15.10 Adrenal Cortex

Question 1

What is generated in the glomerulosa?

Answer 1

Mineralocorticoids - aldosterone

Question 2

What is generated in the fasciculata?

Answer 2

Glucocorticoids - cortisol

Question 3

What is generated in the reticular?

Answer 3

Sex Steroids

Question 4

Cushing Syndrome

Answer 4

Excess cortisol

Question 5

What are the features of Cushing syndrome?

Answer 5

• Moon facies
• Buffalo hump
• Truncal obesity
• Muscle weakness
• HTN
• Osteoporosis
• Immune suppression

Question 6

How does cortisol cause HTN?

Answer 6

Upregulation of alpha-1 receptors

Question 7

How does cortisol cause immunosuppression?

Answer 7

• Inhibition of IL-2
• Inhibition of phospholipase A2
• Inhibits histamine

Question 8

What are the causes of Cushing syndrome?

Answer 8

• Exogenous corticosteroids
• Adrenal adenoma, hyperplasia or carcinoma
• ACTH-secreting pituitary adenoma
• Paraneoplastic ACTH secretion

Question 9

What tumor can cause paraneoplastic ACTH secretion?

Answer 9

SCC of the lung

Question 10

What cause of Cushing syndrome will cause bilateral adrenal atrophy?

Answer 10

Exogenous corticosteroids

Question 11

What will respond with decreased ACTH in response to dextromethasone?

Answer 11

Pituitary adenoma - SCC of the lung will NOT

Question 12

Hyperaldosteronism

Answer 12

Excess aldosterone

Question 13

What are the features of hyperaldosteronism?

Answer 13

• Hypernatremia
• Hypokalemia
• Metabolic Alkalosis
• HTN

Question 14

What is the most common cause of primary hyperaldosteronism?

Answer 14

Adrenal Adenoma

Question 15

What are the lab findings for renin and aldosterone in primary hyperaldosteronism?

Answer 15

• High aldosterone

- Low renin

Question 16

What are the causes of secondary hyperaldosteronism?

Answer 16

Activation of the RAA system leading to high aldosterone with high renin - often due to renovascular HTN

Question 17

Congenital Adrenal Hyperplasia

Answer 17

Excess sex steroids with hyperplasia of both adrenal glands

Question 18

What is the most common cause of congenital adrenal hyperplasia?

Answer 18

21-hydroxylase deficiency

Question 19

Why is there hyperplasia in the adrenals in congenital adrenal hyperplasia?

Answer 19

There is a deficiency of cortisol as all steroid genesis is shunted towards sex steroids - leads to increased ACTH and adrenal hyperplasia

Question 20

What is 21-hydroxylase required for?

Answer 20

Mineralcorticoid and cortisol production

Question 21

What are the clinical features of congenital adrenal hyperplasia?

Answer 21

• Hyponatremia
• Hyperkalemia
• Hypovolemia
• Hypotension that is life threatening

Question 22

What happens with 11-hydroxylase deficiency?

Answer 22

• No cortisol
• Only weak mineralocorticoid production so no salt wasting
• Most is shunted to sex steroid production

Question 23

What is required for pregnenolone to enter into the synthesis pathway and become cortisol or sex steroids?

Answer 23

17-hydroxylase - if deficient there will be excess mineralocorticoids

Question 24

Adrenal Insufficiency

Answer 24

Lack of adrenal hormones

Question 25

Waterhouse-Friderichsen Syndrome

Answer 25

Often in a young child with N. meningitides who develops DIC with bilateral adrenal atrophy - “sack of blood”

Question 26

Chronic Adrenal Insufficiency

Answer 26

Slow destruction of the adrenal glands

Question 27

What are some of the causes of chronic adrenal insufficiency?

Answer 27

• Autoimmune (common in West)
• TB (common in 3rd world)
• Metastatic Carcinoma

Question 28

What cancer often metastasizes to the adrenal glands?

Answer 28

Lung cancer