Recently I found out that a patient of mine was misdiagnosed with Hashimoto’s thyroiditis by her medical doctor. Most of my patients with Hashimoto’s and Graves’ disease who see me for the first time have already been diagnosed with an autoimmune thyroid condition. And both conditions usually aren’t too difficult to diagnose. But I’m sure there are some people who don’t understand how both of these autoimmune thyroid conditions are diagnosed, and they simply take the word of their endocrinologist or primary care physician. And so I figured I’d put together a post that discusses how both of these conditions are diagnosed.
What’s disturbing is that the person who was misdiagnosed with Hashimoto’s wasn’t even hypothyroid at the time of her diagnosis, yet she was put on thyroid hormone replacement. Now to be fair, many people with Hashimoto’s thyroiditis have subclinical hypothyroidism [1], where their TSH is elevated and their thyroid hormone levels are within the lab reference range. But in this person’s case, her TSH was 1.18 uIU/mL at the time of her diagnosis. In addition, she didn’t have any thyroid antibodies [2] tested. Yet she was told she had Hashimoto’s and was put on thyroid hormone replacement, which she was taking since 2014.
Although it’s upsetting that this person was misdiagnosed with Hashimoto’s, I think it’s safe to say that most people who were told they have an autoimmune thyroid condition have received the appropriate diagnosis. But it’s also safe to say that this person isn’t the only one who has been misdiagnosed with an autoimmune thyroid condition. And even if only a small percentage of people are misdiagnosed every year, I want to try to reduce the incidence of this, which is why I’m putting together this post.
Diagnosing Hashimoto’s Thyroiditis
According to the American Thyroid Association, this is how Hashimoto’s thyroiditis is diagnosed (1) [3]:
“The diagnosis of Hashimoto’s thyroiditis may be made when patients present with symptoms of hypothyroidism, often accompanied by a goiter (an enlarged thyroid gland) on physical examination, and laboratory testing of hypothyroidism, which is an elevated thyroid stimulating hormone (TSH) with or without low thyroid hormone (free T4) levels. TPO antibody, when measured, is usually elevated. Occasionally, the disease may be diagnosed early, especially in people with a strong family history of thyroid disease. TPO antibody may be positive, but thyroid hormone levels may be normal or there may only be isolated mild elevation of serum TSH. Symptoms of hypothyroidism may be absent.”
So let’s break down their diagnosis:
- Patient presents with symptoms of hypothyroidism, often accompanied by an enlarged thyroid gland (goiter)
- Laboratory testing shows an elevated TSH, with or without low thyroid hormone levels
- TPO antibodies are usually elevated
They also mention that when diagnosed early, TPO antibodies may be positive, but thyroid hormone levels might be normal or there may only be a mild elevation of serum TSH, and that symptoms of hypothyroidism might be absent. So you don’t need to have symptoms of hypothyroidism to be diagnosed, and the TSH might be slightly elevated, but TPO antibodies [4] usually are positive. Unfortunately they didn’t mention anti-thyroglobulin antibodies, which are also associated with Hashimoto’s, as there are cases when TPO antibodies are negative but someone has positive anti-thyroglobulin antibodies [5].
Is a Thyroid Ultrasound Necessary?
Some sources will also mention the value of doing a thyroid ultrasound [6] in coming up with a diagnosis. One study showed that reduced thyroid echogenicity was a valid predictor of thyroid autoimmunity (2) [7]. However, one can argue that positive ultrasound findings aren’t necessary to diagnosis Hashimoto’s if someone has an elevated TSH and either elevated TPO and/or thyroglobulin antibodies.
Summary of Hashimoto’s Thyroiditis Diagnosis
So when putting everything together that I mentioned above, it should be clear how Hashimoto’s thyroiditis is diagnosed, as the following two factors both need to be present:
- Elevated TSH
- Elevated thyroid peroxidase antibodies and/or anti-thyroglobulin antibodies
Normal TSH In the Presence of Elevated Thyroid Antibodies
But what if someone has elevated thyroid antibodies but their TSH is perfectly fine? Or if their TSH is within the laboratory reference range, but higher than optimal, yet the person has one or more elevated thyroid antibodies? Well, from a medical standpoint neither of these patients will probably be diagnosed with Hashimoto’s, although they do have the antibodies associated with Hashimoto’s. In this situation most medical doctors won’t give thyroid hormone replacement, but even if the person doesn’t need to take thyroid hormone replacement, it doesn’t mean that the immune system should be ignored.
In fact, for those who have read my book “Hashimoto’s Triggers [8]”, the very first chapter discusses the timeline of Hashimoto’s. In this chapter I discuss the following four stages of Hashimoto’s. I’ll list the stages below, but you can actually access the first chapter of my book for free by visiting Amazon.com and searching for my book on Hashimoto’s (or you can click here [8]), and on the left side of the page click on “Look Inside”, and you’ll be able to check out the first chapter of my book.
The Autoimmunity Timeline
Stage #1: Pre-autoimmunity. This is the most critical time to prevent an autoimmune condition from developing. The pre-autoimmune stage is essentially when, over time, a person’s body becomes more susceptible to developing autoimmunity.
Stage #2: Silent autoimmunity. In this stage, the autoimmune process has already started. However, there has been very little or no tissue damage (i.e., to the thyroid gland), and, therefore, no symptoms are present, and the basic thyroid panel results are negative at this point (i.e., normal TSH and thyroid hormone levels). The person is usually in the silent stage for many years.
Stage #3. Symptoms are present with some tissue damage. Although stage #2 might involve some tissue damage, it’s minimal, but stage #3 is when this damage reaches the point where the person begins to experience symptoms. Once again, it can take many years for this to happen.
Stage #4. Symptoms are present and there is greater tissue loss. This is the “final” stage of autoimmunity, as it’s when the person’s symptoms will usually worsen, there is greater tissue loss, and the thyroid blood tests are positive. Although some people might be diagnosed with an autoimmune thyroid condition in stage #3, many people with Hashimoto’s won’t be diagnosed until they reach stage #4.
So when someone has a normal TSH and elevated thyroid antibodies, this is considered to be stage #2, which is silent autoimmunity. Some may say that there is no concern because the person might never progress to stage #3. While this may be true, many people WILL progress to stage #3, and eventually stage #4. As a result, I think it’s crazy to ignore the immune system if someone has elevated thyroid antibodies, even if the TSH and thyroid hormones are within the optimal range.
By the way, if you want to learn more about the optimal reference ranges of the TSH and thyroid hormone levels, last month I released a video entitled “How To Read Your Thyroid Panel Results [9]”, where I discuss the optimal reference ranges. I also created separate videos you might want to check out on the three main types of thyroid antibodies.
Diagnosing Graves’ Disease
So let’s take a look at how the American Thyroid Association says that Graves’ disease is diagnosed (3) [10]:
“The diagnosis of hyperthyroidism is made on the basis of your symptoms and findings during a physical exam and it is confirmed by laboratory tests that measure the amount of thyroid hormones (thyroxine, or T4, and triiodothyronine, or T3) and thyroid-stimulating hormone in your blood. Clues that your hyperthyroidism is caused by Graves’ disease are the presence of Graves’ eye disease and/or dermopathy, a symmetrically enlarged thyroid gland and a history of other family members with thyroid or other autoimmune problems, including type 1 diabetes, rheumatoid arthritis, pernicious anemia, or painless white patches on the skin known as vitiligo.
The choice of initial diagnostic testing depends on cost, availability and local expertise. Measurement of antibodies, such as thyrotropin receptor antibodies (TRAb) or thyroid stimulating immunoglobulins (TSI), is cost effective and if positive, confirms the diagnosis of Graves’ disease without further testing needed. If this test is negative (which can also occur in some patients with Graves’ disease), or if this test is not available, then your doctor should refer you to have a radioactive iodine uptake test (RAIU) to confirm the diagnosis.”
Their diagnosis explanation is a bit lengthy, as they start out by explaining how hyperthyroidism is diagnosed, and then they give “clues” on how your hyperthyroidism is caused by Graves’ disease (i.e. thyroid eye disease, dermopathy), before finally mentioning that Graves’ disease is either diagnosed by positive TRAB or TSI, or by a radioactive iodine uptake test (if the thyroid antibodies are negative). One thing I’m happy that they mentioned is that the radioactive iodine uptake test should be done only if the thyroid antibodies are negative. Unfortunately many endocrinologists recommend this test to all of their Graves’ disease patients.
About the Radioactive Iodine Uptake Test
As I just mentioned, the radioactive iodine uptake test [11] is commonly recommended by endocrinologists to aid in the diagnosis of Graves’ disease. This test involves taking a very small amount of radioactive iodine, and the scan shows how much of the radioactive iodine is absorbed by the thyroid gland. A high uptake reading is usually present in Graves’ disease, although it can also be high in toxic multinodular goiter.
So what’s the problem with having everyone with Graves’ disease do this test? Well, the good news is that the amount of radioactive iodine is so small that it won’t cause significant damage to the thyroid gland. However, if the person has hyperthyroidism and also tests positive for TRAB and/or TSI, then this confirms that the person has Graves’ disease. Some endocrinologists will argue that the RAI uptake test is still necessary to see if there are hot or cold nodules. Thyroid nodules that absorb the radioactive iodine (hot nodules) are usually not malignant, while thyroid nodules that do not absorb the radioactive iodine (cold nodules) have a 5% chance of being malignant (4) [12].
So the radioactive iodine uptake test can’t reveal if someone has cancerous thyroid nodules. If someone has hot nodules they probably are benign, and if someone has cold nodules there is a slightly higher risk of the thyroid nodule being cancerous, but still only 5%. So to me it makes sense to pass on this test and do a thyroid ultrasound, which also won’t confirm if thyroid nodules are malignant or benign, although sometimes you can get a good idea by the characteristics of the nodule on an ultrasound.
What If Graves’ Disease Antibodies and The RAI Uptake Test are Both Negative?
If antibodies associated with Graves’ disease are negative and the RAI uptake test isn’t elevated then the person probably doesn’t Graves’ disease. If they have overt hyperthyroidism then they might have toxic multinodular goiter or subacute hyperthyroidism. For those who have been diagnosed with toxic multinodular goiter, in the near future I’m going to be creating an updated blog post on this topic.
But one thing I didn’t mention was the role of eye symptoms in diagnosing Graves’ disease. Of course there are many different types of eye symptoms one can have, and just because someone has hyperthyroidism in the presence of certain eye symptoms doesn’t confirm that they have Graves’ disease. For example, many people have dry eyes [13]. However, if someone has hyperthyroidism in the presence of eye bulging, eye swelling, or other more extreme symptoms, this probably means the person has Graves’ disease, even without testing the thyroid antibodies or doing an RAI uptake test.
So let’s take an example of someone who has hyperthyroidism, along with the symptoms of thyroid eye disease [14], yet the antibodies associated with Graves’ disease are negative. Should this person get the RAI uptake test to confirm the presence of Graves’ disease? It admittedly is a tougher call in this situation, but in my opinion I’d still say “no”, as if the person has hyperthyroidism AND the symptoms of thyroid eye disease then they probably have Graves’ disease.
Graves’ Disease vs. Hashitoxicosis
One other thing I should mention is that every now and then I’ll come across someone with hyperthyroidism and their thyroid stimulating immunoglobulins are negative, yet they have positive TPO and/or thyroglobulin antibodies. If this person has thyroid eye disease then they probably have Graves’ disease, as it’s very common for people with Graves’ disease to also have TPO antibodies, and many also have thyroglobulin antibodies. But one also has to rule out hashitoxicosis [15], which I discussed in a 2019 blog post. I won’t get into detail about hashitoxicosis here, as you can read the blog post for more information, but I will say that people with hashitoxicosis will typically have hyperthyroidism with elevated TPO and/or thyroglobulin antibodies, and they will have a normal TRAB and TSI. If they do a radioactive iodine uptake test this will be negative.
Summary of Graves’ Disease Diagnosis
So in order for Graves’ disease to be diagnosed, the following need to be present:
- Depressed TSH
- Elevated TSH receptor antibodies and/or thyroid stimulating immunoglobulins
However, Graves’ disease is also is commonly diagnosed by hyperthyroidism and an elevated radioactive iodine uptake test. And as I also mentioned, if someone has hyperthyroidism and thyroid eye disease, there is a pretty good chance they have Graves’ disease, even without testing the thyroid antibodies or doing the RAI uptake test.
Subclinical vs. Overt Hyperthyroidism
You may have noticed that I didn’t include elevated thyroid hormone levels in my summary. And the reason for this is because some people have “subclinical Graves’ disease” (5) [16], where they have a depressed TSH, an elevated TRAB or TSI, but their thyroid hormones are normal. This isn’t too common, although I’ve had some patients with subclinical Graves’ Disease. But once again, regardless of whether someone has subclinical Graves’ disease or subclinical Hashimoto’s thyroiditis, you want to address the autoimmune component. I also should mention that some people have subclinical hyperthyroidism without positive thyroid autoantibodies.
How Long Have You Been Diagnosed With An Autoimmune Thyroid Condition?
I’d like to know how long you have been diagnosed with an autoimmune thyroid condition for, and so please let me know in the comments below. And while I’m hoping that nobody reading this has been misdiagnosed, if you were and would like to share your story please feel free to post it below so that others can learn from your experience. Thank you!