Endo: Adrenal Dysfunction Flashcards
2 main divisions of the adrenal gland
- cortex
- medulla
3 functional zones of the adrenal cortex
- zona glomerulosa (mineralocorticoids)
- zona fasiculata (glucocorticoids)
- zona reticularis (androgens)
what does the adrenal medulla produced?
catecholamines like Adr and NA
what’s the function of corticosteroids
- increase glycogenolysis
- increase gluconeogenesis
- increases lipolysis
- increases protein metabolism
- modulate the inflammatory response
what do the catecholamines do?
- increase heart rate and BP
- increase blood glucose
- preferential vasoconstriction
what is Cushing’s syndrome
adrenal problem which causes an excess in cortisol
what is Cushing’s disease
a Pituitary problem which causes an excess of cortisol due to ACTH hypersecretion
what can cause an excess of cortisol?
- adrenal problem
- pituitary problem
- ectopic tissue
- drug-induced
signs and symptoms of Cushing’s syndrome
- moon face
- plethoric face
- buffalo hump
- abdominal obesity
- purple striae
- hirsutism
- easy bruising
- hypertension
- osteopenia
- DM
- osteopenia
- impaired immune function
different diagnosis for Cushing’s syndrome
- severe obesity
- alcoholism
- bullaemia
- depression
what to look out for a history for Cushing’s syndrome
- weight gain
- hypertension
- difficulty in climbing stairs
- menstrual irregularities
- amenorrhea
- infertility
- impotence
- depression
- mood changes
- polyuria
- polydipsia
- uncontrolled glucose
- decrease BMD
- headaches
- darkening skin
when should you investigate?
- hypokalaemic metabolic acidosis
- unexplained obesity
- young people with difficult to contol HTN
- uncontrolled DM
- increasing body hair
- virilisation
- unexplained easy bruising
investigations for Cushing’s
- urinary free cortisol
- dexamethasone suppression test
- late night serum cortisol
- salivary cortisol level
what result is diagnostic for Cushing’s in urinary free cortisol
cortisol values 3-4x higher than the upper limit of normal cortisol (3 consecutive negative test would rule out Cushing’s syndrome)
how does the dexamethasone suppression test work?
glucocorticoids inhibit secretion of hypothalamic CRH and pituitary ACTH but do not directly affect adrenal cortisol production
which investigations allows the patient to take their own samples at home?
salivary cortisol level
radiological investigations for Cushing’s
- MRI/CT adrenal
- chol scan
which medication can you use to treat Cushing’s syndrome
ketoconazole, mitotane, metyrapone, aminoglutethimide (these interfere with the conversion of precursors to prevent the formation of cortisol)
which medications can you use to treat Cushing’s disease?
bromocriptine
what is Nelson syndrome
spectrum of symptoms and signs arising from an ACTH–secreting pituitary macroadenoma after a therapeutic bilateral adrenalectomy
what is Addison’s disease
when the adrenal glands do not produce enough steroid hormones
types of Addison’s disease
- primary (adrenal)
- secondary (pituitary)
how would you treat Addison’s disease?
- oral hydrocortisone
- oral fludrocortisone
what can be things that Addison’s patients present with?
- weakness
- pigmentation of skin
- weight loss
- abdominal pain
- hypoglycaemia
- salt craving
- diarrhoea
- constipation
- syncope/seizures
- vitilgo
- fever
what can cause Addison’s disease
- surgery
- anaesthesia
- volume loss
- trauma
- asthma
- hypothermia
- alcohol
- myocardial infarction
- fever
- hypoglycaemia
- pain
- psychosis or depression
- exogenous steroid withdrawal
presentation of an adrenal crisis
- severe hypotension
- hypoglycaemia
- hyponatremia
- hyperkalaemia
treatment of an adrenal crisis
- ABC
- fluid
- hydrocortisone IV
- fludrocortisone
- look for an underlying cause
what is Conn’s syndrome
when there is an aldosterone producing adenoma
what is GRH?
glucocorticoid remediable hypertension
what happens in Conn’s syndrome
- Na retention
- K loss
treatment of Conn’s syndrome
- high doses of spironolactone
- if you cannot control, surgery
what is late onset congenital hyperplasia?
deficiency of an enzyme in the cholesterol-aldosterone pathway and androgenic synthesis
types of LOCH
- 21-hydroxylase deficiency
- hirsutism
- virilisation
- precocious puberty
- infertility
- 11-betahydroxylase deficiency
- 17-alphahydroxylase deficiency
- 3-betahydroxysteroid deficiency
treatment for these enzyme deficiencies
- steroid replacement
- adrenalectomy (occasionally)
what is a phaeochromocytoma
catecholamine-secreting tumour derived from chromaffin cells
clinical manifestations of phaeochromocytoma
- elevated blood pressure
- increased cardiac contractility
- glycogenolysis
- gluconeogenesis
- intestinal relaxation
- arrhythmias
- myocarditis
- MI
- dilated cardiomyopathy
- LVF
- encephalopathy, seizures
- CVA
- headaches, palpitations, sweating, severe HTN
clinical signs of phaeo
- hypertension
- postural hypotension
- hypertensive retinopathy
- weight loss
- pallor
- fever
- tremor
- neurofibromas
- cafe au lair spots
- tachyarrhythmias
- pulmonary oedema
- cardiomyopathy
- ileus
what are MEN?
multiple endocrine neoplasia
what are the syndromes that fall under MEN2A?
- medullary Ca thyroid
- hyperparathyroidism
- phaeochromocytoma
- Hirschprung disease
what are the syndromes that fall under MEN2B?
- phaeochromocytoma
- medullary Ca thyroid
- mucosal neurofibromatosis
- marfanoid features
treatment for MEN syndromes
- surgery
- cover with alpha blocker
- isotonic saline
- beta blockers after alpha blockers
- phentolamine IV during surgery
