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Goiter (Iodine deficiency syndrome)

It is a non-inflammatory and non-neoplastic enlargement of the thyroid gland. It is an abnormal enlargement of your thyroid gland. It located at the base of the front side of the neck just below Adam’s apple.

Type of goiter – There are different types of goiter:

(a) Endemic colloid goiter:

Requirement of iodine: 50 gram / year, and >50 gm / day

Definition: Greatly enlarged thyroid gland due to lack of dietary iodine is known as endemic colloid goiter.

Cause –

Some areas in the world do not have a sufficient amount of iodine to the soil. This results in a lack of iodine in food. The most common cause of goiters worldwide is a lack of iodine in the diet.

Mechanism:

Lack of iodine in diet T3, T4, a prohormone to stop production of TSH → TSH →↑ thyroglobulin production → more thyroglobulin in the follicles → the gland grows larger and larger.

The follicles become tremendous in size, and the thyroid gland may increase to 10 to 20 times normal size.

(b) Idiopathic nontoxic colloid goiter:

It occurs usually in mild thyroiditis, which causes slight hypothyroidism. It leads to secretion of TSH progressive growth of the non-inflamed and portion of the gland. So some portion of the gland is growing while other portions are being destroyed by thyroiditis.

(c) Goitrogenic substances caused goiter:

Some foods contain a goitrogenic substance that has propylthiouracil – type antithyroid activity thus also bading to TSH – stimulated enlargement of thyroid gland. This type again found in some varieties of turnips and cabbages.

Symptoms – When signs and symptoms do occur they may include: A visible swelling at the base of your neck, Coughing, Hoarseness, Difficulty breathing etc.

Treatment – Thyroidectomy.

Prevention:

  • Taking iodized salt,
  • I / M injection of iodized oil (1-2 ml for an adult).