Endocrinology: Adrenal Disease Flashcards
(41 cards)
State the effects of cortisol on glucose metabolism [3]
Increases glucose levels
Increased glucose through stimulation of hepatic and renal gluconeogenesis,
and glycogenolysis
Reduces sensitivity to insulin in peripheral tissues
Increased efficacy of glucagon / adrenaline
Which bone disease can Cushing’s syndrome / disease lead to? [1]
Osteoporosis (due to excess cortisol)
State the effect of cortisol on protein metabolism [2]
Protein breakdown and muscle wasting
Reduces bone formation leading to bone loss
Name 4 causes of hypoadrenalism [4]
- Addison’s–autoimmuneadrenalitis
- Infections: TB/fungal
- Waterhouse-Friedrichson syndrome –adrenal haemorrhage due to meningococcal infection
- Congenital adrenal hyperplasia
- Drugs: long term steroids suppressing adrenals. Ketoconazole
What are signs of Addison’s disease? [5]
- anorexia & weight loss
- fatigue, generalised weakness,
- increased pigmentation - particularly in mouth, scars and skin creases
- dizziness on standing
-
nausea & vomiting
(Remember Addison’s is due to decreased cortisol and aldosterone)
State 5 signs of Addison’s disease [5]
(Addison’s disease refers specifically to when the adrenal glands have been damaged, resulting in reduced cortisol and aldosterone secretion)
Postural hypotension (>10 mmHg)
Vitiligo (came up in CBL)
Depression & pyschosis
Abodominal pain (w/ n & v)
Flu like myalgias
Pigmentation – buccal, scars, skin crease
Addison’s should be considered in all patients who exhibit which symptom? [1]
Unexplained abdominal pain or vomiting
How may an Addisonian crisis present? [5]
Acute presentation of severe adrenal insufficiency, where the absence of steroid hormones (cortisol and aldosterone) leads to a life-threatening emergency. They may present with:
- Reduced consciousness
- Hypotension
- Abdominal pain
- Nausea and vomiting
- Hypoglycaemia
- Hyponatraemia and hyperkalaemia
- Pigmentation – buccal, scars, skin crease
What does this picture indicate? [1]
Pigmentation in the mouth - Addisons
Which skin pathology is a sign of Addisons? [1]
Vitilgo
When taking blood tests, what would hypoadrenalism have? [6]
- Na & K levels
- Urea levels
- Glucose levels
- Type of anaemia
- Ca levels
- Effect on leukocytes
Low Na; High K
High urea (increased salt and water loss / dehydration)
Low glucose
Normocytic anaemia
Eoisinophilia
Mild hypercalcemia
Aside from running blood tests, what would you test for with a patient you suspect of having hypoadrenalism? [4]
- Short synthetic ACTH [synacthen] test
- If synacthen test not available: Random cortisol and ACTH: 9am ATCH raised
- 21 hydroyxlase adrenal antibodies positive in 80% patients
- Abdomen x-ray (if TB has caused calcification of adrenal glands)
What is the diagnostic test of choice for hypoadrenalism? [1]
Short synthetic ACTH [synacthen] test
Describe the method of conducting a short synthetic ACTH [synacthen] test
- A dose of Synacthen, (synthetic ACTH).
- The blood cortisol is checked before and 30 and 60 minutes after the dose.
- The synthetic ACTH will stimulate healthy adrenal glands to produce cortisol.
- The cortisol level should at least double.
- A failure of cortisol to double indicates either:
- Primary adrenal insufficiency (Addison’s disease)
- Very significant adrenal atrophy after a prolonged absence of ACTH in secondary adrenal insufficiency
Autoantibodies directed at the adrenal cortex to the autoantigens [] and [] can be seen in 70% of patients with idiopathic or primary Addison’s disease
Autoantibodies directed at the adrenal cortex to the autoantigens 21-hydroxylase and 17 alpha hydroxylase can be seen in 70% of patients with idiopathic or primary Addison’s disease
Management of Addisonian crisis;
Acute treatment? [2]
Long term treatment? [2]
Acute treatment:
* 0.9% saline
* IV hydrocortisone 100mg bolus stat; then IM doses until can take tablets
Long term treatment:
* Oral hydrocortisone – usually 10mg/5mg/5m
* Oral fludrocortisone (mineralocorticoid)
Long term management of Addisonian crisis is:
Oral hydrocortisone
Oral fludrocortisone
What are the doses and dosing regimen like? [2]
Oral hydrocortisone – usually 10mg/5mg/5mg(reduce dose during the day so can sleep at night (cortisol is lowest at midnight))
Oral fludrocortisone - once daily; first thing at morning. Dose is titrated around BP; normally 100 - 200 mg dose
What blood results would you expect to see a ptx with Cushings syndrome? [3]
Hypokalaemia: due to excess cortisol having a mineralocorticoid effect (acts on aldostorone receptors)
Hyperglycaemia
High white blood cell count: Polycythaemia, Neutrophilia, Lymphopenia
What would you expect a midnight salivary or serum cortisol levels to be like in a Cushing’s syndrome patient? [1]
Elevated (normally these are lowest)
Name and explain the diagnostic test of choice for Cushing’s syndrome
Normal: dexamethasone suppresses cortisol release from adrenal glands
Cushings: cortisol levels are high despite dexamethasone suppressing cortisol release
State 4 reasons that can cause increase in cortisol, which would give false positive results in a dexamethasone suppression test [4]
depression
alcohol excess
obesity
acute illness
What would differing ACTH levels indicate about the whether Cushings is ACTH dependent or independent?
ACTH elevated: more likely to be pituitary ectopic disease causing an increase in ACTH and therefore more cortisol - ACTH dependent
ACTH suppressed: more likely to be adrenal disease causing more cortisol - ACTH independent
How would you differ imaging to determine whether Cushings was ACTH dependent or ACTH independent? [2]
If ACTH-dependent: Pituitary vs ectopic
- MRI image of the pituitary
If ACTH-independent:
- imaging of adrenals/chest
Ectopic ACTH dependent Cushings is often caused by which type of cancer? [1]
ectopic ACTH: small cell lung cancer
