What Is Hypothyroidism?

The thyroid is a type of gland in the body; it serves a specific purpose and is part of the endocrine system. The thyroid is located in the front portion of the neck, directly below the Adam’s apple, which is actually made up of thyroid cartilage. It consists of two sections, called lobes; these lobes are about the size of half of a large plum. The lobes are located on the left and right side of the trachea, connected by a small piece of tissue, known as the isthmus, which runs across the trachea. (Bayliss 1)
Like the other glands of the endocrine system, the thyroid manufactures certain chemicals, known as hormones, for the body. These hormones are secreted into the blood and affect the cells and tissues of the body. The hormones produced
by the thyroid are known as thyroxine (T4) and triiodothyronine (T3). These hormones regulate metabolic activity in the cells of the body, they also aid in both physical and mental development. They also regulate the rate of oxygen consumption and influence how food is metabolized. When these hormone levels get too low or too high, conditions such as hypothyroidism and hyperthyroidism can occur. (Bayliss 2-4)
When the thyroid gland is not producing enough of the T3 and T4 hormones, it causes a condition known as hypothyroidism. When this condition occurs in children, the causes, symptoms, and treatments vary from what would be the standard in adults. The main causes of this are development issues of the thyroid gland or autoimmune thyroiditis, also known as Hashimoto’s disease.
When hypothyroidism is caused by developmental issues of the thyroid, it is known as congenital hypothyroidism (CH).
This occurs during fetal development, but it may continue into adolescence. If CH is not caught via a newborn thyroid screening, because the thyroid gland is malformed, or developed enough to function in the drastically smaller body of an infant, it is possible for the condition to go unnoticed until around age 8. By this age, the maldeveloped gland is no longer able to keep up with the necessary hormone level that the patient’s body requires, and hypothyroidism gradually develops. (Bayliss 73) The symptoms of CH are often hard to detect and depend on the degree of thyroid deficiency. A baby suffering from CH will present with failure to thrive, excessive sleep, constipation, does not kick vigorously, often the abdomen is abnormally swollen, their cry may be hoarse, their hair may be short and coarse, the naval area may bulge outward or be ruptured, the tongue is abnormally large, and the face has a flat bloated look. Left untreated, CH will lead to poor neurological development, such as poor coordination, tremors, and unsteadiness. Once these symptoms have set in, the mental deficits may be permanent. (Bayliss
74-75)
The other cause of hypothyroidism is known as autoimmune thyroiditis, or Hashimoto’s disease (HD).
An autoimmune disease occurs when white blood cells, known as lymphocytes begin attacking other cells in the body. They see these cells as a “foreign” object and attack it, like they would an infection or other truly foreign body that has entered the body. Hashimoto’s disease is a significant cause of goitre, which is the term for an enlarged thyroid gland, in children age 10 and up. (Bayliss 62) The course of HD is usually prolonged over many years, at any stage it may appear to be lying dormant. The symptoms may differ based on the stage that the disease is at, and most patients seek medical attention in the later stages of the disease, after hypothyroidism has already developed. The first symptoms usually noticed are a slight enlargement of the thyroid gland; the gland slowly enlarges and will feel markedly soft and fleshy, unlike a healthy thyroid gland which is harder when palpated. While the patient’s blood will contain thyroid antibodies, the cells that are infiltrating the gland with lymphocytes and other related autoimmune cells, the patient will feel completely healthy and well. The gland may decrease slightly in size, as the disease progresses. For some, there will be weeks or months where the patient will feel some intermittent discomfort in the front of their throat and swallowing may be slightly painful at times. The lymphocytes are continuing to attack the
thyroid disuse and the inflammation caused by that is the reason for the discomfort and tenderness. The gland will now feel firmer, caused by the development of a lymphadenoid goitre, which occurs from the lymphocyte infiltration. The patient may experience short episodes of mild hypothyroid symptoms, this is called Hashitoxicosis. It is also possible for them to experience eye complications experienced, though this is very rare. Later, after a period of dormancy, the disease’s process continues. The gland may now have difficulty keeping up with the necessary levels of thyroid hormones the body needs, this will cause another gland known as the pituitary gland, to produce a hormone known as thyroid stimulating hormone (TSH) this hormone’s job is to stimulate the thyroid into producing the hormones it is responsible for producing. This is usually a failed effort due to the dwindling amount of normal thyroid tissue left in the gland. At this point in the diseases progression, a blood screen would show elevated thyroglobulin antibodies. Not long after this point, the thyroid has been destroyed. There is no viable thyroid tissue left and the patient develops hypothyroidism. At this stage, the thyroid gland, while no longer functional, may appear to be normal in size, enlarged, or so shrunken and fibrous that it can no longer be palpated. (Bayliss 64)