Endocrine Flashcards
How long is the treatment regime for Grave’s disease?
12-18 months
what electrolyte abnormality is seen in Cushing’s?
hypokalaemic metabolic alkalosis
what two tests are commonly used to confirm Cushing’s syndrome?
overnight dexamethasone suppression test
24hr urinary free cortisol
what is the most common cause for childhood hypothyroidism?
autoimmune thyroiditis
what is sick euthyroid syndrome?
changes in thyroid function tests when a patient is in hospital
often everything is low
In the majority of cases however the TSH level is within the normal range
Changes are reversible upon recovery from the systemic illness hence no treatment is usually needed
what is subacute thyroiditis?
occurs following viral infection and typically presents with hyperthyroidism
usually self-limiting
What diabetic medications cause weight loss?
canagliflozin - sglt2 inhibitor
exenatide - glp1 mimetic
How is HHS diagnosed?
- hypovolaemia
- marker hyperglycaemia»_space; 30mmol/l without significant ketonaemia or acidosis
- significantly raised serum osmolality (>320 mosmol/kg)
what is the main cause of primary hyperaldosteronism?
bilateral idiopathic adrenal hyperplasia
what are the features of primary hyperaldosteronism?
hypertension
hypokalaemia e.g. muscle weakness
alkalosis
What is carcinoid syndrome?
Group of symptoms that occur due to release of hormones by neuroendocrine tumours
Occurs when metastases are present in the liver and release serotonin into the systemic circulation
May also occur with lung carcinoid as mediators are not ‘cleared’ by the liver
What are the features of carcinoid syndrome?
flushing - often the earliest symptom
diarrhoea
bronchospasm
hypotension
right heart valvular stenosis
What is the treatment of Graves’ disease?
Carbimazole
what is the most common pituitary tumour?
pituitary adenoma - benign, non-secreting tumoue
which are the symptoms of a pituitary tumour?
headache
visual field defects
how is a pituitary tumour diagnosed?
MRI brain
screening tests for visual field defects
hormone tests as appropriate
what is the most common pituitary secreting tumour?
prolactin
what is the clinical presentation of prolactinoma?
women: oligomenorrhoea/amenorrhoea, galactorrhoea, infertility, vaginal dryness
men: reduced facial hair, erectile dysfunction
in both sexes: mass effects from tumour - headache, visual field defects
what are investigations for prolactinoma?
MRI brain: microadenoma appears as lesions in the pituitary, macroadenoma appears as space-occupying tumour
serum prolactin
how are prolactinomas managed?
pharmacological:
- dopamine agonist e.g. cabergoline - decrease in serum prolactin
- hormone replacement therapy
surgery:
- trans-sphenoidal resection indicated if failure of medical treatment
- radiotherapy
what are the causes of low magnesiumm?
drugs: diuretics, PPIs
total parenteral nutrition
diarrhoea: may occur with acute or chronic diarrhoea
alcohol
hypokalaemia
hypercalcaemia e.g. 2ndary to hyperparathyroidism
metabolic disorders
what are the features of low magnesium?
similar to hypocalcaemia:
- paraesthesia
- tetany
- seizures
- arrhythmias
- decreased PTH secretion
- ECG features similar to those of hypokalaemia
- exacerbates digoxin toxicity
What is the mechanism of action of ADH?
ADH stimulates synthesis of aquaporin-2 in the apical membrane of the collecting duct which promotes water reabsorption
What is the mechanism of action of ADH?
ADH stimulates synthesis of aquaporin-2 in the apical membrane of the collecting duct which promotes water reabsorption
how is primary hyperaldosteronism diagnosed?
plasma aldosterone/renin ratio is the first-line investigation
it should show high aldosterone levels alongside low renin levels
following this a high-res CT abdomen and adrenal vein sampling is used to differentiate between unilateral adenoma and bilateral sources of aldosterone excess
what is the management of primary hyperaldosternism?
adrenal adenoma: surgery
bilateral adrenocortical hyperplasia: aldosterone antagonist e.g. spironolactone