S10 Adrenal Disorders Flashcards
“The deeper you go, the sweeter it gets” so what is each level of the adrenal cortex related to?
Zona glomerulosa - mineralcorticoids - salt
Zona fasciculata - glucocorticoids - sugar
Zona reticularis - androgens - sex
What is the clinical presentation if a person has a cortisol deficiency?
- weakness
- tiredness
- weight loss
- hypoglycaemia
What is the clinical presentation if a person has a mineralocorticoid deficiency?
- dizziness, low Na+, high K+
What is the clinical presentation if a person has an androgen deficiency?
- low libido
* loss of body hair in women
What is the clinical presentation of a person with a cortisol excess?
- weight gain
* cushingoid features
What is the clinical presentation of a person with a mineralocorticoid excess?
- high BP
* low K+
What is the clinical presentation of a person with a androgen excess?
- increased male characteristics in women
What is the clinical presentation if there is excess ACTH released from the pituitary?
Skin pigmentation due to melanocytes stimulation - seen in Addison’s and ACTH-driven Cushing’s
What is the clinical presentation of someone with excessive catecholamine secretion?
Acute episodes of:
- sweating
- anxiety
- palpitations
- high/low BP
- collapse
What biochemical tests do you do if someone has a suspected adrenal hormone deficiency?
- electrolytes - low Na+, high K+ if aldosterone deficiency, if ACTH deficiency, only Na+ is low and K+ is normal
- 0900 basal cortisol - low (should be high in morning)
- stimulation test, inject with synthetic ACTH
What biochemical tests do you do if someone has a suspected adrenal hormone excess?
- electrolytes - low K+, high Na+
- midnight cortisol - high (should be low)
- 24hr urine cortisol - high
- suppression test - failure to suppress
- androgens and derivatives - high
What biochemical tests do you do to assess the adrenal medulla function?
- 24 hour urine catecholamines - adrenaline, NA, dopamine, 3-methoxy-tyramine
- 24 hour urine metanephrines (breakdown products of adrenaline and NA) - metadrenaline, normetadrenaline
- plasma metanephrines (more sensitive than 24hr urine)
Avoid coffee, coke, bananas, chocolate and vanilla before testing
What condition are high levels of catecholamines, in 24hr urine testing, suggestive of?
Phaeochromocytoma
What radiological imaging is used in adrenal disease?
- CT scan
- MRI scan
- functional imaging - MIBG scan (shows uptake of adrenaline/NA phaeochromocytoma) and PET scan
What are the signs and symptoms of Addison’s disease?
- fatigue and weakness
- anorexia and weight loss
- abdominal pain and nausea
- dizziness
- pigmentation
- underweight and signs of weight loss
- general malaise
- vitiligo and thyroid autoimmune diseases
- postural hypotension
- pigmentation
What can cause primary adrenal failure?
- autoimmune
- infection
- infiltration
- malignancy
- genetic
- vascular
- iatrogenic
What are the clinical features of adrenal crisis?
- collapse
- hypotension
- dehydration
- pigmentation
- coma
What are the blood test results of someone in adrenal crisis?
- low Na+
- high K+
- high urea
- high creatinine
How do you treat adrenal crisis?
- quick rehydration with fluids
- IV hydrocortisone
- correction of hypoglycaemia
- find out the precipitating cause