What More Should I Know About Thyroid Blood Tests
Ranges noted here are approximate your providers may differ slightly. Its important that you remember abnormal readings do not necessarily mean a thyroid disorder is present, as each test can be affected by a variety of factors.
No preparation is required for these tests. They can be taken any time of day without fasting.
Questions For Your Doctor:
- Why do different doctors use different measurements for the normal ranges of thyroid hormones?
- What are the benefits and are there any risks of taking desiccated thyroid products?
- Is a TSH test diagnostic of hypothyroidism by itself?
This blog post was originally published by AutoimmuneMom.com and first published on Sep 17, 2012.
What Does The Thyroglobulin Antibody Mean
Thyroglobulin is a specific type of protein that is produced by the thyroid gland and is involved in the production of thyroxine. This serves an important role in maintaining healthy reserves of iodine and thyroid hormones in the body. In healthy individuals, the level of thyroglobulin is quite low and only in cases of malignancy does the level surge.
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Why Has The Doctor Asked Me To Under A Thyroid Profile Test
Individuals with abnormal thyroid levels tend to show these symptoms Unexplained weight changes either weight gain or weight loss Appetite changes Changes in levels of energy Anxiety and fast heartbeat Puffy face Sleep problems such as insomnia In addition to these, there are certain cases where thyroid hormone imbalance is seen as a result of autoimmune conditions such as Hashimotos disease. Here, the bodys immune system starts destroying healthy thyroid gland cells resulting in abnormal thyroid levels. If your doctor suspects any of these conditions as seen through the symptoms, he/she will ask you to undergo a thyroid profile test.
What Do The Results Mean
Your TSH test results can tell you if your thyroid is making too much or too little thyroid. But the test can’t explain why your TSH levels may be too high or too low.
If your test results aren’t normal, your provider will probably order other thyroid blood tests to find out what’s causing your thyroid problem. These blood tests may include:
- Thyroid antibodies test to help diagnose an autoimmune thyroid disorder, such as:
- Graves’ disease, the most common cause of hyperthyroidism
- Hashimoto’s disease, that the most common cause of hypothyroidism
In certain cases, an abnormal TSH result may be a sign of a pituitary gland problem, but this doesn’t happen often.
Learn more about laboratory tests, reference ranges, and understanding results.
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What Are Thyroid Blood Tests
Doctors use blood tests to check for thyroid or pituitary problems. In kids already diagnosed with thyroid or pituitary problems, the tests are used to guide treatment.
Commonly ordered thyroid blood tests include:
- : This is done to measure the blood level of the hormone T4 . It might be done in one or both of the following ways:
- total T4, which measures the entire amount of thyroxine in the blood, including the amount attached to blood proteins that help carry the hormone through the bloodstream
- free T4, which measures only the thyroxine that’s not attached to proteins. This is the part of T4 in the blood that affects how the body’s cells work.The results of the T4 blood tests can help diagnose hyperthyroidism or hypothyroidism and guide treatment.
In some cases, abnormal thyroid test results can be due to a medicine, an ongoing medical condition, or pregnancy. In these cases, there may be nothing wrong with the thyroid or pituitary glands themselves.
How Much Does The Test Cost
The cost of a thyroid panel depends on your insurance coverage and where the test is performed. If ordered by a doctor, insurance normally covers a thyroid panel except for any patient cost-sharing, such as copays or deductibles. Check with your health plan and health care provider for specific cost details.
A comprehensive thyroid panel is $189 from Testing.com.
Your insurance may cover thyroid panel testing in a doctors office, hospital or lab, but you will be responsible for all associate copays or deductible expenses.
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What Imaging Tests Do Doctors Use To Diagnose And Find The Cause Of Thyroid Disease
Your health care professional may order one or more imaging tests to diagnose and find the cause of thyroid disease. A trained technician usually does these tests in your doctors office, outpatient center, or hospital. A radiologist, a doctor who specializes in medical imaging, reviews the images and sends a report for your health care professional to discuss with you.
What Is It Used For
A TSH test is used to find out how well your thyroid is working. It can tell if you have hyperthyroidism or hypothyroidism in your blood. But a TSH test can’t show what is causing a thyroid problem.
If you take prescription thyroid hormone medicine because of hypothyroidism or because you had your thyroid removed, you’ll have regular TSH tests to check your thyroid hormone levels. TSH tests are also used to monitor your thyroid hormone levels after treatment for hyperthyroidism.
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How To Read Blood Test Results
While every laboratory or test-providing company may structure their result reports differently, they all must include the same components as mandated by federal legislation.
Some of that may be administrative content, such as the name of the person who did the blood test, the date the test was done, and the name of the doctor who ordered the test.
When it comes to understanding the results, you can look for the following :
- Quantitative test result. Results will be typically written out numerically in cases when the test measured the quantity of something. For example, if the test measured the amount of cholesterol in your blood.
- Abnormal markers. Often, a laboratory report will include some kind of marker to let you know if a result is outside the normal interval, and therefore abnormal. For example, you may see the letter H to indicate high, the letter L to indicate low, or the acronym WNL for within normal limits. You may see an asterisk and some additional comments in text if your results come out as highly abnormal. In this case, youll typically get a call from your doctor.
- Reference range. Every laboratory will have its own reference range for each type of test. Typically, this reference range will be written in your laboratory report next to the numerical value of your result so you are able to see where your result falls in the range.
To a blood test, the nurse or technician:
Thyroid Blood Tests: Types Symptoms And Interpreting Test Results
Your body has several glands to perform various body functions. The thyroid is a small gland located at the front of the neck, right at the spot where a bow tie would rest. It makes two types of thyroid hormones: triiodothyronine and thyroxine . It helps your body maintain its metabolic rate, and do numerous other things, including getting energy from food, growing, and going through sexual development.
The thyroid blood tests are simple lab tests that check if your thyroid is functioning right or not. In people who have already been diagnosed with thyroid problems, the tests are used to monitor and guide treatment.
Types of thyroid blood tests
- T4 test: This test measures the levels of the hormone T4 in your blood. It might be done in one or both of the following ways: Total T4, which measures the total amount of thyroxine in the blood. This includes the amount of T4 attached to blood proteins, which help the hormone move through the bloodstream and free T4, which measures only the amount of free thyroxine that is not attached to blood proteins.
- T3 test: This test measures the level of another major thyroid hormone. It again can be of two types: T3 totaI and free T3.
Symptoms and Diagnosis
- A low TSH level usually means you have high thyroid hormone levels in the blood , or an overactive thyroid. This implies that your thyroid gland is making excess hormones, and that is why the pituitary gland has reduced or stopped making and releasing TSH into your blood.
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What Do The Results From My Thyroid Function Test Mean
If a result in your thyroid function blood test is outside the normal range it can be flagged as high or low . Interpretation of the many variations in test results is complex and an abnormal result may not mean that anything is wrong. Other health conditions, extreme stress and pregnancy affect the levels of thyroid hormones, as well as medicines. Talking with your doctor about what your results mean for you is important.An abnormal TSH usually indicates a deficiency or an excess of thyroid hormones available to your body, but it does not indicate why this is happening. An abnormal TSH result is usually followed by additional testing of FT3 and/or FT4 to investigate the cause.A high TSH result:
- often means an underactive thyroid gland
- can also occur if you have an underactive thyroid gland and are receiving too little thyroid hormone medication
- can, in rare cases, indicate that you have a problem with your pituitary gland, eg, a tumour.
A low TSH result:
- can indicate an overactive thyroid gland or damage to your pituitary gland that is preventing it from producing TSH
- can also occur if you have an underactive thyroid gland and are receiving too much thyroid hormone medication.
Is There Anything Else I Need To Know About A Tsh Test
TSH levels may be high or low even when your thyroid gland is healthy. Serious illnesses not related to your thyroid may cause lower TSH levels for a short time. And TSH levels may be higher in people over age 80, even though they don’t have any thyroid problems.
Pregnancy also affects TSH levels. They are often a little low during the first three months. But sometimes, thyroid disease develops during pregnancy. If you develop thyroid disease during pregnancy, your provider will monitor your condition through your pregnancy and after your baby is born. That’s because hyperthyroidism, and less often, hypothyroidism, can continue after you give birth. If you have a history of thyroid disease, be sure to talk with your provider if you are pregnant or are thinking of becoming pregnant.
Newborn babies are routinely screened with a TSH test to see if they were born with hypothyroidism .
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What Are Normal T3 Levels
Normal value ranges for any lab test, including T3 tests, may vary slightly among different laboratories. Be sure to check your lab reports reference range on your results. If you have any questions about your results, ask your healthcare provider.
Normal T3 levels
Normal T3 level ranges vary based on age. In general, normal ranges for T3 for healthy people include:
- Children 1 to 5 years old: 106 203 nanograms per deciliter .
- Children 6 to 10 years old: 104 183 ng/dL.
- Children 11 to 14 years old: 68 186 ng/dL.
- Adolescents 15 to 17 years old: 71 175 ng/dL.
- Adults 18 to 99 years old: 79 165 ng/dL.
Normal free T3 levels
Providers dont usually order free T3 tests because theyre not as reliable, but it is possible to test these levels. In general, normal ranges of free T3 for healthy people include:
- Infants up to 3 days old: 1.4 5.4 picograms per milliliter .
- Infants 4 to 30 days old: 2.0 5.2 pg/mL.
- Babies 1 month to 1 year old: 1.5 6.4 pg/mL.
- Children 1 to 6 years old: 2.0 6.0 pg/mL.
- Children 7 to 11 years old: 2.7 5.2 pg/mL.
- Children 12 to 17 years old: 2.3 5.0 pg/mL.
- Adults 18 to 99 years old: 2.3 4.1 pg/mL.
Diagnosis Of An Underactive Thyroid Function Is Made Based On A Combination Of Thyroid Blood Test Results Symptoms And Several Other Factors
is evaluated and diagnosed by a physician, usually an endocrinologist or your primary care doctor. Symptoms, signs, andmore criticallyblood tests are taken into consideration when evaluating the possibility of an underactive , all of which help identify the cause and severity of the disease.
A diagnosis is reached after a thorough review of the patients personal medical and family histories, any risk factors, findings on physical examination, and the results of . There are several types of hormones checked in a blood test to assess your thyroid statusthe most definitive one is the . Often, physicians may decide to check the free , or T4, free T4 index, or total T4 to aid in the diagnosis.
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What Is Reverse T3
Reverse T3 is the inactive form of the actual T3 hormone. It has the same structure as that of T3 and the only difference is the position of the iodine atom in the molecular structure. This factor makes it biologically inactive. Measurement of this thyroid hormone is not considered clinically useful.
Where Can I Get Blood Work Done
There are different locations that offer laboratory services that include blood work. Most hospitals contain a laboratory that you can visit to get tests done. Some laboratories will have walk-in options. Others may require an appointment.
Additional locations for blood testing may include:
- Private laboratories. Hospitals may use private labs to offload some testing from their own laboratories, or in cases when a specialized test is needed. Often, health insurance plans will require you to use a specific laboratory that is in their network for the test to be covered.
- Point-of care. This describes situations when you may need to get a blood test wherever you are receiving medical care. In routine scenarios, this typically
Results may take anywhere from a few hours to a few days to become available. Heres an overview of how long some common tests may take:
- complete blood count : 24 hours
- basic metabolic panel: 24 hours
- complete metabolic panel: 24 to 72 hours
- lipid panel: 24 hours
Timing can depend on the specific lab where you get tested, and how many tests you get done at once. If you order multiple tests, you may not get the complete results until all of the tests are completed.
Sometimes a lab will only release results to your doctor, who reviews them and then releases them to you.
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What Is The Thyroid Profile Test
A thyroid profile test is a panel or series of blood tests done in order to understand whether or not your thyroid gland is functioning properly or not. The thyroid gland is probably the most critical endocrine gland in the human body that controls growth and metabolism. Both high and low thyroid hormone levels could affect several organ systems of the body and have chronic side-effects starting from weight disturbances to sleep disorders. A thyroid profile test checks the following thyroid hormones: TSH or thyroid secreting hormone T4
Thyroid Hormone Levels: T4 T3 T2 And T1
Your thyroid gland, which is situated in the lower front part of your neck, produces hormones that play a role in a variety of functions throughout the body, and impact many other hormones outside the thyroid. The two main states of dysfunction seen in thyroid conditions are called hyperthyroidism and hypothyroidism , and can be induced by a number of different individual thyroid disorders. There are many conditions involving this gland, each of which presents a unique pathology and characteristic clinical picture, usually seen when lab values for these hormones fall outside their normal ranges.
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What Are The Types Of Thyroid Disorders
Blood tests are used to diagnose hypothyroidism or hyperthyroidism. They do not point to a specific cause. In order to determine a cause of the thyroid abnormality, the doctor will consider the patient’s history, physical examination, and medical condition. Further testing might be used to isolate an underlying cause. These tests might include more blood testing for
- thyroid antibodies,
- ultrasound of the thyroid gland, or
If thyroid cancer is suspected and surgery may be required, your physician may ask for a blood test known as thyroglobulin.
- Thyroglobulin is a protein made only by thyroid cells.
- If the thyroglobulin level at baseline is detectable or elevated it can be used as a tumor marker.
- After a total thyroidectomy for cancer the level should fall to an undetectable range since the cells that make thyroglobulin have been removed.
- If the level remains detectable after surgery, there is a possibility of thyroid tissue elsewhere in the body, and metastatic disease should be considered.
- If the level is undetectable for a period of time after surgery and then starts to climb, a recurrence of the cancer – either at the primary site or elsewhere in the body should be considered.