Common Endocrine Disorders

A disorder of any endocrine gland can greatly affect other endocrine glands as well as many major body systems.


Pituitary Gland Disorders

Disorders of the pituitary gland often result from either an over-production or under-production and secretion of a hormone.

Acromegaly

OVERVIEW
WHAT IS TESTED?

Acromegaly results from an over-secretion of growth hormone (GH) during childhood. Over secretion results from an increased number of cells, which most often is caused by a benign tumor, called an adenoma. When the pituitary gland does not respond to hypothalamic inhibiting hormones, bone and tissue growth is stimulated by insulin-like growth factor (IGF), a hormone released by the liver. Un-tested GH allows production of IGF to continue, leading to widening and lengthening of bones, organ enlargement, increased blood glucose levels, and high levels of fat in the blood.

• Blood glucose
• GH
• IGF

Diabetes Insipidus

OVERVIEW
WHAT IS TESTED?

Diabetes insipidus is characterized by the excretion of large volumes of urine. This disorder can result from insufficient ADH from the pituitary gland or when the kidneys fail to respond to the hormone.

• Urine volume
• Urine specific gravity
• Serum osmolality

Syndrome of Inappropriate Antidiuretic Hormone Secretion

OVERVIEW
WHAT IS TESTED?

Syndrome of inappropriate antidiuretic hormone secretion is caused by a continued release of ADH, leading to an increase in fluid volume, water retention and muscle cramps. The increase in fluid volume will eventually dilute the blood stream, causing an decrease in normal sodium level.

• Serum sodium
• Serum osmolarity
• Urine sodium
• Urine osmolarity

Thyroid Gland Disorders

Thyroid disorders can be difficult to detect because early symptoms are usually vague. Long-term treatment and periodic follow-up examinations may be needed to monitor response.

Hyperthyroidism

OVERVIEW
WHAT IS TESTED?

Hyperthyroidism, or Graves disease is caused by a hyper secretion of thyroid hormones possibly resulting from stress, infection, pituitary tumors or thyroid tumors. The disease itself eventually causes an increased metabolic rate, rapid heart beat, anxiety, heat intolerance and irregular menstruation.

• Protein-bound iodine
• Free T3 (FT3)
• Free T4 (FT4)
• Thyroglobulin
• Serum T3 and T4
• TSH

Thyrotoxic Crisis (Thyroid Storm)

OVERVIEW
WHAT IS TESTED?

Thyrotoxic crisis is a rare but life-threatening variation of hyperthyroidism. The condition is thought to be triggered by infection, extreme stress, diabetic ketoacidosis, thyroid gland manipulation, or presence of toxins in the blood during pregnancy.

• Serum T3
• Serum T4

Hypothyroidism

OVERVIEW
WHAT IS TESTED?

Hypothyroidism results from an inadequate secretion of thyroid hormones. The condition may originate in the thyroid or be caused by an insufficient secretion of TSH in the pituitary. Both causes produce a slowing of all metabolic processes, fatigue, cold intolerance and forgetfulness.

• TSH
• FT3
• FT4
• T3
• T4

Thyroiditis

OVERVIEW
WHAT IS TESTED?

Thyroiditis is the term to describe inflammation of the thyroid gland. Although there are many different causes and types of thyroiditis, all involve the release of higher than normal levels of hormone and changes in thyroid activity from over-activity to under-activity. Inflammation causes the gland to enlarge and sometimes tender. Hashimoto’s thyroiditis is the most common type of thyroiditis and is believed to be an autoimmune disorder.

• CBC (Specifically, WBC count)
• Thyroid function tests
• Antimicrosomal antibodies
• Antithyroglobulin antibodies

Parathyroid Gland Disorders

Dysfunction of the parathyroid gland occurs as a result of over or under-secretion of parathyroid hormone (parathormone) and affects vital minerals needed to remain healthy.

Hyperparathyroidism

OVERVIEW
WHAT IS TESTED?

Hyperparathyroidism is most commonly caused by an adenoma, a benign tumor of one of the parathyroid glands. It can develop from an excessive secretion of parathyroid hormone (parathormone), resulting in increased elimination of phosphorous in urine or from an increase in parathormone secretion in response to low blood calcium levels. The latter may result from vitamin D deficiency, chronic kidney failure, large doses of some diuretics and excessive use of laxatives and calcium supplements.

• Serum calcium
• Serum phosphorous
• 24-hour urine test
• Parathormone measurement

Hypoparathyroidism

OVERVIEW
WHAT IS TESTED?

Hypoparathyroidism occurs from a deficiency in parathormone that results in low blood calcium. Calcium levels are regulated and balanced by parathormone by increasing calcium absorption in the GI tract. Low blood calcium can result in muscle spasms and abnormal skin sensations. The most common causes of hypoparathyroidism include trauma to the parathyroid glands and thyroidectomy, the complete removal of the thyroid gland.

• Serum calcium level
• Serum phosphorous level
• Urine calcium
• Urine phosphorous

Adrenal Gland Disorders

Adrenal gland dysfunction can include disease of the outer cortex, which synthesizes and secretes corticosteroids, mineralocorticoids, glucocorticoids and androgens; or the inner medulla, which secretes epinephrine and norepinephrine. Proper secretion of adrenal hormones is essential to life.

Addison’s Disease

OVERVIEW
WHAT IS TESTED?

Addison’s disease is a type of adrenal insufficiency that results from destruction of the adrenal cortex by other diseases such as tuberculosis. It may also be classified as an autoimmune disorder, in which antibodies formed by the immune system destroy adrenal tissue. Consequences of reduced adrenal function include decreased glucose reserves and low blood sugar. Addison’s disease may also result occur as the result of surgical removal of both adrenal glands.

• Serum cortisol levels
• Serum sodium
• Fasting blood glucose
• Serum potassium
• Serum calcium
• Blood urea nitrogen (BUN)

Pheochromocytoma

OVERVIEW
WHAT IS TESTED?

Pheochromocytoma results from a benign tumor of the adrenal medulla. Hyper function causes the adrenal medulla to secrete excessive epinephrine and norepinephrine. Episodic symptoms can be triggered by exercise, emotional distress, surgery, tumor manipulation or postural changes. Individuals who should be tested for pheochromocytoma include those who (1) have high blood pressure that is difficult to control; (2) take more than four medications to control blood pressure, or (3) develop high blood pressure before 35 years of age.

• 24-hour urine
• Urinary catecholamine

Cushing’s Syndrome

OVERVIEW
WHAT IS TESTED?

Cushing’s syndrome results from excessive secretion of hormones by the adrenal cortex. An overproduction of hormones can result from (1) overproduction of ACTH by the pituitary gland; (2) excessive production and secretion of glucocorticoids, mineralcorticoids and gonadocorticoids; (3) benign or malignant tumors of the pituitary gland or adrenal cortex; or (4) prolonged usage of high doses of corticosteroids.

• 17-OHCS
• 17-KS
• Plasma cortisol
• Urine cortisol
• Plasma ACTH
• Serum sodium
• Serum potassium
• Blood glucose

Hyperaldosteronism

OVERVIEW
WHAT IS TESTED?

Hyperaldosteronism is caused by the hyper secretion of aldosterone, leading to extreme electrolyte imbalances. Aldosterone is a mineralocorticoid and is regulated by serum levels of sodium and potassium, ACTH and the renin-angiotensin system; a process occurring in the kidneys. Excessive secretion of aldosterone results in increased sodium and water retention and increased potassium excretion in urine.

• Serum potassium
• Serum sodium
• Serum bicarbonate
• Serum aldosterone
• Plasma renin