Adrenal insufficiency Flashcards
What is adrenal insufficiency?
When the adrenal glands do not produce enough steroid hormones, particularly cortisol and aldosterone
What causes primary adrenal insufficiency?
Damage to the adrenal glands
Addison’s disease
What is the most common cause of primary adrenal insifficiency?
Autoimmune causes
What is secondary adrenal insufficiency?
Inadequate adrenocorticotropic hormone (ACTH) and a lack of stimulation of the adrenal gland
What causes secondary adrenal insufficiency?
Loss of / damage to the pituitary
Give examples of some causes for secondary adrenal insufficiency?
Pituitary tumour
Surgery to the pituitary
Radiotherapy Sheehan’s syndrome
Trauma
What is tertiary adrenal insufficiency?
Inadequate corticotropic-releasing hormone (CRH) being released by the hypothalamus
What is a common cause of tertiary adrenal insufficiency?
Long-term oral steroid use
Hence the weaning of steroid courses
What are the clinical symptoms of adrenal insufficiency?
Fatigue, muscle weakness
Dizziness and fainting
Thirst and craving salt
Weight loss
Abdominal pain
Depression, reduced libido
What are two classic signs of adrenal insufficiency?
Bronze hyperpigmentation, particularly in creases
Hypotension, particularly postural hypotension
What causes bronze hyperpigmentation of the skin in adrenal insufficiency?
Excessive ACTH stimulating melanocytes to produce melanin
What is a key finding in adrenal insufficiency?
Hyponatraemia - low sodium
What test is diagnostic of adrenal insufficiency?
Short synacthen test
What is the ACTH level in primary adrenal insufficiency?
High
What is the ACTH levels in secondary adrenal failure?
Low
Which antibodies may be present in autoimmune adrenal insufficiency?
Adrenal cortex antibodies
21-hydroxylase antibodies
Which tests may be helpful in identifying a suspected structural pathology in adrenal insufficiency?
Adrenal gland CT
Adrenal gland MRI
When is the short synacthen test carried out?
In the morning
What is synacthen?
Synthetic ACTH
What two things can a failure of cortisol to double in the short synacthen test indicate?
Addison’s disease
Severe adrenal atrophy in secondary adrenal insufficiency
What medication is used to replace cortisol?
Hydrocortisone
What medication is given to replace aldosterone?
Fludrocortisone
What is the general management of adrenal insufficiency?
What are the two commonly used drugs?
Replacement steroids
Hydrocortisone + fludrocortisone
Why would a steroid dose be doubled in a patient with adrenal insufficiency?
During acute illness to match a normal steroid response
What is an adrenal crisis?
An acute presentation of severe adrenal insufficiency due to an absence of steroid hormones
What are the symptoms of an adrenal crisis?
Reduced consciousness
Hypotension
Hypoglycaemia
Hyponatraemia + hyperkalaemia
What is the management of an adrenal crisis?
ABCDE approach
IM or IV hydrocortisone
IV fluids
Careful monitoring of electrolytes
