In this article we will discuss about the Goitre:- 1. Meaning of Goitre 2. Clinical Symptoms of Goitre 3. Clinical Effects and Complications 4. Treatment 5. Prevention.
Contents:
- Meaning of Goitre
- Clinical Symptoms of Goitre
- Clinical Effects and Complications of Goitre
- Treatment of Goitre
- Prevention for Goitre
1. Meaning of Goitre:
The term “Goitre” is used to denote enlargement of the thyroid gland of whatever kind. Simple goitre is said to be present when the gland is visible and palpable, but the subject has no symptoms either of hypothyroidism or hyperthyroidism.
Such goitres do not usually affect health, but sometimes they may be complicated with serious consequences. Environmental factors determine the prevalence of most simple goitres—especially dietary factors, of which iodine deficiency is the major one.
2. Clinical Symptoms of Goitre:
The classification of goitre is recommended as:
3. Clinical Effects and Complications of Goitre:
In the majority of cases of simple goitre there are not clinical manifestations due to hypo-function or hyper-function of the thyroid gland. Simple colloid goitre may require surgical treatment because of pressure effects on the adjacent structures.
The following complications occur rarely:
a. Hypothyroidism:
(ii) Hyperthyroidism,
(iii) Cretinism,
(iv) Deaf-mutism.
Such complications are more likely encountered in regions where endemic goitre is prevalent.
4. Treatment of Goitre:
a. A simple goitre in a non-endemic area rarely requires treatment. It happens so that in time it gets smaller without causing any harm. If this does not occur and the goitre becomes disfiguring, iodine therapy is seldom effective, thyroxine 0.2 to 0.3 mg/ day may be given.
This inhibits productions of TSH by the pituitary gland and so reduces the size of the thyroid gland. If there is no response to thyroxine and the goitre continues to be disfiguring, thyroidectomy should be considered, and this is indicated if the size of the goitre leads to obstruction of the trachea.
b. Cretinism may affect up to 5 per cent of the population in places where endemic goitre is severe. There are two types of endemic cretinism. In nervous cretinism there is mental deficiency, deaf mutism, spasticity and ataxia but features of hypothyroidism are rare. In myxoedematous cretinism there is dwarfism, signs of myxoedema and no goitre.
Nervous cretinism can be prevented by giving a single injection of iodized poppy-seed oil to the women of child-bearing age but it must be given before pregnancy starts. It thus appears that iodine is required for the early development of the nervous system before the fetal thyroid appears in the third month of gestation.
In myxoedematous cretins nervous system develops normally in the critical early months but the thyroid gland fails to adapt adequately by hypertrophy to severe iodine deficiency. The thyroid glands are small and uptake of radioiodine very low.
Consequently, such cretins have low plasma T3 and T4 with clinical signs of hypothyroidism, including dwarfism. Both types of cretinism are seen in endemic areas but the proportion of the two varies from region to region.
5. Prevention for Goitre:
a. Iodization of table salt greatly reduces the pre-valance of goitre in many countries. The iodized salt must contain 76 kg of iodine/gm. salt and daily consumption of salt is between 2 and 6 gm. Lower levels of iodization are used in most other countries and are effective. Potassium iodide is used for the iodization of the crude moist salt consumed in many countries.
b. Where goitre is endemic daily intakes of dietary iodine are likely to be less than 50 Hg. This should be increased to the normal range of 100 to 300 µg. The amount of iodine added to the salt should be related to the usual consumption of salt in the community so that individual iodine intakes fall within this range.
Iodine given for medical purposes may cause allergic skin rashes and induce hyperthyroidism, but the risk of these adverse effects from iodized salt is minimal.
c. Iodized oil injections provide an alternative means of prevention in parts of the world where the use of iodized salt is impossible and where endemic goitre is most severe and accompanied by cretinism. Goitres are not merely a cosmetic problem, but impair the vitality of many of the people by causing hypothyroidism, and cretinism retards the intellectual development of children.
A single injection has been found to correct the deficiency for a period of two to three years. Iodized oil has now been used successfully in many countries.
d. Iodization of the water supply in a remote village, where distribution of iodized salt and injection of iodized oil are impractical, reduces the prevalence of goitre. Iodinators consisting of cannisters containing iodine crystals are connected to main water pipes and a fraction of the water diverted through them.