1. Chapter Fifteen Endocrine System
Mastering Healthcare Terminology/Chapter 15

2. Quote “If I’d known I was gonna live this long, I’d have
taken better care of myself.”
– Eubie Blake at age 100
Would you like to be: old and healthy or old and ill?
Mastering Healthcare Terminology/Chapter 15

3. Function and Specialty/Specialist
Endocrinology
Specialist
Endocrinologist
Function
Hormones/chemical messengers
Explain the concept of hormones as chemical messengers that travel through the circulatory system to assist in regulating body functions.
The study of the glands that secrete hormones within the body is endocrinology; the medical doctor who diagnoses and treats disease and disorders of the endocrine system is an endocrinologist.
Mastering Healthcare Terminology/Chapter 15

4. Anatomy and Physiology
Endocrine (crin/o) glands
Target cells and receptor sites
The endocrine (endo- within + -crine = to secrete) glands secrete hormones that act on specific cells called “target cells” at specific sites termed “receptor sites.” The hormones and their target cells are similar to a lock and key: both are necessary for the hormones to effect their action.
Endocrine glands
Mastering Healthcare Terminology/Chapter 15

5. Pituitary Gland/Hypophysis
Location
“Master gland”
Anterior lobe/ adenohypophysis (aden/o, hypophys/o)
Posterior lobe/ neurohypophysis (neur/o, hypophys/o)
The pituitary gland (also called the hypophysis) is a tiny gland located behind the optic nerve in the cranial cavity.
It is also known as the “master gland” because of its role in controlling other endocrine glands. The name hypophysis is the proper anatomic term.
Divided into two lobes, the anterior lobe, called the adenophypophyis, is composed of glandular tissue (aden/o) and secretes hormones in response to stimulation by the hypothalamus. The principal hormones and the target organs on which they act are growth hormone/the bones; adrenocorticotropic hormone/the adrenal cortex; thyroid-stimulating hormone/thyroid; gonadotropic hormones/ovaries and testes; and prolactin/mammary glands.
Be careful! Do no confuse aden/o, which means gland, with adren/o, which means the adrenal gland.
The posterior lobe, the neurohypophysis, is composed of nervous tissue (neur/o) and secretes hormones that it receives from the hypothalamus. The two hormones released by this lobe are antidiuretic hormone (ADH), which acts on the tubules of the kidneys, and oxytocin (OT), which acts on the uterine smooth muscle and the mammary glands.
Be careful! Do not confuse oxytocin with oxytocia, which means a rapid birth.
Pituitary hormones
Mastering Healthcare Terminology/Chapter 15

6. Thyroid Gland (thyroid/o)
Location
Regulation of metabolism
Tetraiodothyronine (thyroxine)
Triiodothyronine
Control of calcium deposited in bones
Calcitonin
The thyroid gland is a single organ that is located in the anterior part of the neck. It is responsible for metabolism and normal growth and development. It also controls the amount of calcium that is deposited in the bones. The hormones secreted are: Calcitonin, which regulates the amount of calcium in the bloodstream;Tetraiodothyronine (thyroxine), which increases cell metabolism; Triiodothyronine, which increases cell metabolism.
Thyroid gland
From Thibodeau and Patton: Anatomy and physiology, ed 6, Mosby
Mastering Healthcare Terminology/Chapter 15

7. Parathyroid Glands (parathyroid/o)
Location
Regulate calcium (calc/o) in the bloodstream
The parathyroids are four small glands that are located on the posterior surface of the thyroid gland in the neck. They secrete parathyroid hormone (PTH) in response to a low level of calcium in the blood. If a low level of calcium is detected, PTH increases the level by causing it to be released from the bones. This results in calcium reabsorption by the kidneys and the digestive system. PTH is inhibited by high levels of calcium.
Parathyroid glands
From Thibodeau and Patton: Anatomy and physiology, ed 6, Mosby
Mastering Healthcare Terminology/Chapter 15

8. Clicker Question Hypophys/o is a combining form for the:
A. adrenal cortex
B. adrenal medulla
C. pineal gland
D. pituitary gland
D. pituitary gland
Mastering Healthcare Terminology/Chapter 15

9. Adrenal Glands/Suprarenals (adren/o)
Location
Adrenal cortex
Secretes steroids
Adrenal medulla
Sympathomimetic hormones
The adrenal glands (also called the suprarenals) are paired glands that are located on top of each kidney (ad- = toward + ren/o = kidney). They are composed of an outer part, called the adrenal cortex, and an inner part, called the adrenal medulla.
The adrenal cortex secretes three hormones that are steroids.
The adrenal medulla secretes sympathomimetic hormones that stimulate the fight-or-flight response to stress, similar to the sympathetic nervous system.
Mastering Healthcare Terminology/Chapter 15

10. Pancreas (pancreat/o)
Location
Exocrine function
Release digestive enzymes
Endocrine function
Regulate glucose in the blood
The pancreas is located inferior (below) and posterior (behind) to the stomach. It functions as an exocrine gland to release digestive enzymes through a small duct into the small intestines.
Its endocrine function, through a variety of cells in the islets of Langerhans, is to regulate the level of glucose in the blood by stimulating the liver.
The alpha cells produce the hormone glucagon, which increases the level of glucose in the blood when levels are low.
The beta cells produce insulin, which decreases the level of glucose in the blood when levels are high.
In the absence of glucose in the cells, proteins and fats are broken down, causing excessive fatty acids and ketones (waste products from the breakdown of fat) in the blood.
Mastering Healthcare Terminology/Chapter 15

11. Thymus Gland (thym/o) Location Stimulation of cells
for immune response
The thymus gland is located in the mediastinum above the heart. It releases the hormone thymosin, which is responsible for stimulating key cells in the immune response.
Be careful! Do not confuse thyr/o, which means thyroid, and thym/o, which means thymus.
Thymus gland
From Drake: Gray’s anatomy for students, Churchill-Livingstone
Mastering Healthcare Terminology/Chapter 15

12. Ovaries and Testes Locations Reproductive functions
The ovaries and testes, the female and male gonads, act as endocrine glands to influence reproductive function. The ovaries are located in the pelvic cavity of the female and the testes in the scrotum of the male. These will be discussed in more detail in each chapter on their individual disorders.
Mastering Healthcare Terminology/Chapter 15

13. Pineal Gland Location Secretion of melatonin
The pineal gland is located in the center of the brain, functioning to secrete the hormone melatonin, which is thought to be responsible for inducing sleep.
Mastering Healthcare Terminology/Chapter 15

14. Clicker Question
The gland that regulates metabolism and normal growth and development of the body is the:
A. adrenal cortex
B. pituitary
C. thymus
D. thyroid
D. thyroid
Mastering Healthcare Terminology/Chapter 15

15. Terms Related to Signs and Symptoms of Endocrine Disorders
Anorexia
Exophthalmia
Goiter
Goiter
Anorexia (an- = without + orex/o = appetite) is a lack of appetite. Don’t confuse this with anorexia nervosa, which is an eating disorder.
Exophthalmia (ex- = out + ophthalm/o = eye) is a protrusion of the eyeballs from their orbits.
Goiter is an enlargement of the thyroid gland that is not due to a tumor.
Anorexia
Exophalmia
From Thibodeau: Anatomy and physiology, ed 6, Mosby
Mastering Healthcare Terminology/Chapter 15

16. Terms Related to Signs and Symptoms of Endocrine Disorders (cont’d)
Hirsutism
Paresthesia
Tetany
Hirsutism is abnormal hairiness, especially in women. It is also called hypertrichosis (hyper- = excessive + trich/o = hair + -osis = abnormal condition).
Paresthesia (par- = abnormal + esthesi/o = feeling) is an abnormal sensation such as prickling.
Tetany is continuous muscle spasms.
Hirsutism
Tetany
Mosby’s medical dictionary, ed 7, Mosby
Mastering Healthcare Terminology/Chapter 15

17. Terms Related to Signs and Symptoms of Endocrine Disorders (cont’d)
Glucosuria
Ketoacidosis
Ketonuria
Polydipsia
Polyphagia
Polyuria
Glucosuria is the presence of sugar (glucose) in the urine. This may indicate diabetes mellitus and is sometimes referred to as glycosuria.
Ketoacidosis is the excessive amount of ketone acids in the bloodstream.
Ketonuria is the presence of ketones in the urine.
Polydipsia is a condition of excessive thirst (dips/o = thirst). Note that poly- does not translate well as “many” when the term has to do with thirst, eating, or urination. The meaning “excessive” is suggested in these contexts instead.
Polyphagia (phag/o = to eat, swallow) is a condition of excessive appetite.
Polyuria is a condition of excessive urination.
Mastering Healthcare Terminology/Chapter 15

18. Terms Related to Signs and Symptoms of Endocrine Disorders (cont’d)
Hypocalcemia – Hypercalcemia
Hypoglycemia – Hyperglycemia
Hypokalemia – Hyperkalemia
Hyponatremia – Hypernatremia
Hypo- in each of the following terms indicates a deficiency, while the prefix hyper- refers to an excessive amount. Note that each of these is also a blood condition (-emia = blood condition).
Calc/o = calcium.
Glyc/o = glucose.
Kal/i= potassium.
Natr/o = sodium.
Decode the terms and note that the chemical symbols for calcium (Ca), potassium (K), and sodium (Na) can help students remember these combining forms.
Mastering Healthcare Terminology/Chapter 15

19. Clicker Question A condition of excessive potassium in the blood is:
A. hypercalcemia
B. hyperkalemia
C. hypocalcemia
D. hypokalemia
hyperkalemia
Hyper- = excessive + Kal/i = potassium
Mastering Healthcare Terminology/Chapter 15

20. Terms Related to Pituitary Gland Disorders
Acromegaly
Gigantism
Growth hormone deficiency (GHD)
Each of these disorders is characterized by too much or too little growth hormone (somatotropin).
Acromegaly (acro- = extremities + -megaly = enlargement) is an enlargement of the extremities (the hands and feet) along with the jaw, nose, and forehead. This is caused by an oversecretion of somatotropin during the adult years. The cause of the oversecretion is usually a benign glandular tumor (adenoma) of the pituitary gland.
Gigantism is a hypersecretion of somatotropin during childhood, leading to an excessive amount of growth.
Growth hormone deficiency (GHD) is an undersecretion of somatotropin due to a dysfunction of the pituitary. This disorder leads to dwarfism. If the deficiency is acquired during adulthood, the patient develops obesity, weakness, and cardiac difficulties.
GHD
Acromegaly
From Zitelli: Atlas of pediatric physical diagnosis, ed 5, Mosby
From Ignatiavicious: Medical-surgical nursing,
ed 5, Saunders
Mastering Healthcare Terminology/Chapter 15

21. Terms Related to Pituitary Gland Disorders (cont’d)
Diabetes insipidus
Syndrome of inappropriate antidiuretic hormone (SIADH)
Panhypopituitarism
Diabetes insipidus (DI) is an undersecretion of antidiuretic hormone (ADH) from the neurohypophysis that results in symptoms of polydipsia and polyuria. It may be treated with vasopressin.
The syndrome of inappropriate antidiuretic hormone (SIADH) is the opposite of diabetes insipidus. In this disorder, there is an oversecretion of antidiuretic hormone that leads to severe hyponatremia and the inability to excrete diluted urine.
Panhypopituitarism (pan- = all) is a difficiency of all pituitary hormones leading to weight loss, weakness, hypotension, and loss of libido (normal psychological drive for sensuality). This is also known as Simmonds disease.
Mastering Healthcare Terminology/Chapter 15

22. Clicker Question
Which of the following terms is an enlargement of the extremities due to hypersecretion of somatotropin?
A. gigantism
B. SIADH
C. acromegaly
D. GHD
C. acromegaly
Mastering Healthcare Terminology/Chapter 15

23. Terms Related to Thyroid Disorders
Hyperthyroidism
Thyrotoxicosis
Graves disease
Hypothyroidism
Cretinism (childhood)
Myxedema (adults)
Hyperthyroidism (also called thyrotoxicosis) is excessive thyroid hormone production. The most common form is Graves disease, which may be accompanied by exophthalmia and ketonuria.
Hypothyroidism is deficient thyroid hormone production. If it occurs during childhood, it may cause a condition called cretinism, which results in stunted mental and physical growth. The extreme form of hypothyroidism in adults is termed myxedema, which is characterized by facial and orbital edema.
Mastering Healthcare Terminology/Chapter 15

24. Terms Related to Parathyroid Disorders
Hyperparathyroidism
Hypoparathyroidism
Hyperparathyroidism is an overproduction of parathyroid hormone. Symptoms include polyuria, hypercalcemia, hypertension, and kidney stones.
Hypoparathyroidism is a deficient amount of parathyroid hormone production resulting in tetany, hypocalcemia, irritability, and muscle cramps.
Mastering Healthcare Terminology/Chapter 15

25. Terms Related to Adrenal Gland Disorders
Addison disease
Cushing disease
Cushing disease
Before
treatment
Addison disease is an insufficient secretion of adrenal cortisol from the adrenal cortex. Symptoms include gastric complaints, hypotension, and dehydration.
Cushing disease is an excessive secretion of cortisol by the adrenal cortex. Symptoms include obesity, leukocytosis (a slight increase of white blood cells), hirsutism (abnormal hairiness), hyperglycemia, and muscle wasting. The illustration shows the boy before treatment and then four months after treatment was started.
After
treatment
From Damjanov: Anderson’s pathology, ed 10, Msoby
Mastering Healthcare Terminology/Chapter 15

26. Terms Related to Pancreas Disorders
Diabetes mellitus
Gestational diabetes
Hyperinsulinism
Prediabetes
Type I diabetes
Type 2 diabetes
Diabetes mellitus is a group of metabolic disorders characterized by high glucose levels that result from inadequate/ineffective amounts of insulin.
Gestational diabetes (gestation= pregnancy) is insulin resistance by the mother acquired during pregnancy. Although it usually resolves at birth, some of these women are more likely to develop type 2 diabetes later in life.
Hyperinsulinism is an excessive amount of insulin that is seen in some infants at birth. It causes severe hypoglycemia.
Prediabetes is a condition of an elevated blood glucose level, but not high enough for a diagnosis of type 2 diabetes.
Type 1 diabetes is a total lack of insulin production. It results in glycosuria, polydipsia, polyphagia, polyuria, blurred vision, fatigue, and frequent infections. It is currently thought to be an autoimmune disorder. A previous name for type 1 diabetes is insulin-dependent diabetes mellitus (IDDM).
Type 2 diabetes is a deficient amount of insulin production, with symptoms similar to type 1 diabetes. The causes are unknown, but obesity and family history are closely associated with the incidence of the disease. Type 2 diabetes was formerly termed non-insulin-dependent diabetes mellitus (NIDDM).
Mastering Healthcare Terminology/Chapter 15

27. Terms Related to Benign Neoplasms
Pheochromocytoma
Prolactinoma (pituitary tumor)
Thymoma
Prolactinoma
A pheochromocytoma (phe/o = dark + chrom/o + color + cyt/o = cell + -oma = tumor) is usually a benign tumor of the adrenal medulla. The name was acquired because of the dark appearance of the cells compared to their normal appearance.
A prolactinoma is the most common type of pituitary tumor. It causes the pituitary to oversecrete prolactin, the hormone that stimulates milk production in the breast.
A thymoma is a noncancerous growth of epithelial origin that is often associated with myasthenia gravis.
Thymoma
Mastering Healthcare Terminology/Chapter 15

28. Terms Related to Malignant Neoplasms
Islet cell carcinoma (pancreatic Cancer)
Malignant thymoma (rare cancer of thymus gland)
Thyroid carcinoma (5yr survival rate)
Islet cell carcinoma is the medical term for pancreatic cancer. It is the fourth leading cause of cancer death in the United States. The most common treatment is a Whipple procedure, a pancreatoduodenectomy. Decode pancreatoduodenectomy.
A malignant thymoma is a rare cancer of the thymus gland.
Thyroid carcinoma (thyroid cancer) is most commonly seen in either its follicular or papillary forms. Both of these have high 5-year survival rates.
Whipple Procedure
Mastering Healthcare Terminology/Chapter 15

29. Clicker Question A prolactinoma is a tumor of which gland?
A. pituitary
B. pancreas
C. thyroid
D. thymus
A. pituitary
Mastering Healthcare Terminology/Chapter 15

30. Age Matters Pediatrics Geriatrics Growth hormone deficiency Gigantism
Type 1 diabetes
Geriatrics
Type 2 diabetes
Discuss the most commonly occurring pediatric and endocrine disorders.
Mastering Healthcare Terminology/Chapter 15

31. Terms Related to Laboratory Tests
A1c
Fasting plasma glucose (FPG)
Glucometer
Oral glucose tolerance test (OGTT)
Urine glucose
Urine ketones
Each of the diagnostic terms on this slide are used to detect/monitor diabetes mellitus.
The A1c (also called glycosylated hemoglobin or HbA1c) is a measure of the average blood glucose during a 3-month time span. It is used to monitor diabetes treatment.
A fasting plasma glucose (formerly called a fasting blood sugar) is a blood test that is done to measure the amount of glucose present in the blood. It measures the body’s ability to break down and use glucose. If the measure is between 100 and 125 mg/dL it indicates a prediabetic state; if it is over 126 mg/dL it indicates a diagnosis of diabetes.
A glucometer (gluc/o = sugar + -meter = instrument to measure) is an instrument to measure blood sugar.
An oral glucose tolerance test is a blood test to measure the body’s response to a concentrated glucose solution. It is used to diagnose diabetes mellitus.
A urine glucose test is used to screen for or to monitor diabetes mellitus. A urine specimen is examined for the presence of glucose.
If a urine specimen is positive for urine ketones, their presence may indicate diabetes mellitus or hyperthyroidism.
Mastering Healthcare Terminology/Chapter 15

32. Terms Related to Laboratory Tests (cont’d)
Hormone tests
Radioimmunoassay studies (RIA)
Thyroid function tests (TFTs)
Total calcium
Urinalysis
Hormone tests examine the quantity of various hormones in the blood to diagnose or monitor a disease. Examples are antidiuretic hormone, cortisol, growth hormone, or parathyroid hormone.
Radioimmunoassay studies are nuclear medicine tests to tag and detect hormones in the blood through the use of radionuclides.
Thyroid function tests are blood tests done to assess triiodothyronine, tetraiodothyronine (thyroxine), and calcitonin. They may be used to assess abnormalities of thyroid function.
Total calcium is a measure of the amount of calcium in the blood. Results may be used to assess parathyroid function, calcium metabolism, or cancerous conditions.
Urinalysis is a physical, chemical, and microscopic examination of the urine. Urine glucose and urine ketones are two substances that may be present to indicate difficulties with pancreatic function.
Mastering Healthcare Terminology/Chapter 15

33. Terms Related to Imaging
Computed tomography (CT) scan
Magnetic resonance imaging (MRI)
Radioactive iodine (RAI) uptake scan
Radiography
Sonography
Computed tomography may be used to test for bone density in hypoparathyroidism or for the size of the adrenal glands in Addison disease.
Magnetic resonance imaging may be used to examine changes in the size of soft tissue, for example, the pituitary, pancreas, or hypothalamus.
Radioactive iodine (RAI) uptake scans are done to test thyroid function by measuring the gland’s ability to concentrate and retain iodine. It is useful in diagnosing hyperthyroidism.
Radiography (x-rays) is used to examine suspected changes that affect the density or thickness of bone. It may also be used to reveal underlying causes of an endocrine disorder.
Sonography is used to visualize the pancreas and to guide biopsies of the thyroid gland when determining if cysts are solid or fluid filled.
Sonography of abdomen
From Hagen: Diagnostic ultrasonography, ed 5, Mosby
Mastering Healthcare Terminology/Chapter 15

34. Terms Related to Excisions
Adrenalectomy
Hypophysectomy
Pancreatectomy
Parathyroidectomy
Thyroidectomy
Aside from medications, resections of endocrine glands are the most common interventions.
An adrenalectomy is a bilateral removal of the adrenal glands to reduce excess hormone secretion.
A hypophysectomy (hypophys/o = pituitary) is a removal of the pituitary gland. This is normally done to remove a pituitary tumor.
A pancreatectomy is a removal of part or all of the pancreas. Usually this is done to remove a tumor or to treat an intractable (difficult to cure) inflammation of the pancreas.
A parathyroidectomy is a removal of the parathyroid gland, usually to treat hyperparathyroidism.
Thyroidectomy is a removal of part or all of the thyroid gland to treat goiter, tumors, or hyperthyroidism that cannot be treated with medication. If most, but not all of this gland is removed, it will regenerate with normal function. In cancer, however, all of the gland must be removed. The procedure is called a total thyroidectomy.
Hypophysectomy
Mastering Healthcare Terminology/Chapter 15

35. Clicker Question
An A1c test is used to monitor treatment of which disorder?
A. Addison disease
B. Cushing disease
C. diabetes mellitus
D. diabetes insipidus
C. diabetes mellitus
Mastering Healthcare Terminology/Chapter 15

36. Pharmacology Antidiabetics Antithyroid agents Corticosteroids
Growth hormones
Posterior pituitary hormones
Thyroid hormones
Antidiabetics (also called hypoglycemic agents) encompass various oral agents and replacement insulin. They are used to manage glucose levels in the body when the pancreas or insulin receptors are no longer functioning properly. Type 1 diabetes mellitus typically requires insulin therapy, and management of type 2 diabetes mellitus begins with an oral antidiabetic such as metformin (Glucophage), glipizide (glucotrol), or rosiglitazone (Avandia); insulin is used as a last resort.
Antithyroid agents are used to treat hyperthyroidism. Examples include methimazole (Tapazole) and propylthiouracil (PTU).
Corticosteroids are used to treat underfunctioning adrenal cortices (Addison disease). An example is prednisone (Deltasone).
Growth hormones are drugs that are used to treat various disease-causing growth inhibitions. Examples include somatropin (Genotropin, Nutropin) and somatrem (Proptropin).
Posterior pituitary hormones such as vasopressin and desmopressin acetate are used to treat diabetes insipidus.
Thyroid hormones are drugs that are used to treat hypothyroidism. Examples include natural thyroid hormones (Armour Thyroid) and levothyroxine (Levoxyl, Synthroid).
Mastering Healthcare Terminology/Chapter 15

37. Pharmacology (cont’d)
Antidiabetics
Discuss the need for a variety of injection sites for patients requiring insulin.
Using the diagrams, discuss the advantage of the insulin pump.
Insulin pump
Insulin injection sites
Mastering Healthcare Terminology/Chapter 15

38. Insulin Pumps and Glucose Monitoring

39. Insulin Pump v. Insulin Injections:
Ø The first and most obvious advantage with using an insulin pump is there is no need for painful individual injections. The pump is conveniently worn around your waist and a small cannula, attached to an infusion set, is inserted under the skin allowing for easier diabetes management. Instead of multiple injections per day, the cannula is changed every 3 days.
Insulin pumps are more accurate than traditional injections and give you the freedom to live the way you want by having a continual delivery of insulin. Whether you are facing a tough week at work or running a marathon, the insulin pump allows you more freedom without having to calculate insulin to make up for a high carbohydrate meal or excessive exercise, and the pump also prevents severely low blood sugar.
The pump can also be adjusted so you have even better control over your health and can monitor the correct dosages based on your blood sugar allowing better control and fewer swings in blood glucose levels. This greatly reduces the risk of dangerously low blood sugar.

40. Did You Know?
Some pharmacologic therapy can cure one disease while causing another. For example, long-term cortisone use, such as that for patients with Crohn disease or ulcerative colitis, can result in Addison disease.

41. Clicker Question Vasopressin and desmopressin are used to treat:
A. diabetes insipidus
B. diabetes mellitus
C. Addison disease
D. hyperthyroidism
A. diabetes insipidus
Mastering Healthcare Terminology/Chapter 15

42. Sort these terms into their correct categories
1. neurohypophysis
2. hirsutism
3. hyponatremia
4. A1c
5. hypophysectomy
Categories
__ A+P
__ Pathology
__ Diagnostic Procedures
__ Therapeutic Interventions
A+P--neurohypophysis
Pathology --hirsutism, hyponatremia
Dx --A1c
Tx --hypophysectomy

43. Parting Thought “Wheresoever you go, go with all your heart.”
–Confucius
Any questions?
Mastering Healthcare Terminology/Chapter 15