Autoimmune disorders are multi-faceted. As such, they can be exceptionally difficult to diagnose. Hashimoto’s Thyroiditis is one of many autoimmune conditions that poses its own set of challenges.
As an autoimmune thyroid disorder, Hashimoto’s may be recognized in a variety of ways. The most common and relied on method is testing the amount of circulating thyroid antibodies. However, Hashimoto’s does not always cause a change in antibody count. Ignorance of this fact can result in a patient suffering from an undiagnosed case of Hashimoto’s. To better diagnose Hashimoto’s, it is important to have a good understanding of the condition itself, be familiar with common testing practices, and learn why antibodies should not be relied on as the sole method of diagnosis.
What is Hashimoto’s Thyroiditis?
The immune system is the body’s first line of defense and is an essential part of wellness. When working as intended, the immune system identifies potential threats including toxins, viruses, and bacteria, and produces antibodies to eliminate the offending substances. The immune system also identifies and eliminates dead or decaying cells and tissues that can cause disease if left unattended. Autoimmune disorders can disrupt the identification process resulting in improper targeting and destruction of healthy cells and tissues.
Hashimoto’s occurs when the immune system wrongly identifies proteins in the thyroid gland as a threat to the body’s health. This results in the immune system releasing white blood cells and lymphocytes to attack healthy thyroid tissue. Hashimoto’s is one of the leading causes of hypothyroidism or reduced thyroid function. However, as antibodies assault the thyroid gland, thyroid hormones are released as tissue is destroyed. This can cause a temporary spike in thyroid hormone triggering symptoms similar to hyperthyroidism or hastened thyroid function. This is known as Hashitoxicosis. Ultimately, the damage done to the thyroid becomes so severe that the gland is unable to produce adequate thyroid hormone to support proper bodily function resulting in hypothyroidism.
Hashimoto’s develops over an extended period and symptoms typically do not appear until much later into its development. Because of this, Hashimoto’s is often not recognized until thyroid antibodies have been released and significant damage has already been done to the thyroid. On average, it takes about 10 years from the initial autoimmune attack on the thyroid for patients to be diagnosed with Hashimoto’s. Part of the reason for this is inadequate testing practices.
Testing for Hashimoto’s
Thyroid disease of any type is often identified through testing of thyroid hormones such as TSH, T4, T3, and Reverse T3 – get a sample lab slip here. An imbalance of these important hormones may indicate thyroid dysfunction. In the case of autoimmune thyroid disease such as Hashimoto’s, doctors often rely solely on thyroid antibodies such as thyroid peroxidase (TPO) antibody and thyroglobulin (Tg) antibody for diagnosis.
TPO is an enzyme used in the production of thyroid hormones and a prominent autoantigen in autoimmune thyroid disease. Approximately 95 percent of Hashimoto’s patients exhibit elevated TPO levels. Thyroglobulin is protein found in the thyroid gland and used in the synthesis of thyroid hormone. As inflammation and damage to the thyroid gland increases, thyroglobulin can leak into the bloodstream. This causes greater production of Tg antibodies. It is estimated that between 20 to 50 percent of Hashimoto’s patients have elevated Tg antibodies.
If TPO and Tg antibodies are elevated, it is a sure sign that an autoimmune thyroid disorder is present. However, Hashimoto’s may be present if there is not an increase in thyroid antibodies. Some patients may even have reduced levels of thyroid antibodies. It is estimated that five percent of Hashimoto’s patients do not have measurable antibodies, meaning that the condition can be easily overlooked if antibodies are the only metric used for diagnosis.
Why Aren’t My Antibodies Increased?
It is estimated that between five and 10 percent of Hashimoto’s patients do not exhibit increased levels of thyroid antibodies. This is known as seronegative autoimmune thyroiditis. Patients belonging to this group will not have circulating and easily measurable thyroid antibodies. Due to an over-reliance on assessing antibody levels for diagnosing autoimmune thyroid disease, these individuals often go undiagnosed despite having a fully developed case of Hashimoto’s.
There are multiple reasons why a Hashimoto’s patient may not present an increase in thyroid antibodies.
Hashimoto’s Is Too Early in Development
Early stage Hashimoto’s is less likely to trigger an increase in thyroid antibodies. One study found that the increase in antibodies indicative of Hashimoto’s only appears after significant inflammation and damage has been done to the thyroid. Therefore, early diagnosis is more difficult if antibodies are the only method used to test for it. As Hashimoto’s worsens, thyroid antibody levels tend to increase making diagnosis easier. However, at that point the damage to the thyroid is irreversible and has likely reached a severe stage.
The Immune System is Fatigued or Overworked
A weak immune system may not be able to provide antibodies during an immune response. In such a situation, there is little change in antibody production, meaning antibody prevalence will remain at seemingly normal level. This is more common among patients who have had Hashimoto’s or another autoimmune condition for an extended period. As the immune system relentlessly fights against invaders and harmful substances it can become fatigued and less-responsive. Only after immune function is restored will antibody count increase allowing for more expedient and accurate diagnosis of Hashimoto’s via thyroid antibodies.
The Immune System is Imbalanced
The immune system is composed of two primary components: TH1 and TH2. TH1 is the immediate immune response that assaults invaders as soon as they are recognized. TH2 delays its response and produces antibodies to resolve the issue. When working correctly, the immune system employs both of these elements to great effect. Hashimoto’s often causes an imbalance of TH1 and TH2 immunity that increases the TH1 response and suppresses TH2 activity. The result is greater inflammation and damage done to the thyroid with lower prevalence of thyroid antibodies. This causes significant thyroidal disruption without the telltale signs of increased antibody prevalence.
Always Test Thoroughly for Hashimoto’s
Under normal circumstances, treating Hashimoto’s is an exceptionally difficult task. If it is undiagnosed, it becomes virtually impossible. Sadly, many people with Hashimoto’s are unaware of their condition due to an over-reliance on thyroid antibodies for diagnosis. Although an increase in thyroid antibodies is a sure sign that a thyroid autoimmune condition has developed, Hashimoto’s may be present without a notable change to thyroid antibody prevalence. To more effectively identify and treat Hashimoto’s it is essential that we test thoroughly for signs of autoimmune and thyroid dysfunction and do not rely solely on thyroid antibodies.
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