Lecture 17 - steroid abnormalities

Question 1

Glucocorticoid deficiencey (cortisol)

what is a sign of skin?

Answer 1

CRH –> acth –> cortisol
-Cortisol will inhibit adh secretion (adh is involved in the absorption of water from kidney)

Hyponatremia (get more ADH as cortisol is decreased, so get more water absorption, this dilutes the sodium)
Hypoglycaemia (cortisol stimualtes gluconeogensis in liver to produce glucose, have less cortisol so less of this)
Hypotension (cortisol has effects on the blood vessels)

-skin goes brown –> increase pigmentation
Dark skin - primary problem with acth

Question 2

Mineral corticoid deficiencey (aldosterone)

Answer 2

Aldosterone - stimulates reabsorption of sodium, secretion of K+ and H+
-Regulates ECF volume by regulating sodium (brings water in with it)

Hyponatremia
Hyperkalemia
Metabolic acidosis

Question 3

Crushings syndrome

Answer 3

• Excess of cortisol
• can cause obesity, hair on face, facial plethora (redness) decreases growth
• Excess cortisol - can bind to mineralcoritcoid receptor (aldosterone usually binds here) and this can cause increase in sodium and water absorption, decrease in K+ and H+ secretin
• have hyperkalemia
• have low renin

Cause - primary functional adrenal tumour

• ACTH secreting tumour
• exogenous glucocoritcoid

Question 4

Partial loss of function in glucocorticoid receptor

Answer 4

• get a large increase of cortisol to try and get this to work
• however get the symptoms of increase in mineralocorticoid receptor activation (secondary mineralocorticoid effects)

Question 5

Loss of function of mineralcorticodi receptor

Answer 5

similar to aldosterone decrease

-lots of salt and water loss, high potassium, low sodium

Question 6

ACTH receptor loss of function mutation

Answer 6

low cortisol levels

• adrenal gland does not develop properly
• no cortisol and androgen formation
• same signs as glucocorticoid deficiencey

Question 7

Karyotype XX

• small penis, looks male
• no testis
• normal uterus

What could this be?

Answer 7

Defect in cortisol synthesis

-low cortisol levels lead to high acth levels, which stimulates the adrenal cortex excess production of adrenal precursor and adrenal hyperplasia

not able to convert cortisol so it forms different androgens and makes more testosteroen and causes the virilisation in tehse girls

Question 8

Young boy, normal sized testis but large penis, growing very fast , high BP, high sodium, and low K, very dark

Answer 8

Dark skin - primary problem with acth

• small testis - know that androgens did not come from testis
• sex steroids - either form gonads or adrenlas - must be adrenals
• congenital adrenal hyperpalsia or fucntional adrenal neoplasm
• • more likely to be block in an enzyme makign coritsol because is dark and making msh
• can make another androgen that cna bind to mineralcortiocid receptor
• so get low renin and aldoesterone
• lack of cortisol drives this to make increases levels of this hormone

management - supress acth - give glucocorticoids

• bone age - advanced - turn of the outside hormones, turn off your own puberty
• treat hypertension

Question 9

Infant with crushing sydnrome

Answer 9

• however exogenous androgen - from a steroid cream

- low cortisol levels in body because have exogenous high