It is important to understand some of the diseases associated with the Endocrine system.
- Addison’s Disease: caused by hyposecretion of glucocorticoids and aldosterone by the adrenal cortex. Characterised by patches of excessive pigmentation, low blood pressure, weakness, tiredness, and dizziness on standing. It is sometimes thought to be an autoimmune disorder or due to the destruction of the adrenal cortex by cancer or infection.
- Cushing’s Syndrome: caused by the hypersecretion of the corticosteroid hormones by the adrenal cortex. It is characterised by fatigue and excessive fat deposits on the face, torso and back. A person with this syndrome usually has a large round face coupled with thin skin that bruises or tears easily. This can be caused by problems with the adrenal glands or the pituitary gland.
- Diabetes mellitus: caused by an elevation of glucose in the blood (hyperglycaemia). Systems of diabetes, mellitus include increased thirst and urination, weight loss in spite of increased appetite, fatigue, nausea, vomiting, frequent infections and blurred vision. There are two main types of diabetes mellitus:
- Type I diabetes (Insulin dependent diabetes mellitus). This is a most common in people under the age of 20 years and is hereditary, auto immune disorder in which the body’s immune system destroys its own insulin producing cells.
- Type II (acquired diabetes mellitus). This is more common in people who are overweight and do not eat a healthy diet. In this type, insulin levels may be normal, but body cells are resistant or less sensitive to it, therefore the metabolism of carbohydrates fats and protein is altered. Patients with type II may or may not be insulin dependent.
- Calcium deficiency (Hypocalcaemia). Calcium is an essential element in the body, and it is necessary for the formation of bones and teeth and muscular contraction, the normal functioning of many enzymes, blood clotting and normal heart rhythm. Calcium deficiency, hypocalcaemia can be caused by low levels of Parathormones from the parathyroid glands.
- Seasonal affective disorder (SAD): the disorder that usually occurs at the onset of winter and is thought to be caused by the lack of sunlight which leads to an increase in the secretion of melatonin by the pineal gland. SAD is characterised by depression, a lack of interest in one’s usual activities, oversleeping and overeating.
- Acromegaly: Occurs in adults and excessive growth caused by hypersecretion of human growth hormones (HGH). It causes thickening of the bones of the hands, feet, cheeks, and jaw as well as the tissue on the eyelids, lips, tongue, and nose. The skin also thickens, sweat glands enlarge leading to excessive perspiration and other tissues such as heart tissue and nervous tissue can also be affected.
- Diabetes insipidus: is the excessive production of large amounts of very dilute urine. It is characterised by excessive thirst and excessive urination which can quickly lead to dehydration. Diabetes insipidus is caused by lack of antidiuretic hormone which is produced by the pituitary gland.
- Gigantism (Giantism): is excessive growth by hypersecretion of human growth hormone (HGH) in children. Its causes abnormal lengthening of the long bones of the arms and legs so that the individual becomes unusually tall. It is the opposite of dwarfism which can be caused by hypersecretion of HGH in children which is lack of growth.
- Goiter: is an enlarged thyroid gland and it is a symptom of many different thyroid disorders. Often caused by a lack of dietary iodine which is necessary for the correct functioning of the gland.
- Graves disease: is a form of hyperthyroidism. It is a hereditary autoimmune disorder in which the thyroid gland is continually stimulated to produce hormones. Symptoms include an enlarged thyroid gland and oedema behind the eyes which can cause protrusion of the eyeballs.
- Hashimoto’s disease is an auto-immune disease in which the thyroid gland is inflamed, and the secretion of the thyroid hormones is somewhat affected.
- Myxoedema (Hypothyroidism) is the hyposecretion of thyroid hormones if adults. Characterised by a swollen, puffy face due to the oedema of the facial tissues, slow heart rate, low body temperature, sensitivity to cold and dry hair and skin. Also feeling of tiredness and tendency to weight gain.
- Thyrotoxicosis (Hyperthyroidism) is the hypersecretion of thyroid hormones. It can be caused by a tumour, overgrowth of the gland, Grave’s disease, or overstimulation due to an overactive pituitary gland.