Adrenal Cortex (continued)

Question 1

What is the primary test for primary vs. secondary hypocortisolism?

Answer 1

ACTH stimulation test:
cortisol levels increase: normal
cortisol levels increase only slightly: hypocortisolism

Definitive test:
Just look at ACTH
Increased = primary hypocortisiolism (Addison’s );
inappropriately low = secondary hypocortisolism

Question 2

Understand this chart.

Answer 2

Understand chart

Question 3

Another name for primary hyperaldosteronism?

Answer 3

Conn’s Syndrome

Question 4

What is Conn’s syndrome caused by?

Answer 4

a small unilateral adenoma on either side (most common);

bilateral adrenal hyperplasia (idiopathic hyperaldosteronism;

or adrenal carcinoma (rare)

Question 5

What is an initial clue for presence of Conn’s syndrome?

Answer 5

detection of hypertension with hypokalema

Question 6

What are some clinical features of primary hyperaldosteronism? (List 5)

Answer 6

• increased whole body sodium, fluid, and circulating blood volume
• infrequent hypernatremia
• increased peripheral vasconstriction and TPR
• BP (from borderline to severe HTN)
• edema (rare) (sodium escape, i.e a major increase in sodium and water retention is prevented by “sodium escape” but mechanism is unclear)
• models left ventricular hypertrophy
• potassium depletion and hypokalemia (causing weakness and fatigue)
• Increased hydrogen ion excretion and new bicarbonate create metabolic alkalosis
• Positive Chvostek or Trousseau’s sign (suggestive of alkalosis leading to low Ca2+)
• Normal cortisol level
• suppressed renin (major feature)

Question 7

What is secondary hyperaldosteronism?

Answer 7

refers to a state in which there is an appropriate increase in aldosterone in response to activation of RAAS

Question 8

What are the 2 types of secondary hyper-aldosteronism?

Answer 8

secondary hyper-aldosteronism with HTN
secondary hyper-aldosteronism with hypotension

Question 9

Major cause of secondary hyperaldosteronism with HTN?

Answer 9

• primary over secretion of renin, secondary to a decrease in renal blood flow and/or pressure( most cases)
• renin secreting tumor (rare)
• renal arterial stenosis, narrowing via atherosclerosis, fibromuscular hyperplasia

Question 10

What are some DDs to remember before diagnosing someone of secondary hyperaldosteronism with HTN?

Answer 10

Hypokalemia in a hypertensive patient not taking diuretics

hypo-secretion of renin with elevated aldosterone that fails to respond to a volume contraction: Conn’s syndrome

Hyper-secretion of renin with elevated aldosterone: renal vascular

Question 11

What are the features of secondary hyper-aldosteronism with hypotension.

Answer 11

• sequestration of blood on the venous side of the systemic circulation (common cause)’
• results in dec. CO and thus dec. BF and pressure to the renal artery
• the following conditions produce:
  CHF
  Constriction of vena cava
  hepatic cirrhosis

Question 12

What are “inborn errors of metabolism”?

Answer 12

When there are single enzyme defects that lead to deficient cortisol secretion and the syndrome called CAH (congenital adrenal hyperplasia)

Question 13

What is the most common of the congenital enzyme deficiencies?

Answer 13

21 β-hydroxylase deficiency

Question 14

What is corticosterone?

Answer 14

a weak glucocorticoid

Question 15

What are the consequences of 21 B-hydroxylase deficiency?

Answer 15

• mineralocorticoid deficiency in 75% cases
• neonates may present with salt-wasting crisis;= hyponatremia, hyperkalemia, and raised plasma renin
• elevated 17 hydroxyprogesterone
• increased androgens, leading to virilization of the female fetus and sexual ambiguity at birth
• males are phenotypically normal at birth but develop precocious pseudopuberty, growth acceleration, premature epiphyeseal plate closure and diminished final height

Question 16

What is treatment for 21 B-hydroxylase defiency?

Answer 16

bringing glucocorticoid and mineralocorticoid back to normal range which also suppresses adrenal androgen secretion; in addition, hydrocortisone to act as feedback inhibition on pituitary

Question 17

What are the consequences of 11 β- hydroxylase deficiency?

Answer 17

clinical features of increased androgens similar to the preceding form including virilization of female fetus

Principal difference with this form is the hypertension produced by 11-deoxycortiocsterone, along with hypokalemia and suprressed renin secretion

Question 18

Treatment for 11 B- hydroxylase deficiency?

Answer 18

For all forms of CAH is gluocorticoids such as hydrocortisone and dexamethasone

Question 19

What are the clinical features of 17 α- hydroxylase deficiency? (excluding testes and ovaries)

Answer 19

zona fasciculata, reticularis: decreased adrenal androgens, decreased cortisol, and increased ACTH.

increased 11-dexoycorticosterone leading to HTN

reduced circulating angiotensin II reduces stimulation os zona glomerulosa and aldosterone secretion

Question 20

Be able to make a chart on the effects of 21 B-OH, 11 B OH, and 17 a-OH on glucocorticoids, ACTH, BP, Mineralocorticoid: Aldosterone Deoxycorticosterone levels , Androgen, Estrogen?

Answer 20

Reproduce chart.