Should Predictive Autoantibody Screening Be Utilized?

Autoimmune thyroid conditions such as Graves’ Disease and Hashimoto’s Thyroiditis are characterized by the presence of autoantibodies. And with both conditions, these antibodies appear before there are any changes in the TSH, thyroid hormone levels, or the person’s symptoms. This is the case with all autoimmune conditions, as the autoantibodies are the first thing to develop. And there is evidence that in some cases these autoantibodies can appear up to ten years before they result in changes in the labs and/or symptoms. Based on this information it might make sense to do preventative screening on everyone, including children, in order to determine if they have autoantibodies.

Most, if not all people who develop a condition such as Graves’ Disease or Hashimoto’s Thyroiditis have a genetic predisposition for this condition. However, just having a genetic marker for an autoimmune thyroid condition doesn’t mean a person will develop this condition, as something triggers the autoimmune response. Once this happens the person will develop autoantibodies, which eventually will lead to changes in the TSH and/or thyroid hormone levels. The person very well might develop symptoms before these values go outside of the lab reference range, or they might not become symptomatic until these are actually outside of the reference range.

Silent Autoimmunity Shouldn’t Be Overlooked

Recently I was reading an article entitled “New Predictors of Disease” by Aner Louis Notkins (1). In this article it was discussed how autoantibodies can be manufactured many years before enough tissue damage occurs to cause the development of symptoms. So let’s take a look at a condition such as type 1 diabetes, which involves destruction of the beta cells of the pancreas. When I was teenager I had a friend who developed type I diabetes. He was around 13 years old when he was diagnosed with this condition, but just like others with type 1 diabetes, his body began forming these antibodies many years earlier. It was only at the point where sufficient damage to his pancreas occurred that he became symptomatic.

The same concept applies to Hashimoto’s Thyroiditis. The primary autoantibodies associated with this condition are thyroid peroxidase antibodies and thyroglobulin antibodies. When someone begins developing symptoms associated with this condition, in most cases these thyroid antibodies have developed many years before the onset of symptoms. In fact, it usually takes years before sufficient damage to the thyroid gland occurs to cause an increase in the TSH, and it usually takes even more time than this before the thyroid hormone levels become depressed.

Graves’ Disease is somewhat different than many other autoimmune conditions. For example, most autoimmune conditions result in the destruction of tissue. As mentioned earlier, type 1 diabetes results in destruction of the beta cells of the pancreas. Hashimoto’s Thyroiditis results in destruction of the thyroid gland. The condition rheumatoid arthritis attacks and damages the synovial joints. Multiple sclerosis involves destruction of the myelin sheath of the brain. However, the TSH receptor antibodies associated with Graves’ Disease apparently don’t damage or destroy any bodily tissues. They either bind to or stimulate the TSH receptors. And when compared to other autoimmune conditions, chances are it doesn’t take nearly as long before someone with these antibodies experiences symptoms and/or changes in the TSH and thyroid hormone levels. However, it’s not uncommon for people with Graves’ Disease to also have thyroid peroxidase antibodies, and some will have thyroglobulin antibodies as well.

What Value Can Predictive Screening Provide?

I realize that many people reading this already have an autoimmune thyroid condition. However, there are a few factors to consider when thinking about whether you should consider predictive screening:

1) People with one autoimmune condition are more likely to develop another one. Research clearly shows that those people who have one autoimmune condition are more likely to develop additional autoimmune conditions. So for example, someone with Graves’ Disease or Hashimoto’s Thyroiditis has a greater likelihood of developing conditions such as Rheumatoid arthritis, Lupus, and other autoimmune conditions. In fact, if you currently have an autoimmune thyroid condition then there is the chance you have autoantibodies for another condition.

2) One of your family members might have a genetic predisposition for an autoimmune thyroid condition (or a different autoimmune condition). If you have any type of autoimmune condition and have children, then there is a greater chance of them having a genetic marker for the same condition. And just because they have a normal TSH and normal thyroid hormone levels and are asymptomatic doesn’t mean they don’t have any autoantibodies which are currently causing damage to their thyroid gland. Or they might have the autoantibodies for a different condition.

So does this mean that everyone should be routinely screened for the presence of autoantibodies? The problem is that such testing can be expensive. Just testing alone for the presence of thyroid antibodies can be very pricey. And if you want to do more than just test for thyroid autoantibodies then it can become extremely expensive. The company Cyrex Labs has a panel called the “Multiple Autoimmune Reactivity Screen”, which tests for about two dozen common autoantibodies, such as thyroid peroxidase antibodies, thyroglobulin antibodies, parietal cell antibodies, islet cell antibodies, myelin antibodies, and numerous other autoantibodies. But this test costs hundreds of dollars, and one might spend even more at a local lab to obtain all of these different autoantibodies. And even if you have good health insurance coverage, it is unlikely to cover all of these autoantibodies on a routine basis (i.e. annually or once every couple of years).

Can Genetic Testing Be Utilized?

Another option to consider is to do genetic testing to see if one has the genetic markers for certain autoimmune conditions. And then if they do test positive they can selectively obtain testing for autoantibodies. For example, if someone has the genetic markers for Celiac disease (HLA-DQ2 and/or HLA-DQ8), because they have an increased risk of developing Celiac disease they might choose to obtain a Celiac panel. Similarly, if they have one or more genetic markers for other autoimmune conditions then they can test for those specific conditions. Keep in mind that having a genetic marker for a specific condition doesn’t guarantee someone will have autoantibodies for that condition.

However, one important piece of information you need to understand is that an autoimmune condition can be triggered at anytime. For example, let’s talk about Celiac disease again. If someone has the genetic markers for this condition but the autoantibodies on the Celiac panel are negative, this doesn’t mean that some environmental factor won’t trigger an autoimmune response in the future, thus leading to the development of this condition. And this of course is true with any autoimmune condition.

Because of this fact, one ideally would want to do genetic testing to see which autoimmune conditions they’re susceptible to, and then if they have certain genetic markers they can routinely test for the presence of autoantibodies specific to these conditions. So for example, if they have the genetic markers for Celiac disease, multiple sclerosis, and Graves’ Disease, then it probably would be a good idea to get these autoantibodies tested at least every few years. While this won’t be as expensive as testing for all of the different autoantibodies, or even the most common autoantibodies, it still can be expensive. And getting the genetic testing can also cost a decent amount of money.

In addition, unlike Celiac Disease, there aren’t clear genetic markers for Graves’ Disease and Hashimoto’s Thyroiditis. In Graves’ Disease, the genetic marker HLA-DR3 was reported by several studies as the primary marker associated with this condition, while in Hashimoto’s Thyroiditis, no consistent associations were observed (2).

What’s The Purpose Of Doing Predictive Autoantibody Screening?

Another factor to consider is the approach one will take when someone does predictive screening and tests positive for autoantibodies. There really is no purpose to spend the money on genetic testing and/or autoantibody panels if you’re not going to do anything to address the autoimmune response. The primary reason to do such testing is to find out if one has elevated antibodies so that they can attempt to suppress the autoimmune component before sufficient tissue damage occurs, leading to symptoms and/or changes in other values.

In summary, with autoimmune conditions, the autoantibodies appear before the onset of symptoms and deviations in lab values. And in some cases, these autoantibodies can develop many years before noticeable changes take place. This is definitely the case with Hashimoto’s Thyroiditis, as some people have positive thyroperoxidase antibodies and/or thyroglobulin antibodies for many years before sufficient damage to the thyroid gland occurs which results in changes to the TSH, thyroid hormone levels, and/or the onset of symptoms. With Graves’ Disease this might not be the case, as while TSH receptor antibodies do develop before the TSH and thyroid hormone levels get out of range, these antibodies most likely aren’t high for many years before one notices these changes. But since autoimmunity is prevalent, doing predictive autoantibody screening or genetic testing for those conditions which result in tissue damage or destruction might be something to consider.