Endocrine System and Disorders

These flashcards cover key vocabulary and concepts related to the endocrine system and its disorders, enabling effective study and review.

Endocrine System

A system of glands that secrete hormones directly into the bloodstream to regulate various body functions.

Hormones

Chemical messengers released by endocrine glands that regulate physiological processes in the body.

Negative Feedback System

A regulatory mechanism where an increase in a hormone's levels leads to a decrease in its production, and vice versa.

Hypothyroidism

A condition characterized by low levels of thyroid hormones, typically leading to slowed metabolic processes.

Hyperthyroidism

A condition characterized by excessive levels of thyroid hormones, leading to an accelerated metabolism.

Acromegaly

A disorder resulting from excess growth hormone in adulthood, causing enlargement of bones and tissues.

Giantism

A condition resulting from excessive growth hormone in children before epiphyseal plate closure, leading to increased height.

Diabetes Insipidus

A disorder caused by insufficient release of ADH, leading to excessive urination and thirst.

Syndrome of Inappropriate Antidiuretic Hormone (SIADH)

A condition characterized by excessive release of ADH, leading to water retention and hyponatremia.

Pheochromocytoma

A tumor of the adrenal gland that results in excess production of catecholamines, causing high blood pressure and other symptoms.

Addison's Disease

A disorder characterized by insufficient production of adrenal hormones, leading to various symptoms including fatigue and weight loss.

Cushing's Syndrome

A condition caused by excess cortisol production, often leading to symptoms such as obesity, hypertension, and skin changes.

Thyroid Stimulating Hormone (TSH)

A hormone produced by the pituitary gland that stimulates the thyroid gland to produce thyroid hormones.

Adrenocorticotropic Hormone (ACTH)

A hormone produced by the pituitary gland that stimulates the adrenal cortex to release cortisol.

Parathyroid Hormone (PTH)

A hormone that regulates calcium levels in the blood, increasing calcium levels by acting on bone, kidney, and intestine.

Calcitonin

A hormone secreted by the thyroid that lowers blood calcium levels by promoting calcium deposition in bones.

Hypoparathyroidism

A condition caused by insufficient secretion of parathyroid hormones, leading to low calcium levels in the blood.

Hyperparathyroidism

A condition characterized by excessive secretion of parathyroid hormone, resulting in high calcium levels.

What is the Endocrine System and what is its primary function?

The Endocrine System is a complex network of glands that produce and secrete hormones directly into the bloodstream. Its primary function is to regulate various critical bodily processes such as metabolism, growth and development, tissue function, sexual function, reproduction, sleep, and mood.

What are Hormones and how do they function as chemical messengers?

Hormones are potent chemical messengers produced by endocrine glands. They travel through the bloodstream to target cells or organs, where they bind to specific receptors and regulate a wide array of physiological processes, ensuring the body maintains homeostasis.

Explain the concept of a Negative Feedback System in the context of hormone regulation.

A Negative Feedback System is a crucial regulatory mechanism where the body responds to a stimulus in a way that counteracts it, maintaining stable conditions (homeostasis). In endocrinology, if the levels of a hormone rise too high, this system triggers a response that decreases its production, and conversely, if levels drop too low, it stimulates an increase in production.

What is Hypothyroidism and what are its general effects on the body's metabolism?

Hypothyroidism is an endocrine condition characterized by an abnormally low production of thyroid hormones (thyroxine, T4, and triiodothyronine, T3) by the thyroid gland. This deficiency typically leads to a significant slowing of metabolic processes throughout the body, affecting energy levels, weight, and body temperature.

What is Hyperthyroidism and how does it affect the body's metabolism?

Hyperthyroidism is a condition marked by the excessive production and release of thyroid hormones (T3 and T4) from the thyroid gland. This overactivity leads to an accelerated metabolic rate, resulting in symptoms such as increased heart rate, weight loss despite increased appetite, and heat intolerance.

What is Acromegaly and when does it typically manifest?

Acromegaly is a hormonal disorder that results from the chronic overproduction of growth hormone (GH) in adulthood after the epiphyseal growth plates have closed. This excess GH causes the enlargement of bones and soft tissues, primarily in the hands, feet, and face, without an increase in height.

What is Giantism and how does it differ from Acromegaly?

Giantism is a rare condition caused by excessive secretion of growth hormone (GH) during childhood or adolescence, before the closure of the epiphyseal growth plates. This leads to abnormally rapid and excessive growth in height, making individuals significantly taller than average, differentiating it from Acromegaly which occurs after growth plates have fused.

Describe Diabetes Insipidus, including its cause and main symptoms.

Diabetes Insipidus (DI) is a rare disorder caused by the insufficient release or impaired action of antidiuretic hormone (ADH), also known as vasopressin, from the posterior pituitary gland or the kidneys' inability to respond to ADH. This deficiency leads to the kidneys being unable to conserve water, resulting in excessive urination (polyuria) and intense thirst (polydipsia).

What is Syndrome of Inappropriate Antidiuretic Hormone (SIADH) and its primary physiological effects?

Syndrome of Inappropriate Antidiuretic Hormone (SIADH) is a condition characterized by the excessive and inappropriate release of antidiuretic hormone (ADH) from the posterior pituitary gland, regardless of the body's osmotic balance. This leads to the kidneys retaining too much water, resulting in water retention, dilutional hyponatremia (low sodium in the blood), and decreased urine output.

What is a Pheochromocytoma and what are its key effects?

A Pheochromocytoma is a rare, usually benign tumor that develops in the adrenal medulla, which is part of the adrenal gland. This tumor causes the adrenal gland to produce excessive amounts of catecholamines (epinephrine and norepinephrine), leading to paroxysmal or sustained high blood pressure, palpitations, headaches, and sweating.

Define Addison's Disease and list its causative factor and common symptoms.

Addison's Disease, also known as primary adrenal insufficiency, is a rare and potentially life-threatening disorder caused by the insufficient production of steroid hormones (cortisol and often aldosterone) by the adrenal cortex. This deficiency leads to a variety of symptoms including chronic fatigue, muscle weakness, weight loss, low blood pressure, and distinctive skin hyperpigmentation.

What is Cushing's Syndrome and what is its primary hormonal cause and associated symptoms?

Cushing's Syndrome is a condition characterized by prolonged exposure to high levels of cortisol, a glucocorticoid hormone. It is most commonly caused by an adrenal tumor, pituitary tumor (Cushing's disease), or prolonged use of corticosteroid medications. Symptoms typically include central obesity, a "moon face," "buffalo hump," hypertension, hyperglycemia, muscle weakness, and fragile skin.

What is Thyroid Stimulating Hormone (TSH) and what is its role in thyroid function?

Thyroid Stimulating Hormone (TSH), also known as thyrotropin, is a hormone produced and released by the anterior pituitary gland. Its crucial role is to stimulate the thyroid gland to produce and secrete its own hormones, primarily thyroxine (T4) and triiodothyronine (T3), thereby regulating the body's metabolism.

What is Adrenocorticotropic Hormone (ACTH) and what gland does it target?

Adrenocorticotropic Hormone (ACTH), also known as corticotropin, is a polypeptide hormone produced and secreted by the anterior pituitary gland. Its main function is to stimulate the adrenal cortex, the outer part of the adrenal gland, to release glucocorticoids, especially cortisol, in response to stress.

What is Parathyroid Hormone (PTH) and how does it regulate calcium levels?

Parathyroid Hormone (PTH) is a hormone secreted by the parathyroid glands. It plays a vital role in regulating and increasing calcium levels in the blood. It achieves this by acting on three primary targets: stimulating calcium release from bones, increasing calcium reabsorption in the kidneys, and indirectly increasing calcium absorption in the intestines via vitamin D activation.

What is Calcitonin and what is its role in calcium homeostasis?

Calcitonin is a hormone secreted by the parafollicular cells (C cells) of the thyroid gland. Its primary role in calcium homeostasis is to lower high blood calcium levels by promoting the deposition of calcium into bones and inhibiting its reabsorption from the kidneys, thus acting antagonistically to Parathyroid Hormone (PTH).

What is Hypoparathyroidism and what are its effects on blood calcium?

Hypoparathyroidism is an endocrine disorder caused by the insufficient secretion or absence of parathyroid hormone (PTH) from the parathyroid glands. This deficiency leads to abnormally low levels of calcium in the blood (hypocalcemia) and increased phosphate levels, which can cause symptoms such as muscle cramps, spasms (tetany), and tingling sensations.

What is Hyperparathyroidism and how does it impact blood calcium levels?

Hyperparathyroidism is a condition characterized by the excessive secretion of parathyroid hormone (PTH) by one or more of the parathyroid glands. This overproduction of PTH results in abnormally high levels of calcium in the blood (hypercalcemia), which can lead to weakened bones, kidney stones, abdominal pain, and fatigue.

What are the primary signs and symptoms, common medications, and essential nursing interventions for the management of Hyperthyroidism?

Signs & Symptoms:

• Weight loss: Unexplained decrease in body weight despite normal or increased food intake due to accelerated metabolism.

• Increased appetite: Enhanced hunger often accompanying weight loss.

• Heat intolerance: Difficulty tolerating warm environments due to increased body heat production.

• Tremors: Fine tremors, especially in the hands.

• Palpitations: Awareness of rapid, strong, or irregular heartbeats.

• Anxiety: Increased nervousness, irritability, and restlessness.

• Exophthalmos (bulging eyes): Protrusion of one or both eyeballs, a distinctive sign particularly in Graves' disease.

Medications:

• Antithyroid drugs: Such as methimazole and propylthiouracil, which reduce the production of thyroid hormones.

• Beta-blockers: Medications like propranolol, used to manage adrenergic symptoms (e.g., palpitations, tremors, anxiety) but do not affect hormone levels.

Nursing Interventions:

• Monitor vital signs: Closely track heart rate, blood pressure, and temperature for signs of complications or medication effectiveness.

• Provide a cool environment: Help manage heat intolerance by ensuring a comfortable room temperature and adequate ventilation.

• Promote rest: Encourage periods of rest and sleep to counteract the hypermetabolic state and conserve energy.

• Administer medications as ordered: Ensure timely and accurate administration of antithyroid drugs and symptomatic relief medications.

• Educate patient on symptoms and medication adherence: Instruct patients on recognizing worsening symptoms and the importance of consistent medication use.

• Monitor for thyroid storm: Be vigilant for signs of this life-threatening acute exacerbation of