THYROID DISORDERS

Thyroid is an endocrine gland situated at the root of neck on either side of the trachea. It has two lobes, connected by a structure called isthmus. The thyroid secretes two major hormones, thyroxine and tri-iodothyronine, commonly called T 4 and T3 respectively. Both of these hormones profoundly increases the metabolic rate of the body. Thyroid secretion is controlled primarily by thyroid stimulating hormone (TSH) secreted by the anterior pituitary gland. The thyroid gland also secretes calcitonin, an important hormone for calcium metabolism.

The two main types of thyroid diseases are hypothyroidism and hyperthyroidism. Increased secretion of thyroid hormone is called hyperthyroidism. Decreased secretion of thyroid hormone is called hypothyroidism. Hypothyroidism leads to myxedema in adults and cretinism in children.

Thyroid diseases can affect anyone i.e, men, women, infants, teenagers and the elderly. It can be present at the time of birth or it can develop as you age often after menopause in women. A woman is about 5-8 times more likely to be diagnosed with a thyroid condition than a man. You may be at a higher risk of developing a thyroid disease if you have a family history of thyroid disease , have a medical condition includetype1 diabetes, pernicious anemia, primary adrenal insufficiency, lupus, rheumatoid arthritis etc., taking a medication which is high in iodine, after the age of 60 especially women.

HYPOTHYROIDISM

One of the most common problems affecting the thyroid gland is hypothyroidism. This occurs when the gland stop making enough hormone. The most common cause of this condition is Hashimoto's thyroiditis- an autoimmune disorder that ultimately causes the gland to stop working. Symptoms of hypothyroidism include

• Anemia

• Fatigue

• Mental sluggishness

• Tiredness

• Dry skin and hair

• Weight gain

• Cold Intolerance

• Constipation

• Sleepy all the time

• Frequent and heavy menstruation

• Hoarse voice

HYPERTHYROIDISM

Increased secretion of thyroid hormone is called hyperthyroidism. It is usually caused by an autoimmune disease called Grave’s disease or by a metabolically active thyroid nodule that is making too much hormone. Symptoms of hyperthyroidism include

• Weight loss

• Rapid heart rate

• Increased sweating

• Diarrhoea

• Anxiety, irritability and nervousness

• Goitre -enlarged thyroid gland

• Muscle weakness and tremors

• Irregular menstruation or amenorrhea

• Vision problems or eye irritation

• Intolerance to heat

• Exophthalmos

HASHIMOTO’S DISEASE

Hashimoto’s disease is an autoimmune disorder affecting the thyroid gland. An autoimmune disorder is an illness caused by the immune system attacking the healthy tissues. Hashimoto’s disease is also known as Hashimoto’s thyroiditis or chronic autoimmune thyroiditis. In Hashimoto’s disease, immune system cells leads to the death of the thyroid- hormone producing cells ,which results in a decline in the hormone production(hypothyroidism).The disease progresses slowly over the years .Eventually the decline in thyroid hormone production can result in symptoms like fatigue and sluggishness, dry skin, increased sensitivity to cold, increased sleepiness, constipation, irregular menses, puffy face, brittle nails etc .

Causes: genetic factors, environmental triggers such as infection, stress or radiation exposure, interaction between environmental and genetic factors.

Risk factors:

• Sex- women are more likely to get Hashimoto’s disease.

• Age- it can occur at any age but more commonly occurs during middle age.

• Other autoimmune disease- having another autoimmune diseases such as rheumatoid arthritis,type1 diabetes, lupus increases your risk of developing Hashimoto’s disease.

• Genetic and family history

• Pregnancy

• Excessive iodine intake

• Radiation exposure

Complications of Hashimoto’s disease include goitre, heart problems, mental health issues, sexual and reproductive dysfunction, poor pregnancy outcome, myxedema etc.

GOITER

Goiter means enlargement of thyroid gland. It occurs in both hypothyroidism and hyperthyroidism. A goiter may be an overall enlargement of the thyroid or it may be the result of irregular cell growth that forms one or more lumps(nodules) in the thyroid. The most common cause of goiter is the lack of iodine in the diet.

Most people with goiter have no signs or symptoms other than a swelling at the base of neck. Other signs or symptoms depend on whether thyroid function changes, how quickly the goiter grows and whether it obstructs breathing.

Goiter in hyperthyroidism is called Toxic Goiter. It is the enlargement of thyroid gland with increased secretion of thyroid hormones caused by thyroid tumour. Goiter in hypothyroidism is called Non-toxic goiter. It is the enlargement of thyroid gland without increase in hormone secretion. It is also called as Hypothyroid goiter.

Causes- Iodine deficiency, Hashimoto’s disease, Graves disease, Thyroid nodules, Thyroid cancer, Pregnancy, Inflammation.

Risk factors:

• A lack of dietary iodine

• Women are more likely to develop goiter

• Pregnancy and menopause

• Age- more common after the age of 40

• Family medical history- history of goiters or other thyroid disorders in family members.

• Radiation exposure

DIAGNOSIS OF THYROID DISEASES

1. BLOOD TEST

2. IMAGING TEST (USG)

3. PHYSICAL EXAMINATION

Thyroid blood tests are used to tell if your thyroid gland is functioning properly by measuring the amount of thyroid hormones in your blood. The specific blood test that will be done to test your thyroid include TSH,T3,T4,free T3, free T4,thyroid antibodies, and thyroglobulin.