Pathoma- Chapter 15: Adrenal Cortex and Adrenal Medulla

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Secondary/Tertiary Adrenal Insuffieciency What is the metyrapone stimulation test?

-Diagnosis involves measurement of serum electrolytes, morning/random serum cortisol and ACTH (low cortisol, high ACTH in 1° adrenal insufficiency; low cortisol, low ACTH in 2°/3° adrenal insufficiency due to pituitary/hypothalamic disease), and response to ACTH stimulation test. Alternatively, can use metyrapone stimulation test: metyrapone blocks last step of cortisol synthesis (11-deoxycortisol to cortisol). -Normal response is decrease cortisol and compensatory increase ACTH and 11-deoxycortisol. -In 1° adrenal insufficiency, ACTH is increased but 11-deoxycortisol remains decreased after test. -In 2°/3° adrenal insufficiency, both ACTH and 11-deoxycortisol remain decreased after test.

If surgery is not an option to remove the ACTH-secreting pituitary adenoma, what can be done?

-Drugs like ketoconazole or metyrapone can be useful if surgery is not an option

What is the underlying cause of the bilateral adrenal hyperplasia?

-Due to high ACTH levels (lack of negative feedback) acting on the adrenals

What is Chronic Adrenal Insufficiency due to?

-Due to the progressive destruction of the adrenal glands

Pheochromocytoma: Clinical Features

-Episodic HTN -Headaches -Palpitations -Tachycardia -Sweating

Cushing Syndrome: Causes What is the most common cause of Cushing Syndrome?

-Exogenous Corticosteroids

Cushing Syndrome: Causes Which cause is the only one that will result in atrophy of both adrenal glands (very high-yield)?

-Exogenous corticosteroid administration

What are the 4 main causes of Cushing Syndrome (very high-yield!!!)?

-Exogenous corticosteroids -Primary adrenal adenoma, hyperplasia, or carcinoma -ACTH-secreting pituitary adenoma -Paraneoplastic ACTH secretion

21-hydroxylase Deficiency How will the Classic form of the disease present in women?

-Females will have clitoral enlargement (genital ambiguity)

What is the treatment for 11-beta-hydroxylase deficiency?

-Glucocorticoids

What is the treatment for 21-hydroxylase deficiency?

-Glucocorticoids -Mineralocorticoids

What is the treatment for 17-alpha-hydroxylase deficiency?

-Glucocorticoids -Sex steroids

What are the treatments for adrenal insufficiency?

-Glucocorticoids and mineralocorticoids

What is the underlying problem in Cushing Syndrome?

-Have an excess of cortisol

Waterhouse-Friderichsen Syndrome What is it?

-Hemorrhagic necrosis of the adrenal glands

Waterhouse-Friderichsen Syndrome Pathophysiology (very high-yield!!!!)

-Hemorrhagic necrosis of the adrenal glands -This results in acute lack of cortisol- this would then exacerbate the pts. hypotension (that they already have from the N. meningitidis infection and DIC)- on top of that, they get this massive hypotension due to a lack of cortisol

What signs suggest primary adrenal deficiency?

-Hyperpigmentation (high ACTH) and hyperkalemia (low aldosterone)

Chronic Adrenal Insufficiency: Clinical Features

-Hypotension- due lack of cortisol which is necessary to maintain vascular tone -Hyponatremia, hypovalemia, and hyperkalemia- due to lack of aldosterone (so you will have salt- wasting) -Hyperpigmentation -Vomiting and diarrhea- due to a lack of cortisol

Chronic Adrenal Insufficiency: Clinical Features Why will pts. have hyperpigmentation?

-If you don't have any cortisol being produced, you are not going to be able to shut down the production of ACTH via negative-feedback on the anterior pituitary- this will result in excess production of ACTH -ACTH is derived from a molecule called POMC -One of the other derivatives of POMC is alpha-melanocyte stimulating hormone- which stimulate the melanocytes- resulting in hyperpigmentation -Excess ACTH production can also lead to an increase in alpha-MSH

Cushing Syndrome: Clinical Features (Based on Effects of Cortisol) Why will pts. have moon facies, a buffalo hump, and truncal obesity?

-If you have increased gluconeogenesis, you will have high glucose in the blood -The high glucose is going to result in excess insulin being produced by the pancreas -The excess insulin will then result in the storage of fat- in the face, on the back of the neck, and on the trunk

What are the mechanisms by which Secondary Hyperaldosteronism can occur?

-In a young woman, you can get something called fibromuscular dysplasia- which results in thickening of the wall of the renal artery- which would then decrease the blood flow to the kidney- this would activate the JGA -In elderly males, you could get atherosclerosis of the renal artery- which would then decrease the blood flow to the kidney- also activating the JGA

Where does aldosterone work in the nephron?

-In the late distal tubule and the collecting duct

What is hyperaldosteronism?

-Is when you have excess aldosterone

Cushing Syndrome: Clinical Features (Based on Effects of Cortisol) How does cortisol raise the blood sugar?

-It breaks down muscle to provides the AAs necessary for gluconeogenesis

What are the 3 pathways that pregnenolone can enter in the adrenal cortex?

-It can produce mineralocorticoids (aldosterone) (glomerulosa) -It can produce glucocorticoids (cortisol) (fasciculata) -It can also produce sex steroids (reticularis)

What does the high-dose dexamethasone do to ACTH production by an ectopic source?

-It fails to suppress ectopic ACTH production by a small cell lung carcinoma though -Since ACTH production has not changed- there will be no change in cortisol levels

What does the high-dose dexamethasone do to ACTH production by a pituitary adenoma?

-It has the ability to suppress ACTH production by a pituitary adenoma -This will decrease the amount of cortisol being produced

What is a Pheochromocytoma?

-It is a tumor of the chromaffin cells

What is the inheritance pattern of SAME?

-It is autosomal recessive

What is the inheritance pattern of congenital adrenal hyperplasia?

-It is autosomal recessive

What is cholesterol converted to in the adrenal cortex?

-It is converted into pregnenolone (via the enzyme desmolase)

Diagnosis of Cushing Syndrome How does the low-dose dexamethasone test diagnose Cushing syndrome?

-It suppresses cortisol in normal individuals but fails to suppress cortisol in all causes of Cushing syndrome

What does the alpha-intercalated cell do in response to aldosterone?

-It will dump H+ into the lumen of the nephron

Chronic Adrenal Insufficiency What type of cancer LOVES to metastasize to the adrenal glands (very high-yield!!!!)?

-Lung cancer LOVES to metastasize to the adrenal glands -This is very high-yield!!!!!!

What are the genetic syndromes that a pheochromocytoma are associated with?

-MEN 2A and 2B -von Hippel-Lindau disease -Neurofibromatosis type 1

What food can also result in SAME (high-yield!!!!)?

-May also arise with licorice (glycyrrhetinic acid)- which also blocks 11-Beta-HSD2

What is the key thing that kills pts. with MEN 2A and 2B?

-Medullary carcinoma of the thyroid is the key thing that ends up killing patients -One way to avoid the development of the medullary thyroid carcinoma is by removing the thyroid prophylactically

What will the epinephrine be broken down into?

-Metanephrine

Primary Hyperaldosteronism What is the treatment for bilateral adrenal hyperplasia?

-Mineralocorticoid receptor antagonist (e.g., spironolactone or eplerenone) -Adenoma and carcinoma are resected

Zona Glomerulosa What will this portion of the adrenal cortex secrete?

-Mineralocorticoids (such as aldosterone)

What enzyme breaks down metanephrine and normetanephrine into VMA?

-Monoamine oxidase

Cushing Syndrome: Clinical Features (Based on Effects of Cortisol)

-Muscle weakness with thin extremities -Moon facies, buffalo hump, and truncal obesity -Abdominal striae -HTN -Osteoporosis -Immune suppression

Cushing Syndrome: Clinical Features (Based on Effects of Cortisol) As a result of increasing gluconeogenesis by breaking down muscle, what symptoms will pts. have?

-Muscle weakness with thin extremities -This is because you are breaking down the muscle to provide the AAs necessary for gluconeogenesis

VHL Disease Pts. have an increased risk for what (high-yield)?

-Mutation of the VHL tumor suppressor gene -Pts. have an increased risk for hemangioblastoma of the cerebellum, an increased risk for renal cell carcinoma, and an increased risk for a pheochromacytoma

What will the Norepinephrine be broken down into?

-Normetanephrine

How will the adrenal glands appear if the underlying cause of the Cushing Syndrome is due to an adrenal adenoma, carcinoma, or hyperplasia?

-One of the adrenal glands will be large (due to either the adenoma, carcinoma, or hyperplasia) -The large adrenal gland will be secreting excess cortisol -The excess cortisol will go into the blood- and hit the anterior pituitary and shut down the production of ACTH -When ACTH production is shut down, the opposite adrenal gland will actually become atrophied

Pheochromocytoma: Rules of 10s What is a high-yield location for an extra-medullary pheochromocytoma?

-Organ of Zuckerkandl at the inferior mesenteric artery root -Or the bladder wall (very high-yield!!!)

Pheochromocytoma: Adrenalectomy What drug must you give before you remove the tumor (very high-yield!!!!!!)?

-Phenoxybenzamine (irreversible alpha-blocker) followed by Beta-blocker is administered preoperatively to prevent a hypertensive crisis (very high-yield!!!!) -Catecholamines may leak into the bloodstream upon manipulation of the tumor!!!!!

Chronic Adrenal Insufficiency (Addison Disease) What are some other causes of Addison disease?

-Pituitary damage (secondary) -Hypothalamic damage (tertiary)

How does Liddle syndrome present?

-Presents as a child with HTN, hypokalemia, and metabolic alkalosis -With low renin and aldosterone levels (very high-yield!!!)

How will SAME present?

-Presents as a child with HTN, hypokalemia, and metabolic alkalosis -With low renin and aldosterone levels (very high-yield!!!)

21-hydroxylase Deficiency How will the Classic form of the disease present in neonates?

-Presents as hyponatremia and hyperkalemia with life-threatening hypotension (salt-wasting type)

21-hydroxylase Deficiency When does the Non-classic form present?

-Presents later in life with androgen excess (high-yield)

Cushing Syndrome: Causes Which cause is the only one that will result in atrophy of one of the adrenal glands and enlargement of the other (very high-yield)?

-Primary adrenal adenoma, hyperplasia, or carcinoma

What is Conn Syndrome?

-Primary hyperaldosteronism, also known as primary hyperaldosteronism or Conn's syndrome, is excess production of the hormone aldosterone by the adrenal glands resulting in low renin levels.

Primary vs. Secondary Hyperaldosteronism

-Primary is characterized by low renin and no edema (aldosterone escape) -Secondary is characterized by high renin; edema is often present

What is the key gene in MEN 2A and 2B before you remove the thyroid (very high-yield!!!!)?

-RET proto-oncogene

What is the treatment for Cushing Syndrome caused by a primary adrenal adenoma, hyperplasia, or carcinoma?

-Resection of the adenoma/carcinoma or bilateral resection of hyperplasia with hormone replacement

What is the treatment for Cushing Syndrome due to Ectopic ACTH secretion?

-Resection of the ectopic source

Glucocorticoid-remediable aldosteronism (GRA) How can it be treated (high-yield!!!!!)

-Responds to dexamethasone (high-yield???!) -He totally skipped this section in the videos....

So if there is a deficiency in 21-hydroxylase, pregnenolone will be shunted to what pathway?

-Result in the preferential production of sex steroids -So the levels of the sex steroids will increase

Why is spironolactone not effective at treating Liddle Syndrome?

-Spironolactone is a specific pharmacologic antagonist of aldosterone, acting primarily through competitive binding of receptors at the aldosterone-dependent sodium-potassium exchange site in the distal convoluted renal tubule -The underlying pathophysiology of Liddle syndrome is NOT mediated by the actions of aldosterone (in fact, aldosterone levels will be low in Liddle Syndrome); it is mediated by the aberrant expression of the ENaC channels -As a result of this, spironolactone will have no effect in regards to the treatment

What is the treatment for a Pheochromocytoma?

-Surgical Excision (adrenalectomy)

Chronic Adrenal Insufficiency What is the most common cause in the Developing World?

-TB destruction of the adrenal gland

What is the treatment for Cushing Syndrome caused by exogenous glucocorticoids?

-Tapering of steroids- if possible

Cushing Syndrome: Causes What will happen with an ACTH-secreting pituitary adenoma?

-The adenoma in the pituitary is secreting ACTH -This ACTH will hit both of the adrenal glands when it goes into the blood- this overstimulation via excess ACTH will result in both adrenals becoming large -Both of the adrenal glands will become large and produce excess cortisol- which will result in Cushing Syndrome

The Chromaffin cells of the adrenal medulla are the main physiologic source of what (very high-yield!!!)?

-The catecholamines (epinephrine and norepinephrine)

Cushing Syndrome: Causes Exogenous Corticosteroids

-The doctors prescribed exogenous corticosteroids to the pt.- and as a result of those exogenous corticosteroids, the pt. will develop Cushing Syndrome

What is the underlying problem in primary hyperaldosteronism?

-The high aldosterone is due to a primary problem within the adrenal gland

Steroidogenesis in the Adrenal Cortex What happens if you are lacking 17-alpha-hydroxylase?

-The only thing that you are going to produce is excess mineralocorticoids -Need 17-alpha-hydroxylase to produce cortisol and sex steroids

What are the 2 main cell types in the late distal tubule and the collecting duct regions of the nephron?

-The principle cell -The alpha-intercalated cell

What does the principal cell do in response to aldosterone?

-The principle cell will reabsorb Na+ and secrete K+ into the lumen of the nephron

What will be seen in a pt. with hyperaldosteronism?

-The pt. will get hypernatremia- because they are increasing the reabsorption of sodium -They are going to get hypokalemia- because they are dumping potassium -They are going to get a metabolic alkalosis because they are dumping H+ ion

What is the function of renin?

-The renin converts angiotensinogen to angiotensin I

If on a Board exam they give you the classic history of someone who has 21-hydroxylase deficiency but they don't have salt-wasting or hyperkalemia and doesn't have hypovolemia, what should you be thinking about (very high-yield!!!!)?

-They have an 11-Beta-hydroxylase deficiency (very high-yield!!!!!)

On a Board exam, if you have a pt. who gets HTN when they urinate, what should you be thinking about (very high-yield!!!!!)?

-Think about a pheochromocytoma involving the wall of the bladder (very high-yield!!!!!!)

21-hydroxylase Deficiency What does the decrease in aldosterone result in?

-This loss of aldosterone will result in salt-wasting -The function of aldosterone is to reabsorb Na+ and dump K+ -So if you are lacking aldosterone, you are going to lose Na+ (salt-wasting), and you are going to hold onto K+ -So the patients will suffer from hyponatremia and hyperkalemia (due to the salt-wasting) -Furthermore, since water would follow the Na+ that was being reabsorbed, it will no longer come in due to the lack of Na+ reabsorption- this can result in hypovolemia

What are the manifestations of Nelson Syndrome?

-This will result in hyperpigmentation, headaches, and bitemporal hemianopsia

What is the treatment for Cushing Syndrome caused by an ACTH-secreting pituitary adenoma?

-Transsphenoidal resection of pituitary adenoma

Both metanephrine and normetanephrine be broken down into?

-VMA

How is the diagnosis of Cushing Syndrome made?

-Via increased 24-hour urine cortisol levels -Via late-night salivary cortisol level (increased) -Low-dose dexamethasone suppression test

Since both of the adrenal glands will enlarged in the case of an ACTH-secreting pituitary adenoma and Paraneoplastic ACTH secretion- how do you distinguish between the two?

-Via the High-dose dexamethasone suppression test

What is the classic high-yield example of acute adrenal insufficiency (very high-yield!!!!)

-Waterhouse-Friderichsen syndrome

Zona Reticularis What will this portion of the adrenal cortex secrete?

-Weak androgens (e.g., DHEA) (sex steroids)

What is the high-dose dexamethasone test?

-When you give a pt. high-dose dexamethasone (which is a cortisol analog) -It has the ability to suppress ACTH production by a pituitary adenoma -It fails to suppress ectopic ACTH production by a small cell lung carcinoma though

Why will pts. with hyperaldosteronism get HTN?

-When you grab Na+, water is going to follow- which will result in an increase in blood volume- leading to HTN

What is adrenal insufficiency?

-When you have a lack of adrenal hormones

Cushing Syndrome: Causes Why will the adrenal glands become atrophic as a result of exogenous corticosteroid administration?

-When you have exogenous cortisol in the blood- that cortisol will go to the anterior pituitary and shut down the production of ACTH -When you shut down the production of ACTH- this will then result in both adrenal glands becoming small (bilateral adrenal atrophy)

Primary Hyperaldosteronism Why will the renin levels be low (very high-yield!!!!)?

-When you have high aldosterone, you are going to grab sodium and H2O is going to follow- this will increase the blood volume -That high blood volume is then going to go to the kidney- so the kidney is going to see an increase in blood flow -This increased blood flow to the kidney will decrease the production of renin

What is congenital adrenal hyperplasia?

-When you have hyperplasia of both adrenal glands due to a congenital defect in the enzymes necessary for steroidogenesis -Leading to excess sex steroids

What are the signs of 11-Beta-hydroxylase deficiency?

-Will see an androgen excess- leading to clitoral enlargement (genital ambiguity) in females -However, you will have increased levels of deoxycorticosterone

What signs suggest secondary/tertiary adrenal insufficiency?

-Will see no hyperpigmentation (low ACTH) and normal potassium (normal aldosterone)

What will the renin and aldosterone levels be in Liddle Syndrome?

-With low renin and aldosterone levels (very high-yield!!!)

What will the renin and aldosterone levels be in SAME?

-With low renin and aldosterone levels (very high-yield!!!)

Steroidogenesis in the Adrenal Cortex What would be seen with a 11-hydroxylase deficiency?

-Would not be able to produce cortisol -Would also get some shunting towards sex steroid synthesis -However, there would be a little bit of production of the weak mineralocorticoids (DOC)- so you wouldn't see any salt-wasting

What happens when the JGA is activated?

-You are going to then secrete renin

What is the cause of Secondary Hyperaldosteronism due to?

-You get high aldosterone secondary to the fact that you have activate the renin-angiotensin system

Cushing Syndrome: Causes What will happen in paraneoplastic ACTH secretion?

-You have a tumor (the most classic example is a small cell carcinoma of the lung)- the tumor secretes ACTH -That ACTH goes into the blood and acts on both adrenal glands -Both adrenal glands will become large and produce cortisol- which will result in Cushing Syndrome

Pheochromocytoma How will it appear on gross exam (very high-yield!!!!)?

-You will get a brown tumor!!!!!!! -This is because the adrenal medulla, itself, is brown- so a tumor of the adrenal medulla will also be brown

What will the renin levels be in Secondary hyperaldosteronism?

-You will have a high renin level

Primary Hyperaldosteronism What will the serum levels be of aldosterone and renin?

-You will have high aldosterone (hence the name) -Will have a low renin level

What are the 3 layers of the adrenal cortex (high-yield)?

-Zona glomerulosa -Zona fasciculata -Zona reticularis

What is the classic malignancy that results in paraneoplastic ACTh secretion?

-small cell carcinoma of the lung -Also seen in carcinoid tumors

Cushing Syndrome: Clinical Features (Based on Effects of Cortisol) Why will these pts. suffer from immune suppression (high-yield!!!)?

1.) Cortisol inhibits phospholipase A2- this results in the inability to generate arachidonic metabolites- which are essential for inflammation 2.) It inhibits IL-2- an important T-cell growth factor 3.) Inhibits the release of histamine from mast cells- histamine is essential for vasodilation and increased vascular permeability -These mechanisms are very high-yield!!!!!

Waterhouse-Friderichsen Syndrome Gross Example (very high-yield!!!)

-'Sack of blood' adrenal- that classically shows up on exams

Pheochromocytoma: Rules of 10s

-10% bilateral -10% familial (in kids) -10% malignant -10% located outside of the adrenal medulla -10% calcify

What happens in Syndrome of Apparent Mineralocorticoid Excess (SAME)?

-11-Beta hydroxysteroid dehydrogenase 2 (11-Beta-HSD2) deficiency allows cortisol to activate renal aldosterone receptors

What is the role of 11-Beta-HSD2?

-11-Beta-HSD2 converts cortisol to cortisone in mineralocorticoid-responsive cells (like the ones in the zona glomerulosa) -This prevents cortisol from acting on the Mineralocorticoid receptors- which it can do at high enough concentrations!!!!

Steroidogenesis in the Adrenal Cortex What do you need in order to produce the next level of mineralocorticoids (aldosterone)?

-11-hydroxylase

Steroidogenesis in the Adrenal Cortex What enzyme do you need in order for pregnenolone to enter into the pathway to develop cortisol and sex steroids?

-17-alpha-hydroxylase

Steroidogenesis in the Adrenal Cortex In which enzyme deficiencies will the levels of 17-hydroxyprogesterone be decreased?

-17-alpha-hydroxylase deficiency

Steroidogenesis in the Adrenal Cortex What enzyme do you need to produce weak mineralocorticoids (11-deoxycorticosterone (DOC))?

-21-hydroxylase

What enzyme do you need to produce mineralocorticoids and cortisol from pregnenolone?

-21-hydroxylase

Steroidogenesis in the Adrenal Cortex What enzymes do you need in order to produce Cortisol?

-21-hydroxylase -11-hydroxylase

Congenital Adrenal Hyperplasia What is the most common deficiency seen?

-21-hydroxylase deficiency

Steroidogenesis in the Adrenal Cortex In which enzyme deficiencies will the levels of 17-hydroxyprogesterone be increased?

-21-hydroxylase deficiency -11-alpha-hydroxylase deficiency

What is the most common cause of primary hyperaldosteronism?

-A benign tumor (adenoma) of the adrenal gland

What test is used to distinguish between secondary and tertiary adrenal insufficiency?

-ACTH response with CRH stimulation test suggests hypothalamic (tertiary) disease

What happens in Glucocorticoid-remediable aldosteronism (GRA) and what is its inheritance pattern?

-Aberrant expression of aldosterone synthase in the zona fasciculata due to an autosomal dominant genetic mutation- leading to familial hyperaldosteronism -This makes the aldosterone synthase fall under the control of ACTH instead of angiotensin II -So with release of ACTH- aldosterone synthase now goes to work- producing more aldosterone -It is autosomal dominant -Read the attached image!!!

Other causes of Acute Adrenal Insufficiency

-Abrupt withdrawal of glucocorticoids -Treatment of Cushing Syndrome

What are the 2 forms of adrenal insufficiency?

-Acute and Chronic forms

Cushing Syndrome: Causes What kind of adrenal problem can lead to Cushing Syndrome?

-Adrenal adenoma -Adrenal hyperplasia -Adrenal carcinoma -All 3 of these things can produce cortisol

What are the two portions of the adrenal gland?

-Adrenal cortex -Adrenal medulla

What hormones will be decreased with 21-hydroxylase deficiency?

-Aldosterone -Cortisol

Zona Glomerulosa What is the function of aldosterone?

-Aldosterone is important for salt maintenance within the body

Glucocorticoid-remediable aldosteronism (GRA) What will the aldosterone and renin levels be?

-Aldosterone will be high, and renin will be low

Steroidogenesis in the Adrenal Cortex 17-alpha-hydroxylase Deficiency What are the signs seen in males?

-Ambiguous genitalia with undescended testes (males)

What is the treatment for Liddle Syndrome?

-Amiloride and triamterene- two K+-sparing diuretics that block the tubular Na+-channels

21-hydroxylase Deficiency How will the Non-classic form present in females?

-Androgen excess leads to hirsutism with menstrual irregularities in females

21-hydroxylase Deficiency How will the Non-classic form present in males?

-Androgen excess leads to precocious puberty in males

What is the function of Angiotensin II?

-Angiotensin II goes to the adrenal gland and causes the release of aldosterone -So you will have high aldosterone levels because of the fact that you have activated the RAAS

What enzyme converts Angiotensin I to Angiotensin II?

-Angiotensin-Converting Enzyme

Glucocorticoid-remediable aldosteronism (GRA) How will it classically present?

-As a child with HTN and hypokalemia -Aldosterone will be high, and renin will be low

Neurofibromatosis Type 1

-Associated with an increased risk for Pheochromocytoma

Chronic Adrenal Insufficiency What is the most common cause in the West?

-Autoimmune destruction of the adrenal gland

What are the 3 major causes of Chronic Adrenal Insufficiency (very high-yield!!!)?

-Autoimmune destruction of the adrenal gland -TB destruction of the adrenal gland -Metastatic carcinoma from the lung to the adrenal gland

What is the underlying cause of the adrenal hyperplasia in all 3 of the enzyme deficiencies?

-Because in all 3 of the enzyme deficiencies- cortisol levels will be low- leading to an increase inACTH stimulation- resulting in adrenal hyperplasia

Why is cortisol necessary for life (very high-yield!!!!)?

-Because it helps to maintain vascular tone- via upregulation of Alpha-1 receptors on arterioles -Excess cortisol will result in an increase in Alpha-1 receptors- which will then increase the effect of norepinephrine of the arterioles- giving the patients HTN

What is Nelson Syndrome?

-Bilateral adrenalectomy in refractory cases of Cushing disease can lead to enlargement of pituitary adenoma -This will result in hyperpigmentation, headaches, and bitemporal hemianopsia

Cushing Syndrome: Causes What will happen to the adrenal glands as a result of exogenous corticosteroid administration (high-yield!!!)?

-Both adrenal glands will actually become atrophic

How do we screen for Congenital Adrenal Hyperplasia (high-yield)?

-By checking the serum for levels of 17-hydroxyprogesterone

Primary Hyperaldosteronism What imaging modality is useful for determining the etiology?

-CT

What does the adrenal medulla secrete?

-Catecholamines- such as epinephrine and norepinephrine

The adrenal cortex secretes hormones derived from what precursor molecule?

-Cholesterol

What molecule is the starting point for steroidogenesis in the adrenal cortex?

-Cholesterol

All of the hormones produced by the adrenal cortex are derived from what precursor molecule (high-yield)?

-Cholesterol -The adrenal gland has a very distinct yellow color- which is due to the fact that it is loaded with cholesterol- which will go on to make all of the hormones secreted by the adrenal cortex

The adrenal medulla is composed of what kind of cells (very high-yield)?

-Chromaffin cells

Chronic Adrenal Insufficiency: Clinical Features Where will the hyperpigmentation classically be seen?

-Classically arises in the oral mucosa but also be present on the skin

Waterhouse-Friderichsen Syndrome Is due to what pathogen?

-Classically due to sepsis and DIC in young children with a Neisseria meningitidis infection

Glucocorticoid-remediable aldosteronism (GRA) How can the diagnosis be confirmed?

-Confirmed with genetic testing

Zona Fasciculata What will this portion of the adrenal cortex secrete?

-Cortisol

Cushing Syndrome: Clinical Features (Based on Effects of Cortisol) What is the cause of the abdominal striae?

-Cortisol impairs the synthesis of collagen -So when you have weak collage, the blood vessels can rupture very easily- so you will get these striae on the abdomen which basically represent ruptured blood vessels

21-hydroxylase Deficiency What does the decrease in cortisol result in?

-Cortisol is necessary for life because it maintains vascular tone- so lack of cortisol can lead to life-threatening hypotension -Also, decreased cortisol levels will result in decreased inhibitory feedback on the anterior pituitary- leading to an excess production of ACTH -The excess ACTH will get into the blood- acting on both adrenal glands and causing them to becoming large (why we call it congenital adrenal hyperplasia)

Cushing Syndrome: Clinical Features (Based on Effects of Cortisol) Why can the pts. develop HTN (very high-yield!!!)?

-Cortisol upregulates alpha-1 receptors on the arterioles- which then increases the effect of norepinephrine on the arterioles -At very high levels, cortisol cross-reacts with mineralocorticoid receptors (aldosterone is not increased)

Other causes of Primary Hyperaldosteronism

-Could also be due to sporadic hyperplasia or a carcinoma of the adrenal gland- which are less common causes

Steroidogenesis in the Adrenal Cortex 17-alpha-hydroxylase Deficiency What are the signs seen in females?

-Decreased androgens lead to primary amenorrhea and lack of pubic hair (females)

What are the signs of 17-alpha-hydroxylase deficiency?

-Decreased cortisol and androgen levels -Weak mineralocorticoids (DOC) are increased leading to HTN- with mild hypokalemia -Renin and aldosterone are low (?????)

What is Liddle Syndrome and what is its inheritance pattern?

-Decreased degradation of sodium channels in collecting tubules due to a genetic mutation -It is autosomal dominant

What are the signs of 11-Beta-hydroxylase deficiency?

-Deoxycorticosterone (DOC) leads to HTN (sodium retention) with mild hypokalemia -Renin and aldosterone are low -Clitoral enlargement is seen in females (genital ambiguity)- due to shunting towards androgen production

The Chromaffin cells are derived from what (very high-yield!!!)?

-Derived from the neural crest!!!!!

Pheochromocytoma How is it diagnosed (very high-yield!!!!)?

-Diagnosed by increased serum metanephrines and increased 24-hour urine metanephrines and VMA

How is SAME diagnosed?

-Diagnosed by low urinary free cortisone (high-yield- due to deficiency in the activity of 11-Beta-HSD2) and genetic testing!!!

How is Liddle syndrome diagnosed?

-Diagnosed via genetic testing


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