Endocrine Hormones and Disorders

Hyposecretion of Anti-Diuretic Hormone - Diabetes insipidus

Due to decreased production of anti-diuretic hormone in the supraoptic nucleus of the hypothalamus. Often associated with a head injury.

Symptoms:  Excessive diuresis and thirst (polyuria and polydipsia).

Hyposecretion of Growth hormone - Pituitary dwarfism

Due to decreased production of growth hormone from the somatotropic cells of the anterior pituitary.  Generally due to a nonmalignant adenoma of the non-somatotropic tissue of the anterior pituitary.

Symptoms:

1.  hypoglycemia

2.  In Lorain dwarfism:
     a.  arrested sexual
     b.  stunted growth
     c.  normal intelligence
3.  In Frolich's dwarfism:
     a.  arrested sexual
     b.  stunted growth
     c.  mental retardation









Hypersecretion of growth hormone - Giantism and Acromegaly
Pituitary giantism is due to overproduction of growth hormone during childhood.  Usually caused by an adenoma of the somatotropic cells.
Symptoms:  Excessive growth, hyperglycemia, diabetes mellitus, osteoporosis and high basal metabolic rate (BMR).
Acromegaly excessive appositional growth of the skeleton resulting in thickening of the digits and facial features ("lantern jaw" and protruding brow ridges). Increase in height does not occur since at the time of the onset of acromegaly the epiphyseal plates have calcified.  Except for growth in height, symptoms are the same as those for giantism.

Hyposecretion of thymus or absence of gland
DiGeorge syndrome occurs in children born without a thymus gland.  As a result, there is a lack of thymosin production.  Thymosin is needed to stimulate the differentiation of T lymphocytes.
Symptoms:
1.  Little or no immune response.
2.  Inability to resist bacterial, viral or fungal infections.
3.  A lack of cancer cell surveillance.
4.  Inability to reject foreign tissues.






Hyposecretion of thyroid hormone
Myxedema occurs in the adult due to low thyroxine production.  This can be produced by an adenoma of non-thyrotropic cells in the anterior pituitary, low iodine in the diet or autoimmune destruction of the thyroid (Hashimoto's thyroiditis).

Symptoms:
1.  Low BMR and lower body temperature.
2.  Increased fat deposition and lethargy
3.  Low blood pressure, heart rate and respiratory rate
4.  Goiter due to low levels of iodine in blood.
    Cretinism is due to hypothyroidism in infants or children.  In addition to the symptoms seen in myxedema, the patient exhibits stunted growth, mental deficiency and immature sexual development.

Hypersecretion of thyroid hormone
Overproduction of thyroid hormone can be due to adenoma of the thyrotropic cells of the anterior pituitary, a thyroid tumor or an autoimmune reaction to TSH receptors on thyrotropic cells (Graves' disease).
Symptoms:
1.  High BMR & body temperature with profuse sweating.
2.  Increased appetite with weight loss.
3.  Increased heart rate, blood pressure and respiratory rate.
4.  Muscular tremor and nervousness
5.  Cardiac arrhythmias.
6.  Toxic goiter and exophthalmia (Graves' disease).

Hypersecretion of parathyroid hormone
An excess of parathyroid hormone production is due to a tumor of the parathyroid gland.

Symptoms:
1.  High blood calcium.
2.  Decalcification of bone which leads to fractures
3.  Cardiac arrhythmias.
4.  Tetany in skeletal muscles.



Hyposecretion of parathyroid hormone
The non-function of the parathyroid glands produces below normal levels of calcium in the blood.
Symptoms:
1.  Spontaneous nerve depolarization cause convulsions.
2.  Cuffing the arm leads to irreversible flexion of fingers.

Hyposecretion of insulin - Diabetes mellitus
Due to a lack of insulin from nonfunctioning beta cells of the pancreatic islets.  There are two primary forms of this disease:
1.  Type I or juvenile onset diabetes mellitus generally occurs in people younger than 20 years (insulin dependent diabetes).  This is the consequence of an autoimmune destruction of islet beta cells.
2.  Type II or late onset diabetes mellitus usually occurs in people who are over the age of 40 and overweight.  In many cases, diet and exercise can reverse symptoms.

Symptoms: 
1.  Hyperglycemia
2.  Polyuria, polydipsia and polyphagia.
3.  Ketoacidosis which can lead to diabetic coma and death.

Hypersecretion of insulin - hyperinsulinism
A tumor of the islet beta cells will cause an overproduction of insulin.  This will produce a pronounced hypoglycemia.  There is a very low incidence of this condition.
Symptoms:
1.  Anxiety and sweating.
2.  Body tremors
3.  Elevated body temperature
4.  Disorientation
4.  The patient can go into Insulin shock due to brain hypoglycemia. 









Hyposecretion of glucagon - chronic hypoglycemia

A decreased ability to secrete glucagon from pancreatic alpha cells has been associated with chronic hypoglycemia.  

Other contributing factors to this condition would be:
1.  A beta cell tumor
2.  Defect in the mechanism releasing glucose from the liver.
3.  Addison's disease - low levels of corticosteroids which enhance glucose production.
4.  Hyposecretion of growth hormone 

Hyposecretion of adrenal steroids - Addison's disease
This is an uncommon disease since both adrenal glands must suffer a 90% loss of function before symptoms appear.  In 25% of the cases, degeneration of the adrenal cortex is due to chronic TB.  Autoimmune destruction of the cortical tissue is believed to be another cause.

Symptoms:
1.  Hypoglycemia, hyponatremia and hyperkalemia
2.  Severe dehydration leads to hypovolemia.
3.  Gastrointestinal disorders
4.  Low tolerance to stress or trauma
5.  Hyperpigmentation due to elevated levels of ACTH in blood.

Hypersecretion of adrenal steroids - Cushing's syndrome
Chief causes of Cushing's syndrome:
1.  Hypersecretion of ACTH - Pituitary Cushing's syndrome is responsible for 60 to 70% of these cases.  This condition is brought on by a pituitary adenoma.2.  Hypersecretion of adrenal steroids due to an adenoma of the adrenal cortex (20% of the cases) produces low levels of ACTH by negative feedback.  This is called adrenal Cushing's syndrome.
3.  Hypersecretion of ACTH by a non-endocrine cancer, e.g., lung carcinoma.  This is called paraneoplastic Cushing's syndrome and is responsible for 10 to 15% of the cases.
4.  Iatrogenic Cushing's syndrome is due to the long term use of glucocorticoids to control inflammation and edema or autoimmune diseases like rheumatoid arthritis.

Symptoms:
1.  Hyperglycemia due to enhanced gluconeogenesis.
2.  Easy bruising and muscular weakness.
3.  Decreased immunity.
4.  Hypernatremia leading to excessive water retention.
5.  Hyperkalcemia and high blood pressure.
6.  Shifting "moon face" and "Buffalo hump".
7.  In a male child - Muscular hypertrophy
8.  In a female child or adult - Virilsm (bearded lady).

Source: 
http://faculty.ucc.edu/biology-potter/Endocrine%20hormones%20and%20disorders.htm