Adrenal Gland (hypo)

Question 1

What is the steroid precursor ?

Answer 1

Cholesterol

Question 2

Examples of corticosteroids

Answer 2

Mineralocorticoids (Aldosterone)
Glucocorticoids (Cortisol)
Sex steroids (Androgens, oestrogens)

Question 3

Which part of the adrenal cortex secretes aldosterone?

Answer 3

Zona glomerulosa

Question 4

Which part of the adrenal cortex secretes cortisol?

Answer 4

Zona fasiculata

Question 5

Which part of the adrenal cortex secretes androgens and oestrogens?

Answer 5

Zona fasiculata and reticularis

Question 6

What is the overall effect of aldosterone?

Answer 6

Reduces potassium (Potassium excretion)
Regulates sodium (sodium reabsorption)
Maintains blood pressure

Question 7

Effects of angiotensin II on the adrenals

Answer 7

3-hydroxysteroid dehydrogenase
21-hydroxylase
11-hydroxylase
18-hydroxylase

Question 8

Effects of ACTH on the adrenals

Answer 8

Side Chain Cleavage
3 Hydroxysteroid dehydrogenase
21 hydroxylase
11 hydroxylase
17 hydroxylase

Question 9

Steroid biosynthetic pathway

Answer 9

Question 10

What type of rhythm is exhibited by cortisol secretion?

Answer 10

Diurnal rhythm

Question 11

What is Addison’s

Answer 11

Primary adrenocortical failure

Question 12

What is the main cause of Addison’s disease in the UK?

Answer 12

(Autoimmune induced destruction of the adrenal cortex)
Atrophy of the adrenal glands.

Question 13

What is the main cause of Addison’s disease worldwide?

Answer 13

Tuberculosis

Question 14

What are the clinical features of Addison’s disease?

Answer 14

Question 15

Why do we see hyperpigmentation in patients with Addison’s disaese?

Answer 15

alpha-MSH (Melanocortin-stimulating hormone)

Question 16

Which congenital condition is associated with adrenocortical failure?

Answer 16

Congenital adrenal hyperplasia

Question 17

What are the consequences of adrenocortical failure?

Answer 17

1) Fall in blood pressure (hypotension)
2) Loss of salt in the urine (hyponatremia)
3) Increased plasma potassium (hyperkalaemia)
4) Fall in glucose due to glucocorticoid deficiency (Hypoglycaemia)
5) High ACTH resulting in increased pigmentation

Question 18

Which adrenal hormones are predominantly insufficient in primary adrenocortical failure?

Answer 18

Aldosterone and cortisol

Question 19

Where is pro-opio melanocortin synthesised?

Answer 19

Synthesised within the pituitary gland.

Question 20

What clinical investigations are conducted for a patient suspected with Addison’s?

Answer 20

9am cortisol = low
ACTH = High
Short synACTHen test to measure the cortisol response (low response)

Question 21

What is a synACThen test?

Answer 21

ACTH is administered to patients through intramuscular injections (250ug), and the cortisol response is measured (should stay low)

Question 22

What pharmacological treatment is available for primary adrenocortical failure?

Answer 22

Fludrocortisone 50-100mg daily

Hydrocortisone thrice daily (10, 5, 2.5mg)
Prednisolone once daily (3mg)

Question 23

What pharmacodynamic effect does fluorine have in fludrocortisone?
what receptors does fludrocortisone act on?

Answer 23

Fluorine does not exist in natural steroids, so its presence slows metabolism substantially.
Has a longer half life (3.5h and effects seen for 18h)
Binds to both mineralocorticoid and glucocorticoid receptors.

Question 24

Why does oral hydrocortisone require more than once daly administration?

Answer 24

Short half-life

Question 25

What are the pharmacological advantages of prednisolone (1-2 dehydro-hydrocortisone) compared to cortisol?

Answer 25

Longer half life More potent that cortisol Higher binding affinity

Question 26

What three doses are available for prednisolone? Is it enteric coated?

Answer 26

1mg 2.5mg 5mg NOT enteric coated which slows absorption

Question 27

What is the recommended dose for prednisolone replacement therapy? What hydrocortisone dose is this equivalent to?

Answer 27

2mg-4mg once daily This would be an equivalent dose of 15-25mg hydrocortisone daily

Question 28

What is the most common enzyme deficiency in congenital adrenal hyperplasia?

Answer 28

21-hydroxylase deficiency

Question 29

Which adrenal hormones are deficient in a congenital adrenal hyperplasia complete 21-hydroxylase deficiency?

Answer 29

Aldosterone and cortisol

Question 30

Which hormones are increased in congenital adrenal hyperplasia with complete 21-hydroxylase deficiency?

Answer 30

Sex steroids (androgens such as testosterone, oestrogen)

Question 31

How long can a patient survive with diagnosed complete 21-hydroxylase deficiency?

Answer 31

Less than 24 hours

Question 32

What is the age of presentation of complete 21-hydroxylase deficiency? How does foetus get steroids in utero? Physical features of this deficiency?

Answer 32

As a neonate with a salt losing Addisonian crisis Before before (while in utero) foetus gets steroids across placenta. Girls will be born with ambiguous genitalia due to excess testosterone production.

Question 33

Which hormone are deficient in a partial 21-hydroxylase deficiency?

Answer 33

cortisol and aldosterone

Question 34

Which hormones are in excess in a partial 21-hydroxylase deficiency?

Answer 34

Testosterone

Question 35

What is the main difference between a partial 21-hydroxylase deficiency and complete deficiency?

Answer 35

Aldosterone and cortisol is still produced in smaller quantities Partial can present at any age

Question 36

What are the main associated symptoms of partial 21-hydroxylase deficiency that present later in life in girls and in boys?

Answer 36

Main problem in later life is hirsutism and virilisation in girls and precocious puberty in boys due to adrenal testosterone

Question 37

Which aldosterone precursor behaves analogous to aldosterone?

Answer 37

11 deoxycorticosterone

Question 38

In excess, what effects can be caused by 11 deoxycorticosterone?

Answer 38

hypertension and hypokalaemia

Question 39

Which hormones are in excess in a 11-hydroxylase deficiency and what problems does this cause?

Answer 39

Sex steroids Testosterone 11-deoxycorticosterone Virilisation, hypertension and low K

Question 40

Which hormones are deficient in a 17-hydroxylase deficiency?

Answer 40

Sex steroids, Cortisol

Question 41

Which hormones are in excess in a 17-hydroxylase deficiency?

Answer 41

Aldosterone | 11-deoxycorticosterone

Question 42

What are the associated problems with a 17-hydroxylase deficiency?

Answer 42

Hypertension Hypokaleia Sex steroid deficiency glucocorticoid deficiency (hypoglycaemia)