What is iodine deficiency goiter?

It occurs due to a lack of iodine in the diet, in vegetables and/or in the water. It is common among the people living in the hills, where the iodine content of the soil is limited, due perhaps to soil erosion by continued rains, etc. It is thus endemic, i.e. at such a place, one can find several people with swollen necks, as a result of an enlarged thyroid gland. More precisely, the disease is called endemic iodine deficiency goiter.

Hence, when the food/water taken by persons in such areas is deficient of iodine, the supply of iodine to the thyroid gland suffers, and there is a constant pressure on the gland to secrete normal amount of hormones. As a result, the gland goes on increasing in size, and even its shape may get distorted, and it may become nodular, the so-called multinodular goitre. In its initial stages, there may be only a smooth enlargement of both the lobes of the thyroid gland, as in puberty goiter.

Hence it may be said that the thyroid gland is very loyal to the body, so that even if there is a constant inadequate supply of iodine to the gland, it goes on supplying/manufacturing/ producing sufficient amount of hormones for the normal activity of the body, although the gland itself increases in size enormously.

One may think that if the thyroid gland is enlarged, there should be a corresponding increase in the production of thyroid hormones. But that is not always so, although in some of the cases, the gland may turn toxic or hyperactive, or underactive, and yet in some other cases, malignancy may develop, as in cases of multinodular goiter. Hence the size of the thyroid gland may not indicate the true pathology developing in the gland.

Practical approach / hints for investigating a case of goiter and/or solitary nodule/s:

In any case of goiter and/ or solitary nodule / s in the thyroid gland, one needs to look for the following:

(i) Is it malignant?

(ii) Is any treatment required?

(iii) Has it caused hyperactivity or underactivity of the thyroid functions?

All the above points have been explained further, and they are necessary so that nothing remains undetected, and the specific treatment is not delayed.

Although an enlarged thyroid gland (goiter) may not disturb the functioning of the body, yet due to its enlarged weight/ size, it may press the underlying trachea (windpipe) or oesophagus (food-pipe), so that the patient may have some difficulty in breathing as well as in swallowing. Cosmetic factors, especially in females, should also be considered. Thus, a portion of the thyroid gland may have to be removed surgically in selected cases.

Prophylaxis for endemic iodine deficiency goiter:

As a prophylactic measure, in endemic areas, for all normal persons/ children, iodized salts should be used as a matter routine.

Other causes of goiter

An enlargement of the thyroid gland may also occur in persons who are addicted to heavy smoking, and those who are taking PAS (paraaminosalicylic acid) for the treatment of tuberculosis.