Circadian Rhythms, adrenal insufficiency and management Flashcards
When you go to sleep, what happens to your cortisol levels?
They drop
Cortisol peaks at ___ times
meal
Light information goes to hypothalamus which regulates ___ secretion
CRH
What hormone increases at night?
Melatonin
What is Primary Adrenal insufficiency?
Addison’s Disease
Adrenal glands make too little cortisol
What causes secondary adrenal insufficiency?
Hypopituitarism
eg macroadenoma, radiotherapy, congenital
What can cause tertiary adrenal insufficiency?
Suppression of HPA
Steroids, oral, inhaler, creams
What are common symptoms of adrenal insufficiency?
Fatigue, weight loss, poor recovery from illness, adrenal crisis, headache
What are common past histories for adrenal insufficiency?
TB
Post partum bleed
Cancer
Family history of autoimmunity
Any steroids
What are signs of adrenal insufficiency?
Pigmentation (due to high ACTH release together with melanin eg in primary adrenal insufficiency) and pallor
Hypotension
Low sodium and high potassium (due to loss of aldosterone)
When are cortisol and ACTH tests taken?
8:30-9:00 am
In primary adrenal insufficiency, what will there be lower levels of?
Cortisol, aldosterone and sex androgens
In primary adrenal insufficiency, there will be increased levels of r___ due to low levels of aldosterone
renin
What is a Synacthen test?
Blood test
Inject ACTH
after 30 minutes, test for cortisol again.
If cortisol level more than 450 nmol/l then adrenal insufficiency is unlikely
What are the main investigations for adrenal insufficiency?
Cortisol and ACTH test at 9am
Synacthen Test (inject ACTH)
How to investigate Addison’s disease
Send adrenal antibodies. Negative antibodies leads to CT scan of adrenals.
Very long chain fatty acid test (test for rare disease, adrenal leukodystrophy)
17-OHP test (type of androgen, raised levels suggest adrenal hyperplasia)
Imaging
Genetic testing
Investigating Secondary adrenal insufficiency
Any steroids
Imaging
Genetic
IF a healthy individual becomes unwell then they will increase production of cortisol.
However, for adrenal insufficiency patients, they need to take medication to increase cortisol eg h____
hydrocortisone
For patients who get adrenal crisis, an i_____ of hydrocortisone is given so if at home, can take and call ambulance
injection
If in hospital have suspected adrenal crisis, try to take blood before immediately giving h______
hydrocortisone
Patients with adrenal insufficiency must carry what with them?
A steroid card and medic-alert (and 10 x 10mg hydrocortisone tablets)
How to treat adrenal insufficiency
Glucocorticoid replacement:
Usually hydrocortisone, 3 doses each day. Given by weight.
Mineralocorticoid treatment to replace aldosterone, aim for renin in upper half of normal range
Androgen replacement, DHEA replacement
What tablets can be given to children who require smaller doses of hydrocortisone?
Alkindi - have HC granules in capsules, can be sprinkled on food
Advantages of salivary cortisol testing
Non-invasive
Stress-free sampling
Can be performed at home
Relatively cheap
Easy
You can/cannot harm yourself in the short-term taking extra steroid?
Cannot
