Steroid Abnormalities Flashcards
(22 cards)
What is the pathophysiology behind vitiligo?
Autoimmune disease that attacks melanocytes causing areas of depigmentation
- Hyponatremia
- Hypoglycaemia
- Hypotension
Are characteristic of which deficiency?
Glucocorticoid (cortisol)
- Hyponatremia
- Hyperkalemia
- Hypotension
- Metabolic acidosis
Are characteristic of which deficiency?
Mineralocorticoid deficiency (aldosterone)
The hyponatremic effects in cortisol deficiency are due to water retention/salt loss
Water retention
The hyponatremic effects in aldosterone deficiency are due to water retention/salt loss
Salt loss
Why does adrenal gland dysfunction cause skin pigmentation?
- Cortisol deficiency causes inc. ACTH
- ACTH contains aMSH (melanocyte stimulating hormone)
- Inc. POMC and inc. ACTH produces inc. MSH
What are some factors that distinguish simple obesity v excess glucocorticoids?
- Simple is progressive
- Simple is generalised
- Simple drives growth (height similar to parents)
Excess glucocorticoids:
- Adults have ___ obesity
- Children have ___ obesity
Truncal
Generalised
Glucocorticoid excess causes profound growth failure/stimulation and a crossing of percentiles downwards/upwards
Growth failure
Crossing of percentiles downwards
What are three signs of thinning skin (due to glucocorticoid excess)?
- Volacious striae
- Facial plethora
- Bruising
Why can cortisol have mineralocorticoid effects?
- Binds to mineralocorticoid and glucocorticoid receptor with equal affinity
- Usually has no MC effect bc metabolised rapidly
- Excess cortisol overrides kidney’s ability to break down cortisol
What are the DDx for Cushngs syndrome?
- Primary functional adrenal tumour
- ACTH secreting tumour (pituitary/ectopic)
- Exogenous glucocorticoid
Glucocorticoid resistance is associated with:
Inc/Dec. cortisol
Secondary ___ effects
Hyper/hypo androgenism
Fatigue/tiredness
Increased cortisol
Secondary mineralocorticoid effects
Hyperandorgenism
Pseudohypoaldosteronism is associated with:
Inc/Dec. aldosterone + renin
Inc/dec. ECF space
Inc/dec. serum K+ conc
Inc/dec. serum Na+ conc
Inc aldosterone + renin
Dec. ECF space
Inc. serum K+ conc
dec. serum Na+ conc
What are the findings in a patient with ACTH receptor loss of function mutation?
- Small non-functioning zona reticularis and fasiculata
- Severe cortisol deficiency from birth
17 OH progesterone elevation suggests a defect in the _____
Adrenal gland
17 OH progesterone elevation suggests a deficiency in which enzyme?
21 hydroxylase
A prepubertal testis is
4
What is congenital adrenal hyperplasia?
A group of autosomal recessive disorders, each of which involves a deficiency of an enzyme involved in the synthesis of cortisol, aldosterone, or both.
All steroid creams are absorbed ____
Systemically
What is the commonest cause of Cushings syndrome?
Exogenous steroid exposure
What are two key features of Addisonian Crisis?
Cardiovascular collapse and hypoglycaemia
