Emre Jumbo

Vocabulary flashcards for reviewing endocrine system lecture notes.

Hypothalamus

Receives signals from upper cortical inputs, autonomic function, and environmental signals; located below the 3rd ventricle, above the optic chiasm.

Adenohypophyses

Arises from Rathke’s pouch from oral cavity, includes Somatotrophs, lactotrophs, thyrotropes, gonadotrophs, and corticotropes in pars distalis.

Neurohypophysis

Arises from neural ectoderm.

ADH

Kidney tubules, water reabsorption

Oxytocin

Uterine muscles and mammary glands contraction

Superior hypophyseal artery

From anterior cerebral artery supplies anterior lobe. Parvicellular area to adeno- hypophysis>Portal circulation

Inferior hypophyseal artery

From internal carotid supplies Neurohypophysis

Growth hormone

Secreted by pituitary, increases lipolysis, protein synthesis, antagonist of insulin action (Insulin resistance). Phosphate, water and Na retention.

Deficiency of Growth hormone

Leads to Obesity, skeletal fragility, decreased muscle mass, and bone density.

Somatostatins

Inhibits GH, TSH, ACTH, insulin, gastrin.

Pit-1, and Prop-1

Transcription factors are important for differentiation of adenohypophysis hormones. Mutation of these genes cause multiple anterior lobe hormone deficiency.

Prolactin

Affecting mammary glands to produce milk. Dopamine inhibits prolactin secretion.

Hyperprolactinemia

Due to pregnancy, renal failure, oestrogens, liver failure, adenoma (prolactinoma), chest wall (Herpes Zoster), sleep, stress, nipple stimulation, hypothyroidism, sarcoidosis, and stalk effect.

TRH

Stimulates pituitary for secretion of TSH>Thyroid glands>T3-T4, and Iodine reuptake. Inhibited by stress and somatostatin.

ACTH

Produced from proopiomelanocortin, affect Cortisol in zona fasciculata, and androgen synthesis in zona reticularis in adrenal cortex, peak in the morning.

GnRH

Released from hypothalamus stimulates pituitary glands to secrete LH, and FSH.

LH affecting Leydig cells

Testosterone

FSH affects Sertoli cells

Inhibin

Kallman syndrome

Bulbus olfactorius agenesis, no GnRH synthesis. Anosmia, Cleft palate, and hypogonadotropic hypogonadism is present.

LH surge

Ovulation, around 14th day of cycle, oestrogen increases the LH by positive feedback causing fluid production within follicle, protrusion against ovary wall>Release the oocyte into uterine.

Central Diabetes Insipidus

Decreased release of ADH (Vasopressin), resulting in polyuria (Over 3 L/day in adults, 2 L/day in children).

Nephrogenic Diabetes Insipidus

Due to defect in aquaporin-2. Amphotericin-B, aminoglycoside, Lithium, hypercalcemia, acute tubular necrosis, polycystic kidney disease can cause.

V1 receptors

Constriction, increased systemic vascular resistance.

V2 receptors

Fluid reabsorption in kidneys.

Water deprivation test

Body weight, urine volume, osmolality and Na levels are checked. Water intake stopped for 4-8 hours.

Wolfram syndrome

DIDMOAD, Diabetes Insipidus, Diabetes Mellitus, Optical atrophy, and Deafness. Caused by WFS1 gene mutation.

Langerhans’s cell histiocytosis

Abnormal proliferation of Langerhans’s cells in bones, skin, lungs, liver, and pituitary gland. In biopsy>Birbeck granules are pathognomonic.

Bitemporal heteronymous hemianopsia

Visual field abnormalities due to pressure on optic chiasm

Hypopituitarism

Diminished secretion of one or more pituitary hormones. GH>LH/FSH>TSH>ACTH>PRL are affected in order.

Sheehan syndrome

Characterized by post-partum hypopituitarism, due to ischemic necrosis (Massive haemorrhage).

Pituitary apoplexy

Spontaneous haemorrhagic infarction of pituitary tumour. Fulminant, life-threatening. Severe headache, visual impairment, ophthalmoplegias, meningismus, and altered consciousness.

Lymphocytic Hypophysitis

Diffuse infiltration, hyperprolactinemia is seen. Seen in post-partum period.

Central adrenal insufficiency

Blood is taken in the morning. If serum cortisol level is lower than 15 μg/dl>Low dose metyrapone test.

MEN1, MEN4, Carney complex

Familial hypophysis tumour syndromes

McCune Albright syndrome

Café au-lait spots, bone fibrotic dysplasia, autonomous endocrine hyperfunction (Acromegaly, puberty precocious, hyperthyroidism, Cushing).

Prolactinoma

Most common adenoma of hypophysis. Elevated serum PRL, low oestrogen and testosterone.

Macroprolactinoma

Big molecules of prolactin (Anti-PRL antibodies) do not cross the capillary fenestrate, not show any clinical effect but high serum level.

GH-secreting pituitary adenomas

Acromegaly (Local overgrowth of bone) in adults, and gigantism in children are present.

ACTH-secreting pituitary adenoma (Cushing’s disease)

Most common cause of endogenous hypercortisolism (Mostly microadenoma).

Nelsson syndrome

After bilateral total adrenalectomy, suppressive effect of cortisol no longer presents, ACTH secretion increases.

Euchoidism

Arm span is 5 cm longer than height, and upper/lower segment ratio is lower than 1.

Pemberton sign

Thyromegaly can cause superior mediastinal compression. Elevation of both arms cause red face, the veins fill.

Chvostek sign

Tapping the skin over facial nerve about 2 cm anterior to external auditory meatus, ipsilateral contraction occurs in hypocalcaemia.

Trousseau’s sign

Carpopedal spasm induced by ischemia>Flexion of wrist with hyperextension of the fingers while inflating the pressure cuff.

Hirsutism

Male type hairs in women. Degree is calculated by Ferryman-Gallwey scale.

Craniopharyngioma

Most common primary tumour in hypothalamus. Headache, visual field loss are present. In direct graphy>Suprasellar cystic calcified mass.

Refetoff’s syndrome

Thyroid hormone resistance, THRB mutation. Elevated TSH, T3-T4. Causes hypothyroidism symptoms.

Radioactive iodine uptake

Low in thyroiditis, thyrotoxicosis, over iodine supply. Uptake is high in Graves, toxic nodule, toxic goitre, TSHoma.

Myxoedema coma

Overt hypothyroid patient predisposed to cold, trauma, infection, and CNS depressants, causing aggravation of the symptoms. Coma, hypothermia, hypotension, hypoventilation, hyponatremia.

Thyrotoxicosis

Overactive thyroid hormones. Hyperthyroidism (Radioactive iodine uptake, in Graves), or thyroiditis (No uptake, in amiodarone, Lithium), can cause.

Graves’s disease

Most common cause of thyrotoxicosis, familial, TSI antibody are present. Thyrotoxicosis, diffuse goitre, ophthalmopathy, and dermopathy are present.

Grade of palpable thyroid

Grade 0>No palpable, Grade Ia>Palpable, no visible, Ib>Visible on extension. Grade II>Visible on normal position, Grade III>Visible from far away.

Thyroid crisis

Patients with hyperthyroidism encounter with severe infection, surgery, radioactive Iodine, myocardial infarction>Symptoms are worsened. Hyperthermia, tachycardia, vomiting, delirium.

EU-TIRADS

EU-TIRADS 1>Benign cyst. Level 5>Non-oval, irregular, calcified, marked hypo-echogenicity. High risk.

Papillary thyroid cancer

Mostly seen histologic type. Radiation is common cause (BRAF mutation). Psammoma body, and Ophan Annie nucleus in microscopy.

Follicular thyroid cancer

Iodine deficiency, vascular invasion. Molecular test should be done, not biopsy. Haematogenous spread.

Medullary thyroid cancer

Mostly sporadic, but RET mutation can be seen. MEN2A-2B syndromes may present. Originated from parafollicular C cells (NET), do not cause hyperthyroidism. Only thyroidectomy.

Anaplastic thyroid cancer

Worst prognosis, old age, solid tumour, local invasion. Treatment is total thyroidectomy, and lymphatic dissection, radioactive iodine, T4 suppression.

Toxic adenoma

Low TSH, high T3-T4. Hyperactive nodule and suppressed peripheral tissue in scintigraphy.

Toxic multi-nodular Goitre

More in old female, low TSH, high T3-T4. Heterogeneous, and hot nodule in scintigraphy.

Riedel’s thyroiditis

Chronic, sclerosing type. Asymmetric, hard thyroid, IgG4 related.

MEN

Presence of tumours involving 2 or more endocrine gland. Autosomal dominant predisposition.

Berry sign

Inability to feel carotid pulse due to displacement laterally by goitre.

Sistrunk procedure

Surgical removal of thyroglossal cyst and hyoid bone.

Bethesda classification

Type I>Undiagnostic. Type II>Benign, hyperplastic, Type III>Atypia of undetermined origin. Type IV>Follicular neoplasm. Type V>Suspicious for malignancy. Type VI>Malign.

Type I DM

Auto-immune or idiopathic B-cell destruction in pancreas, absolute insulin deficiency.

Type II DM

Insulin resistance with partial insulin deficiency.

Metabolic syndrome

Central obesity, triglyceride>150 mg/dl, HDL<50 mg/dl in women, <40 in men, Hypertension, and fasting blood glucose over 100 mg/dl.

OGTT test indications

Obesity, impaired fasting glucose, family history, gestational diabetes (24-28 weeks), hypertension, dyslipidaemia, PCOS, CVD, and erectile dysfunction.

Diabetic ketoacidosis

Characterized by hyperglycaemia (Over 250 mg/dl), acidosis, and ketonemia, HCO3<15 mEq/L.

Hyperglycaemic hyperosmolar state

Increase gluconeogenesis in liver, dehydration due to osmotic diuresis, and increased serum osmolality (>320 mOsm/Kg). Blood glucose is over 600 mg/dl.

Whipple’s triad

In patient without DM, hypoglycaemic symptoms are present, plasma venous glucose level<55 mg/dl, and back to normal with glucose intake.

Anorexigenic mediators

CART (Cocaine and amphetamine related transcript), Leptin, a- MSH (Alpha melanocyte stimulating hormone), GLP-1, and Serotonin.

Orexigenic mediators

Neuropeptide Y, MCH, AgRP, orexin, Ghrelin, and endocannabinoids.

Hereditary cancer syndrome

Early onset, multiple cancers, bilateral disease, family history.

Li-Fraumeni syndrome

Soft tissue carcinoma, osteosarcoma, adrenocortical, breast, and CNS are affected.

Familial hypocalciuric hypercalcemia

Autosomal dominant. CaSR gene mutation>Ca is normal but cannot sense>Increase in PTH>Abnormal reabsorption of Ca in Henle’s loop.

Acute hypocalcaemia emergencies

Grand Mal epilepsy, Laryngeal spasm, and Cardiac arrhythmias.

Osteomalacia

Mineralisation defect due to Vit-D deficiency, after epiphyseal closure

Endocrine hypertension causes

Reno-vascular diseases, primary aldosteronism (Most common), obstructive sleep apnoea, pheochromocytoma, Cushing’s, Hypo/Hyperthyroidism, aorta coarctation, primary hyperparathyroidism, hypercalcemia, hypoglycaemia, CAH, and acromegaly.

Liddle syndrome

Autosomal dominant, ENaC channel over-activation in distal tubules, increase in Na reabsorption, and K secretion.

Pheochromocytoma

Neuroendocrine tumours secreting catecholamine in chromaffin cells from adrenal medulla. Triad is headache, sweating, tachycardia with hypertension (Paroxysmal).

Pheochromocytoma diagnosis

Hyper-adrenergic seizure, young, resistant HT, familial syndromes, adrenal mass, and HT in surgery>In 24 hours urine metanephrine elevation is diagnostic.

Adrenal Incidentaloma

High Plasma metanephrine level, urinary cortisol level high aldosterone, and over 4 cm>Unilateral adrenalectomy.

Cold, and hypoactive nodule

Highly malignant

Parathyroid scintigraphy

Indicated in parathyroid adenoma localization. 99mTc-sestamibi is taken by mitochondria. In early phase, both thyroid and parathyroid, in late phase>Only parathyroid adenoma seen.

Addison’s disease

Adrenal glands are damaged, both aldosterone, and cortisol is low.s

Cholesterol is turned into pregnenolone

By StAR enzyme

T4a

Extension to chest wall.

T4b

Ulceration, ipsilateral.(Tumour staging)

T4c

Both T4a, and T4c.(Tumour staging)

T4d

Inflammatory carcinoma.(Tumour staging)

Lumpectomy

Excision of the mass

Neoadjuvant therapy

For reducing the mass, and evaluation of sensitivity of tumour before the surgery.

Fibrocystic changes

Pre-menstrual cyclic engorgement, pain, tenderness, green nipple discharge. Dense, and nodular breast tissue on palpation, multiple cysts may present. 40-50 years of age, not a pre-malign lesion.

Fibroadenoma

Most common benign tumour of breast in young women, rubbery, well-circumscribed, mobile. Growth during pregnancy, and oestrogen therapy, regress during menopause.

Mondor disease

Thrombophlebitis involving superficial veins of anterior chest wall.

Pathological Nipple discharge

Spontaneous, unilateral, bloody, or serous. Intra-ductal papilloma, duct-ectasia, fibrocystic changes, and cancer.

BIRADS

level 0>Negative finding, annual screening. Level 1,2>Benign. Level 3>Likely benign, Level 4-5>Malign, biopsy indication.