QuestionSBA
QuestionChoice
This is a test used in suspected Addison's disease. Patients presenting with Addison's disease usually appear tanned, lean, fatigued, and notice significant weight loss.
10005399
d
Short ACTH stimulation test
QuestionChoice
This is a test used in suspected acromegaly. The clinical presentation would be with increasing size of hands and feet, frontal bossing, headache, macroglossia, and proximal myopathy.
10005398
c
Oral glucose tolerance test
QuestionChoice
The most likely diagnosis in this case is Cushing's syndrome. The low-dose (overnight) dexamethasone suppression test is the most sensitive test to diagnose Cushing's syndrome and is now used first-line. In patients with Cushing's disease, there would be no change in cortisol levels. Patients without Cushing's disease will have reduced cortisol levels.
10005396
a
Low-dose (overnight) dexamethasone suppression test
QuestionChoice
The high-dose dexamethasone suppression test is a localisation test once Cushing's syndrome has been diagnosed. If cortisol and ACTH are both suppressed, this is indicative of Cushing's disease. If both are NOT suppressed this indicates an ectopic ACTH syndrome. Finally, if cortisol is not suppressed but ACTH is then this is Cushing's syndrome due to other causes- for example an adrenal adenoma.
10005400
e
High-dose dexamethasone suppression test
QuestionChoice
This is a localisation test. CRH (Corticotrophin Releasing hormone) is given to test the responsiveness of the pituitary in producing ACTH and then cortisol. If the syndrome is of a pituitary source, cortisol rises. If it is of ectopic/adrenal source, there is no change in cortisol.
10005397
b
CRH stimulation test
QuestionComment
Low dose is first line, but I thought you then performed high dose to confirm the diagnosis?
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Concept
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Cushing's syndrome
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Endocrine
13626
A 44-year-old woman is seen in the endocrinology clinic with a five-week history of fatigue and weight gain. She has a past medical history of reflux and she denies recent infectious symptoms. On examination, she has a heart rate of 95 bpm and blood pressure of 158/98mmHg. Her skin appears thinned and there are numerous prominent bruises across her upper arms.

Which of the following initial tests is most likely to make the diagnosis?
a