Endocrine Investigations Flashcards
First line investigation for thyroid cancer
And other investigations
1st) Ultra sound
Thyroid function
TSH receptor antibodies (TRAP)
No role for isotope scan/CT/MRI
screening test for excess cortisol (cushings)
best:
-overnight dexamtheasone suppression test
- 24 hr urinary free cortisol
Other:
-late night salivary cortisol
diagnostic test for cushings
low dexamethasone suppression test
(measure cortisol and aCTH at baseline and 48 hrs, normal response to supress. failure to supress diagnosis cushings syndrome. diagnoses cushings but not the cause)
diagnosis of primary aldosteronism
-confirm aldosterone excess
check aldosterone: renin ratio via saline supression test
- confirm subtype by doing abdo CT and AVS (adrenal venous sampling) to find out if its unilateral or bilateral
diagnostic test for Addisons
short synACTHen test
inject ACTH, in Addisons cortisol won’t increase as adrenal glands don’t work
conns syndrome Ix
blood biochem, urinary potassium loss >30mmol/day, adrenal CT scan (for adenoma)
diagnostic criteria for diabetes
fasting>7.0, random >11.1- if asymptomatic need 2 readings
hba1c> 48mmol diagnostic in symptomatic patient
test for acromegaly
1st line: Serum IGF-1 levels
confirm diagnosis: oral glucose tolerance test (OGTT) with serial GH measurement
phaecromocytoma IXs
do 24 hr urinary metanephrines, not catecholamines
What does simmonds test, test
Achilles tendon rupture
How to work out hyperosomlality
(2xNa) + glucose + urea
What is classed as hyperosomolality and what is hyperosmolality seen in
> 320mmol/L
Seen in HHS
initial investigation for someone with a fever who is taking carbimazole
blood test
this is to check for neutropenia (low platelets) which can be caused by carbimazole
high dose dexamethasone results for
pituitary adenoma
adrenal adenoma
ecoptic ACTH eg small cell lung cancer
PA: low acth, low cortisol (as acth dependant)
adrenal adenoma: low ACT, high cortisol (as ACTH independant)
ectopic ACTH: high ACTH, high cortisol (as ACTH isnt being produced from pituitary so does not respond to test)
clinical examinations for hypoparathyroidism
chvosteks sign: tapping parotid= facial twitching
trousseaus sign: carpal spasm (fingers adduct, wrist flexes) when bp cuff on