How Having Hypothyroidism Actually Skews Thyroid Lab Testing: Part II

In a previous post, I talked about how hypothyroidism causes you to hold onto water and can give you a false reading of thyroid hormone levels. Your doctor could look at these skewed levels on the thyroid lab testing and misdiagnose you as falling into normal ranges in the thyroid hormone levels.

To continue that conversation, we are going to look at another portion of the thyroid panel that doctors often look at that give a false presentation: T4 and T3.

T4 and T3 lab test shows how much T4 and T3 are present in the blood at that instant in time. It does this by looking at the amount of T4 and T3 per volume of blood. Since hypothyroidism causes you to retain water by causing an increased production in mucin, water is sucked out of the blood and into the extracellular matrix.

Now there is a lowered blood volume, but still the same amount of T4 and T3 in the blood stream. This gives you a false reading of the thyroid hormone levels by making the T4 and T3 value seem more elevated than what is actually the case. This might even push the numbers into the normal range, making your doctor believe that everything is normal.

This is one more example that demonstrates the point that thyroid hormone levels through lab analysis need to be interpreted by comparing the results to the additional testing (like for sex hormones, adrenal stress test, nutrient levels, etc), family history, symptoms and physical presentation. This is the only way that the lab results gives any pertinent information.

technorati tags: T4 andT3 thyroid hormone levels