Hypothyroidism – How Important Is This Condition?
This is the opposite of hyperthyroidism. In hypothyroidism there is atrophy (wasting) of the thyroid gland and a reduction in its secretion. The condition may be due to a failure of the pituitary gland, in which case it is referred to as secondary hypothyroidism but if it is due to failure of the hypothalamus, it is tertiary.
The condition can be present in childhood, in which case it is referred to as Cretinism; or in adulthood (Myxoedema).
Cretinism
Cretinism is the term used to describe hypothyroidism in children or infants, which is usually caused by a deficiency of the thyroid hormone.
Causes of cretinism
a. Genetic defect: For reasons unknown there is a genetic defect in the formation of the thyroid gland and its ability to secrete enough thyroid hormones needed by the body for its metabolic activities.
b. Goitrous parents: Mothers who suffer from Goitre may not produce enough Thyroid Stimulating Hormone (TSH) needed by the foetus in its formative stage. So when the baby is born it may develop hypothyroidism later in life.
c. Pituitary dysfunction: The pituitary gland controls the activities of the thyroid gland. A dysfunction of the pituitary gland automatically affects the thyroid gland and reduces its development and its ability to secrete thyroid hormone thereby causing cretinism in children.
d. Iodine deficiency: Insufficient or complete deficiency of iodine in the soil and drinking water of a particular place leads to cretinism amongst the children of the area. This is very common in mountainous regions.
Signs and symptoms of cretinism
i. Enlarged tongue
ii. Dull facial expression
iii. Preriorbital oedema
iv. Puffy extremities
v. Thickened skin and lips
vi. Feeding problem
vii. Mental retardation
viii. Growth retardation
ix. Subnormal temperature
x. Coarse features
xi. Squinting
Diagnosis
a. Presenting signs and symptoms can be a clue to diagnosis
b. Radiograph of epiphyses in children or ossification cetres in the wrist or heel in infants will show a delay in bone age compared to the true age of the child.
c. Serum Tyroxine: There is usually a low value of the serum thyroxine concentration when tested.
Myxoedema
Myxoedema is the disorder which occurs in adults as a result of thyroid hormone deficiency. Myxoedema is more common in females who are 45 years and above.
Causes of myxoedema
i. Irradiation: Irradiation which may have been employed in the treatment of goitre can lead to a complete destruction of the thyroid gland and subsequently its inability to secrete thyroid hormones.
ii. Complete thyroidectomy: The surgical removal of the thyroid gland in the treatment of severe goitre or hyperthyroidism leads to thyroid hormone deficiency.
iii. Goitrogens: Consumption of foods high in goitrogen or ingestion of drugs that contain goitrogen can lead to impairment in the function of the thyroid gland.
iv. Autoimmune thyroiditis: For unknown reasons the body develops antibodies which attack the cells of the thyroid gland. This condition which is autoimmune thyroiditis or Hashimoto’s thyroiditis cripples the thyroid gland making it impossible for it to produce thyroid hormone.
v. Anti-tyroid drugs: Over dosage of anti-thyroid drugs lead to hypothyroidism
vi. Prolonged iodine deficiency
vii. Disorder of the hypothalamic-pituitary system.
View the original article here
Return to Losing Weight With Hypothyroidism
Tags: 
