Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

endo > Adrenals > Flashcards

Adrenals Flashcards

1
Q

What does the adrenal cortex do

A

Produced steroids -
Glucocorticoids e.g. cortisol, which affect carbohydrate, lipid, and protein metabolism
Mineralocorticoids - aldosterone, which control sodium and potassium balance
Androgens - sex hormones which have a weak effect until peripheral conversion to testosterone and dihydrotestosterone

Layers of the adrenal cortex
G - glomerulosa - mineralocorticoids
F - fasiculata - glucocorticoids
R - reticularis - androgens

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

How does the adrenal cortex become stimulated

A

Corticotropin releasing factor - from hypothalamus stimulates ACTH release from ant pit
That stimulates cortisol and androgen production

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

How is cortisol excreted

A

Urinary free cortisol various 17-oxogenic steroids

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

What is Cushing’s syndrome

A

Clinical state produced by chronic glucocorticoid excess and loss of normal feedback mechanisms of the HPA axis And loss of the circadian rhythm of cortisol release - inc release on waking

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

What are the main causes of Cushing’s syndrome

A

Exogenous steroids - iatrogenic and used by patient for other purposes
The other main type is ACTH producing pituitary adenoma -
Cushings disease
Rarer: adrenal adenoma, carcinoma producing cortisol
Cancers such as small cell lung ca and carcinoid tumours producing ACTH which acts on the adrenals inc cortisol

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

What are the symptoms of Cushing’s syndrome

A

Weight gain, mood change (depression, lethargy, irritability, psychosis), proximal weakness, gonadal dysfunction (irregular menses, hirsutism, erectile dysfunction), acne, recurrent Achilles’ tendon rupture, occasionally virilisation if female - become more masculine looking

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

Signs of cushings

A

Central obestity, plethoric, moon face, buffalo hump, supraclavicular fat distribution, skin and muscle atrophy, bruises, purple abdominal striae, osteoporosis, inc glucose, infection prone , poor healing,

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

Tests not done in cushings

A

Random cortisol as it affected by many things
Such as time of day, illness, stress
Also imaging cannot be relied upon and adrenal incidentalomas do not cause any problems in many but many have them and same with some pituitary adenomas and some ACTH producing micro adenomas are too small to be seen on scans

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

Tests done in investigating suspected Cushing’s syndrome

A

1) find a raised cortisol
Then you do tests that localise where the cortisol is coming from
1st line tests
-Overnight dexamethasone suppression test
1mg dexamethasone PO midnight do serum cortisol at 8 am
Normally cortisol would be suppressed below 50 but in Cushing’s syndrome it is not
- 24 hr urinary free cortisol alternative
2nd line tests
-48hr dexamethasone suppression test
Give measure cortisol at 0 and 48 hr- no suppression seen so still high
-48hr high dose dexamethasone suppression test
Pituitary (there would be suppression) from other ectopic (no suppression)
-midnight cortisol - blood or saliva at midnight cortisol should be lowest but in cushings the circadian rhythm is lost therefore may still be high
Localisation tests
If 1st and 2nd line +ve then do plasma ACTH- if undetectable = adrenal adenoma - CT/MRI adrenals
If ACTH detectable distinguish pituitary from ectopic - high dose suppression or CRH test - cortisol rises with pit disease not ectopic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What to do if cushings disease found as the pituitary is implicated

A

MRI/CT of the pituitary and consider bilateral inferior petrosal blood sampling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What to do if an ectopic cause is indicated as the reason for the Cushing’s syndrome

A

Hunt for the source
CT chest abdo pelvis
MRI neck thoracand abdo
Hunting small cell lung and small carcinoid tumours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is Addison’s disease

A

Primary adrenocortical insufficiency
Rare can be fatal
There is destruction of the adrenal cortex leading to glucocorticoid and mineralocorticoid deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Causes of Addison’s disease

A 
In the Uk autoimmune 
Other causes TB - commonest worldwide
Adrenal mets
Lymphoma
Opportunity infections in HIV
Adrenal haemorrhage 
Anti-phospholipid syndrome
Congenital - late onset CAH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the cause of secondary adrenal insufficiency

A

Commonest cause is iatrogenic due to long term steroid use
Which suppresses the HPA
Only becomes apparent on steroid withdrawal
Rare - HP disease leading to dec ACTH

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

Symptoms of Addisons disease

A 
Lean 
Tanned
Tired 
Tearful 
\+/-weakness, anorexia, dizzy, faint, flu-like, myalgia, arthralgia
Mood depressed
GI N/V abdo pain diarrhoea, constipation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Signs of Addison’s disease

A

Hyperpigmented palmar creases and bucks mucosa
Inc ACTH, cross reacts with melanin receptors postural hypotension
Vitilogo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Biochemistry of Addison’s disease

A 
Low Na+
High K+ - due to low mineralocorticoid - aldosterone 
Low glucose - due to cortisol
Uraemia
Inc Ca2+
Eosinophilia
Anaemia
18
Q

What test doe you do for Addison’s disease

A

Short synacthen test
Do plasma cortisol half hour before synacthen given if 30 min cortisol over 550 Addison’s can be excluded
9am ACTH inappropriately high >300

19
Q

How to assess mineralocorticoid status

A

Plasma renin and aldosterone

20
Q

Tx Addison’s

A

Replace the steroids
15-25mg daily
Fludrocortisone to correct the mineralocorticoid
Adjust on clinical grounds

21
Q

What should steroid users wear

A

Bracelet declaring steroids use

22
Q

Advice when sick in Addison’s disease

A

Double dose

23
Q

What is hyperaldosteronism

A

Excess production of aldosterone, independent of the renin-angiotensin system

24
Q

What does hyperaldosteronism cause

A

Inc sodium and water retention and dec renin release

25
Q

When to consider hyperaldosteronism

A

High BP, hypokalaemia, or alkalosis in someone who is not on diuretics

26
Q

Symptoms of hyperaldosteronism

A

Often asymptomatic o signs of hypokalaemia

Weaknesss cramps, parasthesia, polyuria, polydipsia, inc BP but not always

27
Q

Causes of hyperaldosteronism

A

Solitary aldosterone producing adenoma linked to mutations in K+ channels this is conns syndrome
Bilateral adrenocortical hyperplasia
Rare- carcinoma, GRA hereditary where aldosterone gene becomes under the control of ACTH

28
Q

Syndrome associated with hyperaldosteronism

A

Conns syndrome

29
Q

Tests in hyperaldosteronism

A 
U&E
Renin 
aldosterone 
Adrenal vein sampling 
Genetic - GRA
30
Q

Tx conn’s

A

Laparoscopic adrenalectomy

Spironolactone for 4 weeks pre-op controls BP and K+

31
Q

Tx of hyperplasia

A

Treated medically spironolactone or amiloride

32
Q

Tx of GRA

A

Dexamethasone normalises biochemistry but not alway BP if high use spironolactone as an alternative.

33
Q

Tx adrenal carcinoma

A

Surgery +/- post-op adrenolytic therapy with mitotane - prognosis is poor

34
Q

What is secondary hyperaldosteronism

A

Due to high renin from dec renal perfusion e.g. renal artery stenosis, accelerated hypertension, diuretics, CCF or hepatic renal failure

35
Q

What is Bartters syndrome

A

This is a major cause of congenital (autosomal recessive) salt wasting - via sodium and chloride leak into the loop of henle via mutations in channels and transporters.
Presents in childhood with failure to thrive, polyuria, polydipsia
Sodium loss leads to volume depletion, causing inc renin and inc aldosterone production. Leading to hypokalaemia, and metabolic acidosis
Tx - k+ replacement, NSAIDS (to inhibit prostaglandins) and ACEi

36
Q

What is a phaeochromocytoma

A

Rare catecholamine producing tumour
arise from sympathetic para ganglia cells
Which are collections of chromaffin cells
Usually found in the adrenal medulla

37
Q

Are phaeochromocytoma not found in the adrenals

A 
No 
Xtra adrenal 
They are rare 
Often found in the formation of the aorta the organs of zuckerkandl 
10% extra adrenal
38
Q

Can phaeochromocytoma metastasise

A

Yes 10% do

39
Q

Are phaeochromocytoma familial

A

10% are

FHx crucial can be offered genetic testing as some gene mutations have been shown to inc risk

40
Q

What is the classic triad iof phaeochromocytoma

A

Episodic headache, sweating,and tachycardia

+/- deranged up down or normal BP

41
Q

Tests for phaeochromocytoma

A

24hr urine metanephrines
Plasma metanephrines
Inc WCC
Imaging MRI/CT abdo pelvis

42
Q

Tx of phaeochromocytoma

A

Surgery
Remove
Need to prep with an alpha blockade and then beta blockade
This is to prevent crisis from unopposed alpha adrenergic stimulation

endo (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions