CCMA - Ch. 7 Endocrine System

The endocrine system

the endocrine system, along with stimulation from the nervous system, functions to maintain homeostasis in the body. This is done through the release of hormones into the bloodstream. Different hormones act upon specific body functions in order to return the body to homeostasis. Normal functioning of the endocrine system is important in keeping the hormone levels in the body in balance

Endocrine glands

located throughout the body and are triggered to release hormones in response to various stimuli

The endocrine system is dependent on the bloodstream for...

transporting hormonal messages to a target cell for action

Hormones

the chemicals that help in carrying information from one group of cells to another.

Hormones are involved in growth control, mood, system functions, metabolism, sexual maturity, and reproduction.

Illness and stress may vary and affect hormonal levels.

What are two types of glands that affect the endocrine system?

endocrine and exocrine

Exocrine glands

such as sweat glands or salivary glands, deliver their secretions directly onto a surface and are not part of the endocrine system

endocrine glands

make up the hormone system in the body, secrete hormones directly into the bloodstream

Once the hormones are in the blood stream,

they are carried to target cells to perform their functions

Endocrine glands include:

Hypothalamus, Pituitary, Pineal, Thyroid, Parathyroid, Thymus, Adrenals, Reproductive glands, Pancreas

Hypothalamus

It is present in the inferior mid portion of the brain and serves as a major connection between the nervous system and the endocrine system.

It controls the action of the pituitary gland

Pineal gland

It is present deep within the brain and is helpful in the excretion of melatonin.

Thyroid

It is present in the anterior neck and is butterfly-shaped.

The thyroid-stimulating hormone (TSH) stimulates the thyroid gland to produce the thyroid hormones triiodothyronine (T3) and thyroxine (T4).

The thyroid gland hormones are responsible for regulating metabolism.

Pancreas

It is located in the upper abdomen.

It maintains normal blood glucose levels through the secretion of insulin.

Pituitary Gland

It is present below the hypothalamus and is a pea-sized gland.

It secretes hormones that regulate multiple endocrine glands and is referred to as the "master gland."

It comprises anterior and posterior lobes.

Parathyroid gland

Present on the dorsal aspect of the thyroid gland

Releases hormones such as parathyroid and calcitonin, which are involved in the regulation of calcium levels in the blood

Thymus Gland

Present behind the upper portion of the sternum and secretes hormones that are involved in the stimulation of T-cell production

Present at birth; becomes bigger with age and begins to atrophy during puberty

Important for T-cell maturation

Adrenals

Present on the top of each kidney

Triangular-shaped with an outer layer (the adrenal cortex) and an inner body (the adrenal medulla)

Produce hormones that modulate stress response and regulate many body functions

Reproductive

Includes male and female gonads that produce sex hormones

Male gonads located in the scrotum; involved in the secretion of testosterone

Female gonads located in the pelvis; involved in the secretion of estrogen and progesterone

Female gonads include ovaries, which produce eggs or ova

Anterior pituitary produces hormones that include...

growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), prolactin (PRL), follicle-stimulating hormone (FSH), and luteinizing hormone (LH)

Posterior pituitary secretes...

oxytocin and antidiuretic hormone (ADH)

Oxytocin

helps in contraction of uterus during labor, and plays an essential role in stimulation of the flow of breast milk during breast feeding

secreted by posterior pituitary

Antidiuretic Hormone (ADH)

acts on the kidneys and regulates fluid and electrolyte balance

secreted by posterior pituitary

The pineal gland secretes...

melatonin, which is involved in the regulation of waking and sleeping patterns and also in seasonal reactions to alterations in the presence of sunlight.

Thyroid glad

This gland helps in controlling the metabolic rate and is an important factor that contributes to bone growth and nervous system development in children.

produces the thyroid hormones triiodothyronine (T3) and thyroxine (T4)

Parathyroid hormones...

promote calcium absorption from the gastrointestinal tract and stimulate the calcium re-absorption stored in the bone to maintain homeostasis

Calcitonin

parathyroid gland hormone

stimulates calcium deposition into the bones in the presence of excess calcium

The adrenal cortex secretes...

corticosteroids such as cortisol, aldosterone, and adrenal androgens that affect a broad range of bodily functions

The adrenal medulla secretes...

epinephrine or adrenaline that moderates the activation of the body's reaction to stress

Testosterone

Testosterone promotes sperm production and regulates the development of secondary sexual characteristics that include voice changes and the growth of facial and pubic hair.

Estrogen and progesterone

Estrogen and progesterone regulate breast tissue development and other secondary sexual characteristics. These hormones regulate menstruation and have important roles in pregnancy.

Insulin and glucagon

Insulin and glucagon help in maintaining normal blood glucose level and reserve glucose for energy.

hormones of pancreas

What regulates hormone production?

Nervous stimulation, endocrine control, and feedback systems; The most common feedback system is a negative feedback system

Negative feedback system for endocrine system

The most common feedback system is a negative feedback system, in which an imbalance activates an endocrine gland, which acts to correct the imbalance by ceasing the secretion process. In short, the negative feedback system is the response of the endocrine gland to hormonal imbalance.

Examples

Stimulation of parathyroid glands occurs to release the parathyroid hormone when calcium levels in the blood fall below normal.

Secretion of insulin occurs when glucose levels in the blood elevate to a level greater than normal.

Diseases and disorders of the endocrine system can result from...

Hormonal imbalance occurs when the negative feedback system is unable to maintain the normal levels of hormones; an infection, injury, genetic disorder, tumor, or lifestyle

The lack of ADH may cause

Insufficient or no production of ADH or vasopressin results in diabetes insipidus. Fluid reabsorption from the renal tubules does not take place without the action of ADH. This leads to a large amount of fluid excretion in the urine, with increased sodium levels in the blood, leading to severe (often fatal) dehydration.

Diabetes Insipidus

Insufficient or no production of ADH or vasopressin results in diabetes insipidus. Fluid reabsorption from the renal tubules does not take place without the action of ADH. This leads to a large amount of fluid excretion in the urine, with increased sodium levels in the blood, leading to severe (often fatal) dehydration. Therefore, sodium levels and fluid intake and output should be closely monitored. The permeability of the renal tubules and the collecting tubules in the kidneys increases in the presence of ADH. This allows fluid reabsorption, which prevents dehydration and leads to more concentrated urine

The presence of a kidney disease or the side effects of certain medications may also cause an inadequate response to ADH in the renal tubules, leading to diabetes insipidus

Diabetes insipidus symptoms

Diabetes insipidus occurs abruptly. It is characterized by polyuria, polydipsia, nocturia, urine of low specific gravity, and high blood plasma osmolality. It may cause fatal dehydration if not treated on time.

Insufficient or underproduction of Growth Hormone from the pituitary gland causes...

hypopituitary dwarfism. In this condition, the child will have impaired height, but head and trunk are of normal size.

In children, hypersecretion of Growth Hormone before the closing of the epiphyseal plates in the long bones leads to...

excessive growth of long bones. This is called gigantism. The children may reach a height of 8 feet or more and may develop diabetes mellitus as a secondary effect.

In adults, over-secretion of Growth Hormone causes...

acromegaly. Due to the closure of the epiphyseal plates, there is no growth of long bones, but the bones of the jaw, face, hands, and feet show a gradual and noticeable enlargement.

Signs and symptoms of acromegaly include...

Signs and symptoms of acromegaly include arthralgia, an enlarged tongue, overactive sebaceous and sweat glands, coarse skin, excessive body hair, and nerve damage.

Complications of advanced acromegaly...

Complications of advanced acromegaly includes congestive heart failure, Diabetes Mellitus, cerebrovascular abnormalities, and neurologic symptoms.

Hypothyroidism

A reduction in the thyroid hormones causes lower metabolic rate, heat loss, and poor mental and physical development.

What can lead to the underproduction of thyroid hormones?

Dietary deficiency of iodine, congenital atrophy of the thyroid gland, and infection may lead to underproduction of thyroid hormones.

Symptoms of hypothyroidism include...

Symptoms include fatigue, weight gain, hair loss, a slower pulse rate, a lowered body temperature, muscle cramps, menorrhagia, and thick, dry, puffy skin.

A simple goiter refers to...

A simple goiter refers to the enlargement of any thyroid, which is not due to an infection or neoplasm.

cretinism

Congenital hypothyroidism can lead to cretinism, characterized by feeding problems, constipation, a hoarse cry, and sleep for extreme lengths of time. In addition, newborns may experience lethargy, bradycardia, stunted skeletal growth, and varying degrees of developmental delays.

Myxedema

Severe or chronic hypothyroidism in an adult or older child refers to myxedema.

Diagnostic tests for hypothyroidism are

Diagnostic tests for hypothyroidism are radioimmunoassay for T3, T4, and TSH.

A simple goiter can be reduced to its size by

A simple goiter can be reduced to its size by taking dietary supplements of iodine, thyroid hormone replacement, or surgery.

Treatments for hypothyroidism include...

Medications for restoring normal function and appearance of the thyroid include sufficient doses of thyroxine (Levothroid, Levoxyl, or Synthroid).

Hormone replacement therapy should be taken daily for the rest of the life and thyroid function tests should be performed once in a year.

The provider may instruct the patient to include saltwater fish, seaweed, and grains in the diet, as these are the primary sources of dietary iodine.

Goiter

Goiter is an enlargement of the thyroid gland, not due to infection or neoplasm. It is common to both hypothyroidism and hyperthyroidism, but with some differences.

Goiter in Hypothyroidism

Associated with other signs and symptoms of hypothyroidism such as fatigue, weight gain, hair loss, a slower pulse rate, a lowered body temperature, muscle cramps, menorrhagia, and thick, dry, puffy skin

Usually treated with iodine supplementation and thyroid hormone replacement

Goiter in Hyperthyroidism

Associated with other signs and symptoms of hyperthyroidism such as weight loss, tachycardia, palpitations, hypertension, agitation, nervousness, depression, tremor, excessive sweating, and exophthalmia

Usually treated with administering of anti-thyroid medications and radioactive iodine

Hyperthyroidism

Weight loss, goiter (enlarged thyroid), and protruding eyes are common symptoms of hyperthyroidism.

Excess serum levels of thyroid hormones lead to thyrotoxicosis or hyperthyroidism.

Patients with hyperthyroidism report...

Patients with hyperthyroidism report weight loss, tachycardia, palpitations, hypertension, agitation, nervousness, depression, tremor, excessive sweating, goiter, and exophthalmia (protruding eyes).

Treatment of hyperthyroidism includes...

Treatment of hyperthyroidism includes administering of antithyroid medications propylthiouracil (PTU) and methimazole (Tapazole), treating with radioactive iodine, and surgical thyroidectomy.

Treatment of hyperthyroidism may result in...

Treatment of hyperthyroidism may result in hypothyroidism, so the thyroid levels should be monitored after treatment.

When thyroid levels are normal after treatment...

he provider instructs the patient to take hormone replacement therapy (Levothroid, Levoxyl, or Synthroid).

Orbital decompression surgery

Orbital decompression surgery is helpful in patients who develop exophthalmia from hyperthyroidism.

Addison's disease

Potassium retention and the excretion of water and sodium in the urine occur due to cortisol and aldosterone deficiency, leading to severe dehydration, low blood volume, low blood pressure, and circulatory shock.

Caused by insufficiency of adrenal glands. caused by an autoimmune reaction that affects the adrenal cortex

The treatment of Addisonian crisis requires immediate administration of an intravenous saline and dextrose solution and corticosteroids.

Addison's disease symptoms

Is characterized by hypoglycemia, increased skin pigmentation, muscle weakness, gastrointestinal disturbances, and fatigue.

What can increase risk for Addison's disease

Stress, surgery, infection, and minor illness may increase the risk of Addisonian crisis manifested as a life-threatening drop in blood pressure, hypoglycemia, and elevated blood potassium levels.

Treatment for Addison's disease

Treatment of Addison's disease includes replacing cortisol with the long-term daily administration of glucocorticoids (e.g., prednisone), and replacing aldosterone with fludrocortisone (Florinef).

Inclusion of complex carbohydrates and protein in the diet and maintaining sufficient fluid intake also helps.

Hyperpigmentation in Addison's Disease

Associated with manifestations such as hypoglycemia, muscle weakness, gastrointestinal disturbances, and fatigue

Hyperpigmentation is seen in both Addison's disease and Cushing's syndrome, but is more common in Addison's disease.

Hyperpigmentation in Cushing's Syndrome

Associated with manifestations such as muscle wasting, wound healing problem, hypertension, kidney stones, and osteoporosis

Hyperpigmentation is seen in both Addison's disease and Cushing's syndrome, but is more common in Addison's disease.

Cushing's syndrome

Cushing's Syndrome is characterized by accumulation of adipose (fat) tissue in the body or trunk. The symptoms include muscle wasting, hypertension, and osteoporosis.

Hyper-secretion of the adrenal cortex results in elevated levels of cortisol. The release of excessive amounts of ACTH may be due to a benign pituitary tumor.

Cushing's syndrome symptoms

It is characterized by accumulation of adipose (fat) tissue in the body or trunk, leading to characteristics like "moon face" and "buffalo hump." Symptoms of Cushing's syndrome include hyperpigmentation, muscle wasting, wound healing problem, hypertension, kidney stones, and osteoporosis.

Cushing's Syndrome treatment?

reatment varies with the cause of the disorder and include:

Medication for controlling cortisol levels

Radiation therapy for reduction of tumor size

Surgery for tumor removal

Cushing's syndrome co-morbidities

The co-morbidities include mental disorders such as irritability, depression, or severe psychiatric disorders, and menstrual irregularities in females.

Who is at a higher risk for Cushing's syndrome?

Individuals on corticosteroid therapy for organ transplantation, severe asthma, or rheumatoid arthritis report symptoms of Cushing's syndrome.

Diabetes mellitus

a hormonal disorder of the pancreas that can occur in people of all ages and races. It is more common in people of age above 60.

occurs due to insufficient insulin production or insulin resistance at target cells

Chronic hyperglycemia and problems with carbohydrate metabolism occur due to diabetes mellitus.

Diabetes mellitus can be of various types. When untreated or unmanaged, it can lead to life-threatening consequences.

In all types of diabetes, active patient involvement helps in the management of the disease. The goal of diabetes management is to maintain close to normal blood glucose levels.

Diabetes mellitus is characterized by

It is characterized by Carbohydrate metabolism problems, Hyperglycemia, glycosuria, polyuria, polydipsia, polyphagia, rapid weight loss, drowsiness, fatigue, itching of the skin, visual disturbances, and skin infections.

Factors that increase the risk of developing DM:

Heredity: People with a family history of DM are at a greater risk of developing DM. So are people of certain ancestry such as African Americans, Latinos, Native Americans, and Asian Americans or Pacific Islanders.

Obesity: The increase of fat around the waist increases insulin resistance and the risk of DM.

Physical inactivity: A sedentary lifestyle reduces the use of insulin by the body's cells.

Autoimmune reaction: An autoimmune reaction destroys the islet cells, increasing the risk of type 1 DM.

Prediabetes

Prediabetes: This type of diabetes presents no symptoms in the early stage and, therefore, blood tests are helpful for the diagnosis. About 15% to 30% of prediabetes patients develop DM type 2 within 5 years without alteration in lifestyle.

Diabetes mellitus type 1

Diabetes mellitus type 1: This type of diabetes was also known as juvenile-onset diabetes or insulin-dependent diabetes, and occurs most often in children and young adults. Symptoms develop abruptly, and the individual becomes very ill within a short time. Patients with diabetes mellitus type 1 need insulin injections daily to maintain normal blood glucose levels.

Diabetes mellitus type 2

Diabetes mellitus type 2: This type of diabetes is known as adult-onset or non-insulin-dependent diabetes. Pathophysiology of DM type 2 involves a family history, a history of gestational diabetes, impaired glucose tolerance, physical inactivity, and obesity. This type of DM has a slow onset of hyperglycemia, and there are no classic symptoms; hence it remains undetected for years. This type of DM is common among 60-plus African Americans, Latinos, and native Americans.

Gestational Diabetes

Gestational diabetes: This type of diabetes is from insulin resistance at the cellular level, causing hyperglycemia. Increased glucose levels in the mother's blood cross the placenta and enters into the baby, thereby causing hyperglycemia, with excess insulin production in the fetus. Some women do not show symptoms, and others show classic symptoms of diabetes. Women with gestational diabetes are at risk of developing DM type 2 within 5 to 10 years.

Diabetes mellitus, if left untreated or poorly controlled, can cause serious, life-threatening complications, including:

Cardiovascular disease and hypertension

Ictus

Renal disease

Blindness

Nervous system disorders

Amputations

Pregnancy complications

Diabetic coma

Hypoglycemia

acute complications of diabetes mellitus.

This occurs if the patient's blood glucose levels drop below 70 mg/dL.

Signs and symptoms include tremors, dizziness, palpitations, diaphoresis, headache, hunger, pallor, fatigue, confusion, irritability, poor judgment, visual disturbances, convulsions and coma.

Treatment of hypoglycemia includes four steps:

Glucose tablets containing 5 g of glucose are recommended to treat urgent cases of hypoglycemia. Administer 15 g of carbohydrates (3 glucose tablets) immediately, while the patient is conscious.

Wait 15 minutes and recheck the reading. If the level is still low, repeat the first step.

Once the symptoms are relieved, let the patient eat a normal meal.

If symptoms persist, inject glucagon to quickly raise blood sugar levels.

Diabetic Ketoacidosis

acute complications of diabetes mellitus.

This occurs when a person with diabetes is unable to use glucose as a source of energy due to the absence or insufficiency of insulin. It can become a medical emergency if symptoms are not recognized and treated in time.

Blood glucose levels increase from 300 to 750 mg/dL, resulting in hyperglycemia.

The body's cells cannot use carbohydrates as a source of energy and begin to burn fat, releasing ketones as a byproduct.

Ketones increase in the bloodstream, making it acidic, leading to diabetic ketoacidosis.

Chronic complications of diabetes

develop gradually and cause microvascular and macrovascular diseases.

Microvascular diseases include

diabetic retinopathy, diabetic nephropathy and diabetic neuropathy

Macrovascular diseases

are due to atherosclerotic changes and include coronary artery disease and peripheral vascular disease. The combination of all these factors delays wound healing.

Diabetic retinopathy

Diabetic retinopathy involves changes in the retinal capillaries and causes visual disturbances, retinal detachment and blindness. Adequate control of glucose levels can delay the onset of retinopathy.

Episodes of hyperglycemia damage the retinal blood vessels, leading to the onset of diabetic retinopathy.

Patients with diabetes should undergo annual eye examinations and frequent ophthalmological examinations to diagnose retinopathy as early as possible to prevent the risk of glaucoma and cataracts.

Diabetic nephropathy

Diabetes affects the small blood vessels in the kidneys and hinders the filtration process. Degenerative changes may affect the glomerular unit and cause renal failure.

Patients with type I diabetes mellitus, compared to those with type 2 diabetes mellitus, have an increased risk of diabetic kidney disease.

Frequent albuminuria testing helps diagnose kidney disease, as urinary protein is the first sign of kidney disease.

Further progression of the disease may cause kidney failure and require dialysis or kidney transplantation.

Diabetic Neuropathy

Diabetic neuropathy is the most common complication affecting most diabetic patients. Nerve damage caused by both vascular changes and hyperglycemia.

The patient loses the ability to react to injuries due to loss of sensation in the extremities.

Macrovascular disease

Atherosclerosis is the most common health problem in patients with diabetes mellitus.

Coronary artery disease involves atherosclerotic changes in the blood vessels of the heart, and is the leading cause of death in patients with diabetes mellitus.

Peripheral vascular disease involves atherosclerotic changes in small arteries and arterioles, leading to gangrene and amputation of fingers, feet and legs.

Infection

Many factors increase the risk of infection and delayed wound healing in diabetic patients.

Impaired vision and neuropathies increase the risk of injury and compromise skin integrity.

Damaged or atherosclerotic blood vessels cannot supply blood for healing and thickened vessel walls obstruct the release of white blood cells (WBCs) to the site of injury.

The ability to destroy pathogens is reduced in diabetic patients, and some pathogens multiply in glucose-rich environments.

Injuries to the feet cause ulcers or diabetic lesions that can lead to gangrene and amputation.

glycosylated hemoglobin (HbA1c) test

the best test used to monitor the long-term treatment of diabetes. This test shows serum glucose control over several months. The test measures glucose levels chemically bound to the red blood cell (RBC) hemoglobin molecule for 120 days. The patient's total HbA1c should be less than 7%. An increase in the glycosylated hemoglobin value will increase the risk of diabetic complications.

The best method to prevent diabetes complications is to

keep glucose levels constant. The physician orders a fasting blood glucose test to monitor glucose levels. The patient should continue to check blood glucose levels with a home glucometer.

Self-management of diabetes may include

regular monitoring of blood glucose levels, following a balanced diet, staying physically active and leading a healthy lifestyle.

Diabetic Patient Plan: Medication

To help the patient understand oral hypoglycemic agents, their doses, side effects and management.

Educate the patient on the importance of medication compliance.

Provide patient assistance and education on safe insulin administration.

Diabetic Patient Plan: Lifestyle

Teach the patient that physical activity, stress, illness, medications and diet affect blood glucose levels.

Check the patient's weight and height and provide information on nutritional needs.

Diabetic Patient Plan: Self-care

When educating a patient with diabetes, the MA should ensure that the patient understands the procedure for home treatment.

Demonstrating the procedure and responding to the patient's questions or concerns about the treatment process are helpful in teaching self-management. Visual materials, such as brochures and procedure cards, help remind patients of the treatment.

Ensure that the patient accurately uses the glucometer and understands the complications of the disease. You must first demonstrate its use to the patient and then ask the patient to return the demonstration.

Diabetic Patient Plan: Support Group

Provide information to the patient about support groups and online resources available for guidance. Diabetic education classes are also offered in some clinics.

If possible, involve the patient's family members in teaching dietary health education.

Involve a community educator in patient education.

Diabetic patients should also be taught to recognize the symptoms of very high and very low blood sugar levels.

Very low blood sugar, or hypoglycemia, can lead to disorientation or even coma and death. Many patients with diabetes wear a medical alert bracelet, which indicates that they have a medical problem. This bracelet is worn at all times and has a description of the medical condition on the back. Having a medical alert bracelet can help to quickly provide the most appropriate care in an emergency situation.