ChemPath: Adrenal Disease Flashcards

1
Q

What are the five layers of the adrenal gland?

A
  • Capsule
  • Glomerulosa
  • Fasciculata
  • Reticularis
  • Medulla
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What can cause adrenal glands to appear wasted?

A

Addison’s disease

Long-term steroid use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can cause adrenal glands to become hyperplastic?

A

Cushing’s disease

Ectopic ACTH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

By what factor is the output of cortisol from the adrenals greater than the output of aldosterone?

A

About 1000 (aldosterone is measured in picomoles, cortisol is measured in nanomoles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many arteries and veins do the adrenal glands have?

A

57 small arteries

1 vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is a blood sample to measure adrenal output taken?

A

A cannula is placed through the IVC into the adrenal vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is the venous drainage different for the left and right adrenal glands?

A

Left - drains into the left renal vein

Right - drains directly into the IVC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What condition includes both primary hypothyroidism and Addison’s disease?

A

Schmidt syndrome (though it is now called Polyglandular Autoimmune Syndrome Type 2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the short synacthen test.

A
  • Measure cortisol and ACTH at the start of the test
  • Administer 250µg synthetic ACTH by IM injection
  • Check cortisol at 30 and 60 mins
  • Healthy people should produce >550nM of cortisol within 30 mins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the differential diagnosis for hypertension with an adrenal mass?

A
  • Phaeochromocytoma
  • Conn’s syndrome
  • Cushing’s syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the disastrous consequences of phaeochromocytoma?

A
  • Severe hypertension
  • Arrhythmia
  • Death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Outline the treatment of phaeochromocytoma.

A
  • Urgent alpha blockade (with phenoxybenzamine or phentolamine or doxazocin)
  • Some fluids may be given after the alpha-blocker to prevent reflex tachcardia
  • A beta-blocker should be given after the alpha-blocker to prevent reflex tachycardia
  • Patients should receive high-dose alpha and beta-blockade before surgery as the action of surgery can cause the release of catecholamines from the adrenals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name three genetic syndromes associated with phaeochromocytomas.

A
  • MEN2
  • Von Hippel Lindau syndrome
  • Neurofibromatosis type 1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the levels of aldosterone and renin in Conn’s syndrome.

A

High aldosterone

Low renin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

List some tests used in Cushing’s syndrome.

A
  • 9am cortisol
  • Midnight cortisol
  • Low-dose dexamethasone suppression test
  • Inferior petrosal sinus sampling (determines whether high levels of ACTH are from pituitary or ectopic from somewhere else)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe how low-dose dexamethasone suppression test is performed.

A
  • The patient’s baseline ACTH and cortisol is measured at the start
  • Then they are given 0.5mg dexamethasone every 6 hours for 48 hours
  • This should suppress cortisol to <50nM
  • inferior petrosal sinus sampling with CRH stimulation
  • allows us to figure out if if cortisol production is exogenous or endogenous
17
Q

What can be done right after a low-dose dexamethasone suppression to specify what is causing the increase in endogenous cortisol?

A

Measure ACTH plasma levels
Low ACTH - Adrenal Adenomas or Adrenal Carcinomas
High ACTH - Cushing Disease (pituitary-dependent) or Ectopic ACTH [IPSS to confirm Ectopic ACTH specfically]

18
Q

What proportion of endogenous Cushing’s syndrome is caused by Cushing’s disease?

A

85%

19
Q

What is pseudo-Cushing’s syndrome?

A

Obesity can change your metabolism of cortisol to produce a clinical syndrome that looks like Cushing’s syndrome

20
Q

List three endogenous causes of Cushing’s syndrome.

A

Pituitary-dependent Cushing’s disease

Adrenal adenoma

Ectopic ACTH

21
Q

What is this?

A

Adrenal Glands