Endocrinology USMLE Step 1 Vocabulary

Flashcards covering key vocabulary from the Endocrinology USMLE Step 1 lecture notes by Dr. Heba Jihad.

Pharyngeal Pouches

Indentations in the inside of the pharynx of a developing embryo, lined with endoderm.

Pharyngeal Grooves (Clefts)

Indentations in the outside of the pharynx of a developing embryo, lined with ectoderm.

Pharyngeal Arches

Bulges between the pharyngeal pouches and grooves in a developing embryo, composed of mesoderm and neuroectoderm.

Lateral Cervical Cyst (Pharyngeal Cyst)

A cyst found in the lateral part of the neck in a child along the anterior border of the sternomastoid, resulting from a remnant of the 2nd, 3rd, or 4th groove that didn't get filled in.

Foramen Cecum

Normal remnant of the thyroglossal duct.

Lingual Thyroid

Ectopic thyroid tissue that forms within the tongue due to failure of migration during development.

Thyroglossal Cyst (Median Cervical Cyst)

An endodermal-lined cyst in the anterior midline of the neck that moves with swallowing and protrusion of the tongue, due to incomplete fusion of the thyroglossal duct.

DiGeorge Syndrome

A genetic disorder (22q11 deletion) where the 3rd and 4th pharyngeal pouches fail to differentiate into the thymus and parathyroid glands.

Hypophyseal-Portal System

A system of blood vessels that allows delivery of releasing and inhibitory hormones from the hypothalamus directly to the anterior pituitary gland.

Sella Turcica

A bony cavity at the base of the brain where the pituitary gland lies.

Prolactin

Anterior pituitary hormone whose release is negatively regulated by dopamine.

Adenohypophysis

Another name for the Anterior pituitary, originates from the Rathke’s pouch which is an embryonic invagination of the pharyngeal epithelium.

Neurohypophysis

Another name for the Posterior pituitary, derived from neuroectoderm.

Neurophysins

Carrier proteins that transport vasopressin (ADH) and oxytocin from the hypothalamus to the posterior pituitary.

Somatomedin C (IGF-1)

Insulin-like growth factor 1, a growth factor secreted by the liver in response to growth hormone, mediating many of growth hormone's anabolic effects.

Acromegaly

A condition caused by excess growth hormone after closure of the epiphysis, leading to increased thickness of bones.

Gigantism

A condition characterized by a tall stature and long limbs which is due to increase in growth hormone before adolescence and before the union of epiphysis with the shaft.

Laron Dwarfism

A type of dwarfism characterized by high serum levels of growth hormone in the presence of low IGF-1 levels, due to defective growth hormone receptors.

Prolactinoma

A hyperfunctioning pituitary adenoma that secretes prolactin, leading to galactorrhea and hypogonadism. The most common hyperfunctioning pituitary adenoma.

Bitemporal Hemianopsia

Loss of the temporal visual fields in both eyes, caused by compression of the optic chiasm. Can be caused by pituitary tumors.

Sheehan Syndrome

Postpartum necrosis of the anterior pituitary due to hypotension, leading to failure of lactation and other hormone deficiencies.

Pituitary Apoplexy

Acute hemorrhage into the pituitary gland, often presenting with severe headache, bitemporal hemianopsia, and ophthalmoplegia.

Empty Sella Syndrome

Condition where the pituitary gland shrinks or becomes flattened, creating a void in the sella turcica.

Diabetes Insipidus (DI)

A condition characterized by polyuria and polydipsia, resulting from a deficiency in ADH (central DI) or its effect on the kidney (nephrogenic DI).

SIADH (Syndrome of Inappropriate Antidiuretic Hormone Secretion)

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

Conn's Syndrome

Primary hyperaldosteronism: autonomous overproduction of aldosterone despite a high pressure with a low renin activity, resulting in hypertension, hypokalemia, and metabolic alkalosis.

Cushing Syndrome

Hypercortisolism regardless of origin, including chronic glucocorticoid therapy.

Cushing Disease

Hypercortisolism due to an adenoma of the anterior pituitary.

Addison Disease

Another name for Chronic primary adrenal insufficiency, an autoimmune process that destroys the cells of the adrenal glands, resulting in deficiency of glucocorticoids and mineralocorticoids.

Waterhouse-Friderichsen Syndrome

Acute primary adrenal insufficiency due to adrenal hemorrhage associated with septicemia (usually Neisseria meningitidis).

Pheochromocytoma

A tumor of the chromaffin tissue of the adrenal medulla that causes increased production of catecholamines (norepinephrine and epinephrine), resulting in episodic hypertension.

Neuroblastoma

Most common tumor of the adrenal medulla in children, originating from neural crest cells.

Goiter

An enlarged thyroid gland, which can be diffuse or nodular, and present in hypo-, hyper-, and euthyroid states.

Colloid

Material full of thyroglobulin that each thyroid follicle surrounds a cavity with.

Hashimoto's Thyroiditis

Most common cause of hypothyroidism in iodine-sufficient areas, characterized by autoimmune destruction of thyroid cells.

Hurthle Cells

Large, oxyphilic cells with granular cytoplasm that are thyroid follicular epithelial cells that undergo a metaplastic change.

Subacute Thyroiditis (de Quervain's Thyroiditis)

A post-viral inflammatory process of the thyroid gland presenting with fever, neck pain, and a tender goiter.

Cretinism

Severe fetal hypothyroidism due to thyroid dysgenesis.

Grave's Disease

Autoimmune hyperthyroidism caused by autoantibodies (TSI) directed against the TSH receptor, leading to thyroid stimulation and hormone overproduction.

Thyroid Storm

Severe, life-threatening hyperthyroidism that presents with agitation, delirium, fever, diarrhea, coma, and tachyarrhythmia.

Jod-Basedow Phenomenon

Iodine-induced hyperthyroidism that occurs when a patient with iodine deficiency and partially autonomous thyroid tissue is made iodine replete.

Orphan Annie Eye Nuclei

Microscopic features characteristic of papillary cancer of the thyroid gland.

Psammoma Bodies

Concentric calcified structures typically observed in papillary carcinoma of the thyroid.

Chvostek Sign

Contraction of facial muscles elicited by tapping the facial nerve, indicative of hypocalcemia.

Trousseau Sign

Carpal spasm induced by occlusion of the brachial artery with a blood pressure cuff, indicative of hypocalcemia.

Insulinoma

Tumor of pancreatic β cells that secretes insulin, leading to hypoglycemia.

Glucagonoma

Necrolytic migratory erythema (painful pruritic rash), hyperglycemia/diabetes, weight loss, anemia. Dx: Elevated glucagon.

Ghrelin

Stimulates hunger and GH release.

Leptin

Satiety hormone.

Endocannabinoid

Act at cannabinoid receptors in hypothalamus and nucleus accumbens, two key brain areas for the homeostatic and hedonic control of food intake → ↑ appetite.