Antidiuretic Hormone Disorders & Corticosteroids Flashcards
(32 cards)
What is diabetes insipidus characterized by?
Excess dilute urine and extreme thirst
What are the two types of diabetes insipidus?
- Pituitary (cranial)
- Nephrogenic (partial)
What causes pituitary diabetes insipidus?
Lack of vasopressin (ADH) production
What is the common treatment for pituitary diabetes insipidus?
Vasopressin or desmopressin
How does nephrogenic diabetes insipidus differ from pituitary diabetes insipidus?
Kidneys do not respond to ADH
What is the treatment for nephrogenic diabetes insipidus?
Thiazide diuretic (paradoxical effect)
How is desmopressin different to vasopressin?
- More potent than vasopressin
- Longer duration of action
- No vasoconstrictor effect
What are some side effects of desmopressin?
- Hyponatraemia
- Nausea
how does increased ADH lead to hyponatraemia?
Increased ADH = body stores too much water = dilutes salt concentration in blood = hyponatraemia
What is the treatment for inappropriate ADH secretion?
- Fluid restriction
- Demeclocycline
- Tolvaptan
What serious condition can occur with rapid correction of hyponatraemia using tolvaptan?
Osmotic demyelination = serious neurological events
What is the main MOA of mineralocorticoid steroids?
High fluid retention and low anti-inflammatory effect
Which mineralocorticoid steroid has the highest activity?
Fludrocortisone
what is fludrocortisone used to treat?
postural hypotension
What are some side effects of mineralocorticoid steroids?
- Sodium and water retention (hypertension)
- Potassium loss (hypokalaemia)
- Calcium loss (hypocalcaemia)
What is the main MOA of glucocorticoid steroids?
High anti-inflammatory effect and low fluid retention
Which glucocorticoid steroid has the highest activity?
Dexamethasone/betamethasone
What are common side effects of glucocorticoid steroids?
- Diabetes
- Osteoporosis
- Avascular necrosis
- Gastric ulceration
What are the side effects associated with all corticosteroids?
- Central serious chorioretinopathy
- Psychiatric reactions
What is the MHRA advice regarding use of corticosteroids?
report blurred vision or other visual disturbances - central serious chorioretinopathy
if a patient on corticosteroids begins to experience any of the following symptoms what should they do?
insomnia, irritability, mood change, suicidal ideation, behavioural disturbances
seek medical advice and withdraw treatment
What can prolonged use of corticosteroids lead to?
Adrenal atrophy which can last years after treatment ends
What is a potential consequence of abrupt withdrawal from corticosteroids?
Acute adrenal insufficiency, hypotension or death
What should be done to the dose of corticosteroids if a patient with adrenal insufficiency undergoes significant illness or surgery?
Temporarily increase corticosteroid dose or reintroduce if already stopped
