are present, the sonographer can evaluate their contents to understand if they are solid or cystic masses (filled with fluid), since each type requires a different treatment. Ultrasound is also useful for monitoring any development or change in the growth over time.
- The biopsy involves the removal of a sample of the suspicious lump to rule out or confirm the presence of cancerous cells.
- Scintigraphy measures active (i.e. functional) areas of the gland, identifies inactive (non-functional) or hyperactive (with excessive activity) areas.
