Hypothyroidism | Myxedema | cretinism | hashimoto's thyroiditis

Hypothyroidism-
Decreased secretion of thyroid hormone is called hypothyroidism.

Hypothyroidism leads to myxedema in adults and cretinism in children.

Myxedema-
Myxedema is the hypothyroidism in adults.
It is characterized by generalised edematous appearance.

Causes of myxedema-

Myxedema is caused by deficiency of thyroid stimulating hormone (TSH) or thyrotropin releasing hormone.
It occurs due to disease of thyroid gland, genetic disorder or iodine deficiency.

common cause of myxedema is the autoimmune disease that is called hashimoto's thyroiditis which is common in late middle aged women.

in most of patients it starts with glandular inflammation called thyroiditis caused by autoimmune antibodies.
Later it leads to destruction of the glands.

Signs and symptoms of myxedema-

typical feature of this disorder is an edematous appearance throughout the body.
It is associated with the following symptoms-
1. Bagginess under the eyes.
2. Swelling of the face.
3. Non pitting type of edema.
It means when pressed it does not make bits and the idiom is hard.
it is because of accumulation of proteins with hyaluronic acid and chondroitin sulfate which form a hard tissue with increased accumulation of fluid.
4. Atherosclerosis-
it is the hardening of the walls of arteries because of accumulation of fat deposits and other substances.

in myxoedema, it occurs because of increased plasma level of cholesterol which leads to deposition of cholesterol on the walls of the arteries.

atherosclerosis produces arteriosclerosis which refers to thickening and stiffening of arterial wall.
Arteriosclerosis causes hypertension.

General features of hypothyroidism in adults-

1. Anaemia
2. Cold intolerance
3. Frog like Husky voice
4. Depressed hair growth
5. Constipation
6. Increased in body weight
Mostly Central obesity
7. Mental sluggishness
8. Scaliess of the skin
9. Fatigue and muscular sluggishness
10. Extreme Somnolence (excess slipingness) with sleeping upto 14 to 16 hours per day.
11. Menorrhagia
12. Polymenorrhea
13. decrease cardiovascular function such as reduction in rate and force of contraction of the heart , cardiac output and blood volume.

CRETINISM-
Hypothyroidism in childrens.
It is characterized by stunted (retarted) growth.

Causes of cretinism-
cretinism occurs due to
- congenital absence of thyroid gland
- genetic disorder or
- lack of iodine in the diet.

Features of cretinism-

A. newborn baby with thyroid deficiency appear normal at the time of birth because thyroxine might have been supplied from Mother.

but a few weeks after birth the baby started developing the science like sledges movement and croaking sound while crying.

Unless stated immediately the baby will be mentally retarded permanently.

B . Skeletal growth is more effective than the soft tissues so there is stunted growth with bloated body.

The tongue becomes so big (macroglossia) that it hangs down with dripping of saliva.

The big tongue of struct swelling and breathing.
the tongue produces characteristic guttural breathing that may sometimes Choke the baby.

Cretin vs dwarf-

A cretin is different from pituitary Dwarf.

in cretinism there is mental retardation and the different parts of the body are disproportionate.

In dwarfism, the development of nervous system is normal and the parts of the body are proportionate.

the reproductive system is affected in cretinism but it may be normal in dwarfism.