Chapter 16

LH

luteinizing hormone

isthmus

narrow strip of tissue connecting two larger parts in the body, such as the isthmus that connects the two lobes of the thyroid gland

euglycemia

normal (level of) sugar in the blood (within normal range)

sestamibi parathyroid scan

nuclear medicine procedure used to localize hyperactive parathyroid glands. The glands that take up an abnormal amount of radioactive substance are identified and selected for surgical removal; the other parathyroid glands may be left in place.

adrenal glands

paired glands, one of which is located superior to each kidney. The outer portion is called the adrenal cortex, and the inner portion is called the adrenal medulla. The following hormones are secreted by the adrenal glands:

parathyroid/o

parathyroid glands

cortical

pertaining to the cortex

endocrinologist

physician who studies and treats diseases of the endocrine system

pituitar/o

pituitary gland

fasting blood sugar (FBS)

blood test to determine the amount of glucose (sugar) in the blood after fasting for 8-10 hours. Elevation may indicate diabetes mellitus.

glycosylated hemoglobin (HbA1C)

blood test used to diagnose diabetes and monitor its treatment by measuring the amount of glucose (sugar) bound to hemoglobin in the blood. HbA1C provides an indication of blood sugar level over the past three months, covering the 120-day lifespan of the red blood cell (also called glycated hemoglobin, hemoglobin A1C, and A1C test).

hormone

chemical substance secreted by an endocrine gland that is carried in the blood to a target tissue

diabetes mellitus

chronic disease involving a disorder of carbohydrate metabolism caused by under-activity of the insulin-producing islets of Langerhans and characterized by elevated blood sugar (hyperglycemia). DM can cause chronic renal disease, retinopathy, and neuropathy. In extreme cases the patient may develop ketosis, acidosis, and finally coma.

hypercalcemia

excessive calcium in the blood

hyperkalemia

excessive potassium in the blood

hyperglycemia

excessive sugar in the blood

parathyroidectomy

excision of (one or more) parathyroid glands

adrenalectomy

excision of the adrenal glands

pancreatectomy

excision of the pancreas

thyroidectomy

excision of the thyroid gland

acr/o

extremities, height

FBS

fasting blood sugar

FNA

fine needle aspiration

FSH

follicle-stimulating hormone

parathyroid glands

four small bodies embedded in the posterior aspect of the lobes of the thyroid gland. Parathyroid hormone (PTH), the hormone produced by the glands, helps maintain the level of calcium in the blood by its effects on bone and kidneys.

HbAC1

glycosylated hemoglobin

Cushing's syndrome

group of signs and symptoms attributed to the excessive production of cortisol by the adrenal cortices (pl. of cortex). This syndrome may be the result of a pituitary tumor that produces ACTH or a primary adrenal cortex hypersecretion. Signs include abnormally pigmented skin, "moon face," pads of fat on the chest and abdomen, "buffalo hump" (fat on the upper back), wasting away of muscle, and hypertension.

metabolic syndrome

group of signs and symptoms including insulin resistance, obesity characterized by excessive fat around the area of the waist and abdomen, hypertension, hyperglycemia, elevated triglycerides, and low levels of the "good" cholesterol HDL. Risks include development of type 2 diabetes mellitus, coronary heart disease, or stroke (also called syndrome X and insulin resistance syndrome).

GH

growth hormone

anterior lobe

produces and secretes the following hormones (also called adenohypophysis):

PRL

prolactin

Prolactin (PRL)

promotes development of glandular tissue during pregnancy and produces milk after birth of an infant

RAIU

radioactive iodine uptake

Growth Hormone (GH)

regulates the growth of the body

euthyroid

resembling a normal thyroid gland

corticoid

resembling the cortex

diabetes insipidus (DI)

result of decreased secretion of antidiuretic hormone by the posterior lobe of the pituitary gland. Symptoms include excessive thirst (polydipsia), large amounts of urine (polyuria), and water being excreted from the body

syndrome

run together (signs and symptoms occurring together that are characteristic of a specific disorder)

aldosterone

secreted by the adrenal cortex. Electrolytes (mineral salts) that are necessary for normal body function are regulated by this hormone.

cortisol

secreted by the adrenal cortex. It aids the body during stress by increasing glucose levels to provide energy (also called hydrocortisone).

epinepherine and norepinepherine

secreted by the adrenal medulla. These hormones help the body to deal with stress by increasing the blood pressure, heartbeat, and respirations. (also called adrenaline and noradrenaline, respectively)

ketoacidosis

serious condition resulting from uncontrolled diabetes mellitus in which acid ketones accumulate from fat metabolism in the absence of adequate insulin. If not promptly controlled by adequate insulin and hydration, can progress to coma and death.

Hypopituitarism

state of deficient pituitary gland activity (characterized by decreased secretion of one or more of the pituitary hormones, which can affect the function of the target endocrine gland; for example, hypothyroidism can result from decreased secretion of thyroid-stimulating hormone by the pituitary gland)

Hypothyroidism

state of deficient thyroid gland activity (characterized by decreased secretion of thyroid hormones. Signs and symptoms include fatigue, weight gain, and cold intolerance.)

hyperparathyroidism

state of excessive parathyroid gland activity (resulting in hypercalcemia and leading to osteoporosis, as well as symptoms of muscle weakness, abdominal pain, nausea, vomiting, and drowsiness)

hyperpituitarism

state of excessive pituitary gland activity (characterized by excessive secretion of pituitary hormones)

hyperthyroidism

state of excessive thyroid gland activity (characterized by excessive secretion of thyroid hormones. Signs and symptoms include weight loss, irritability, and heat intolerance.)

panhypopituitarism

state of total deficient pituitary gland activity (characterized by decreased secretion of all the anterior pituitary hormones; this is a more serious condition than hypopituitarism in that it affects the function of all the other endocrine glands)

gonadotropic hormone

stimulate the gonads (the testes in males and ovaries in females). Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are the gonadotropic hormones released from the adenohypophysis.

adrenocorticotropic hormone (ACTH)

stimulates the adrenal cortex

antidiuretic hormone (ADH)

stimulates the kidney to reabsorb water and constricts blood vessels to help maintain blood pressure (also called vasopressin)

thyroid-stimulating hormone (TSH)

stimulates thyroid gland

oxytocin

stimulates uterine contractions during labor and postpartum, and milk let down by the breasts postpartum

posterior lobe

stores and releases antidiuretic hormone and oxytocin (also called neurohypophysis)

endocrinology

study of the endocrine (system) (a branch of medicine dealing with diseases of the endocrine system)

glycemia

sugar in the blood

metabolism

sum total of all the chemical processes that take place in a living organism

dips/o

thirst

thyr/o, thyroid/o

thyroid gland

TSH

thyroid-stimulating hormone

T4

thyroxine level

parathyroidoma

tumor of a parathyroid gland

calc/i

Calcium

kal/i

Potassium

natr/o

Sodium

Thyroid Stimulating Hormone (TSH) level

blood test that measures the amount of thyroid-stimulating hormone in the blood; used to diagnose hypothyroidism and to monitor patients on thyroid replacement therapy

Incretins

a group of hormones produced by the gastrointestinal system that stimulate the release of insulin from the pancreas and help preserve the beta cells. Incretin mimetics are medications that copy this action and help control blood sugar in patients with type 2 diabetes mellitus.

exophthalmos

abnormal protrusion of the eyeball

polydipsia

abnormal state of much thirst

adren/o, adrenal/o

adrenal glands

ACTH

adrenocorticotropic hormone

ADH

antidiuretic hormone

endocrinopathy

any disease of the endocrine system

pituitary gland

approximately the size of a pea and located at the base of the brain. The pituitary is divided into two lobes. It is often referred to as the master gland because it produces hormones that stimulate the function of other endocrine glands (also called hypophysis cerebri)

graves disease

autoimmune disorder of the thyroid gland characterized by the production of more thyroid hormone than the body needs (hyperthyroidism), goiter, and exophthalmos (abnormal protrusion of the eyeballs)

fine needle aspiration (FNA)

biopsy technique that uses a narrow hollow needle to obtain tiny amounts of tissue for pathologic examination. Thyroid nodules are frequently biopsied using FNA.

thyroxine level (T4)

blood test that gives the direct measurement of the amount of thyroxine in the patient's blood. A greater-than-normal amount indicates hyperthyroidism; a less-than-normal amount indicates hypothyroidism.

Addison disease

chronic syndrome resulting from a deficiency in the hormonal secretion of the adrenal cortex. Signs and symptoms may include weakness, weight loss, hypotension, darkening of skin, and loss of appetite.

islets of langerhans

clusters of endocrine tissue found throughout the pancreas, made up of different cell types that secrete various hormones, including insulin and glucagon. Non-endocrine cells found throughout the pancreas produce enzymes that facilitate digestion

tetany

condition affecting nerves causing muscle spasms as a result of low amounts of calcium in the blood caused by a deficiency of the parathyroid hormone

gigantism

condition brought about by hypersecretion of growth hormone by the pituitary gland before puberty

congenital hypothyroidism

condition caused by congenital absence or atrophy (wasting away) of the thyroid gland, resulting in hypothyroidism. The disease is characterized by puffy features, mental deficiency, large tongue, and dwarfism.

thyrotoxicosis

condition caused by excessive thyroid hormones

myxedema

condition resulting from an extreme deficiency of the thyroid hormone thyroxine; a severe form of hypothyroidism in an adult. Signs include puffiness of the face and hands, coarse and thickened skin, enlarged tongue, slow speech, and anemia.

cortic/o

cortex (the outer layer of a body organ)

hypocalcemia

deficient calcium in the blood

hypokalemia

deficient potassium in the blood

hyponatremia

deficient sodium in the blood

hypoglycemia

deficient sugar in the blood

DI

diabetes insipidus

DM

diabetes mellitus

DKA

diabetic ketoacidosis

endocrin/o

endocrine

adrenomegaly

enlargement (of one or both) of the adrenal glands

acromegaly

enlargement of the extremities (and face due to increased soft tissue, bone, and cartilage; caused by excessive production of the growth hormone by the pituitary gland after puberty)

goiter

enlargement of the thyroid gland. May be caused by autoimmune diseases of the thyroid (Graves disease or Hashimoto thyroiditis), iodine deficiency, or the presence of multiple nodules.

adrenalitis

inflammation of the adrenal glands

thyroiditis

inflammation of the thyroid gland

thyroid gland

largest endocrine gland. It is located anteriorly in the neck below the larynx and comprises bilateral lobes connected by an isthmus. The thyroid gland secretes the hormones triiodothyronine (T3) and thyroxine (T4), which require iodine for their production. Thyroxine is necessary for body cell metabolism.

hypothalamus

located superior to the pituitary gland in the brain. The hypothalamus secretes "releasing" hormones that function to stimulate or inhibit the release of pituitary gland hormones.

pheochromocytoma

tumor of the adrenal medulla, which is usually non-malignant and characterized by hypertension, headaches, palpitations, diaphoresis, chest pain, and abdominal pain. Surgical removal of the tumor is the most common treatment. Though usually curable with early detection, it can be fatal if untreated.

T2DM

type 2 diabetes mellitus (also abbreviated T2D)

thyroid sonography

ultrasound test of the thyroid gland used to help determine whether a thyroid nodule is likely benign or possibly malignant, including whether it is cystic or solid. Also used to help guide a fine needle aspiration (FNA) biopsy.