Brainscape's Knowledge GenomeTM

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


See full index

Aneesha Flashcards BRS 2 > Hypopituitarism & Anterior Pituitary dysfunction > Flashcards

Hypopituitarism & Anterior Pituitary dysfunction Flashcards

1
Q

what are the anterior pituitary hormones

A

Growth Hormone
Prolactin
Thyroid stimulating hormone
Lutenising hormone/Follicle stimulating hormone
Adrenocorticotrophic hormone

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

where does the pituitary sit

A

Sella turcica of sphenoid bone

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

what does the anterior pituitary rely on?

A

the hypothalamus (to regulate function by releasing or inhibiting factors which travel via portal circulation)

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

what factors are released by the hypothalamus for the AP

A

growth hormone releasing hormone
somatostatin
thyrotrophin releasing hormone
dopamine
gonadotrophin releasing hormone
corticotrophin releasing hormone

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

what is a primary endocrine disease

A

disease where the pathology originates in the gland itself e.g thyroid, adrenal cortex (cortisol), gonads

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

what is a secondary endocrine disease

A

disease where the pathology originates in the signals from the hypothalamus/anterior pituitary

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

what is primary hypothyroidism

A

thyroid doesn’t produce thyroxine e.g. due to autoimmune destruction of thyroid gland
Hashimotos
T3&4 fall TSH high (we don’t measure TRH but that would also be high)

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

what is secondary hypothyroidism

A

eg pituitary tumour damaging thyrotrophs
Can’t make TSH
TSH falls
T3 & T4 fall (as no TSH)

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

what is primary hypoadrenalism

A

Addisons disease
adrenal cortex damaged/destroyed by autoimmune
ACTH high, cortisol low (we don’t measure CRH but that would also be high)

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

what is secondary hypoadrenalism

A

E.g. pituitary tumour damaging corticotrophs
adrenal cortex functioning,
but can’t make ACTH
ACTH falls, cortisol low

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

what is primary hypogonadism

A

eg destruction of testes (eg mumps) or ovaries (eg chemotherapy)
Testosterone (men) or oestrogen (women) fall, LH & FSH increase (we don’t measure GnRH but that would also be high)

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

what is secondary hypogonadism

A

eg pituitary tumour damaging gonadotrophs
Can’t make LH/FSH
LH/FSH fall, Testosterone/oestrogen fall

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

congenital causes of hypopituitarism

A

Rare. Usually due to mutations in transcription factor genes needed for normal anterior pituitary development e.g PROP1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the signs of congenital hypopituitarism

A

deficient in GH & at least one more hormone since birth
Short stature
Hypoplastic (underdeveloped) anterior pituitary on MRI

hypoplastic (underdeveloped) anterior pituitary

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

acquired causes of hypopituitarism

A

Tumours (adenoma, metastases, cysts)
radiation
infection (meningitis)
traumatic brain injury
pituitary surgery
inflammation (hypophysitis)/autoimmunity
pituitary apoplexy (haemorrhage, or less commonly infarction)
Peri-parturm infarction (Sheehan’s syndrome)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is hypophysitis

A

inflammation of the pituitary or infundibulum

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

what is pituitary apoplexy

A

Bleeding (haemorrhage) into pituitary or loss of blood flow (infarction) to the pituitary- more commonly bleed
Often sudden dramatic presentation in patients with pre-existing pituitary adenoma
May be first presentation of a pituitary adenoma
Can be precipitated by anti-coagulants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the name for complete loss of pituitary function (post. and ant.)

A

panhypopituitarism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the causes of pituitary apoplexy

A

haemorrhage

less commonly infarction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what procedures may cause radiotherapy-induced hypopituitarism
What factor is risk of HPA damage proportional to

A

Radiotherapy directly to pituitary (e.g. hormone producing pituitary tumor) or indirect (e.g. CNS tumor nearby)
Higher total radiotherapy dose (Gy)= higher risk of HPA axis damage

21
Q

what hormones are most sensitive to radioactivity

A

Growth hormone and gonadotrophins

22
Q

how long does the risk of radiotherapy persist for?

A

up to 10yrs, so annual assessment

23
Q

how does hypopituitarism affecting LH/FSH present?

A

reduced libido
secondary amenorrhoea
erectile dysfunction
reduced pubic hair

24
Q

how does hypopituitarism affecting ACTH present?

A

fatigue
Not a salt losing crisis (that’s RAAS)

25
Q

how does hypopituitarism affecting TSH present?

A

fatigue, weight gain

26
Q

how does hypopituitarism affecting GH present?

A

reduced quality of life, short stature in children

27
Q

how does hypopituitarism affecting Prolactin present?

A

inability to breastfeed

28
Q

what is sheehan’s syndrome?
In what regions of the world is it most common?

A

post-partum haemorrhage—> postpartum hypotension—>pituitary infarction—> postpartum hypopituitarism
Most common in developing countries

29
Q

what are the signs/ effects of sheehans syndrome

A

lethargy, anorexia, weight loss ((bc loss of GH, ACTH, TSH)), failure of lactation, failure to resume menses
Posterior pituitary not usually affected

30
Q

what happens to the pituitary during pregnancy

A

enlargement (lactotroph hyperplasia)

31
Q

what is the onset of pituitary apoplexy? What is it often precipitated by

A

dramatic and sudden
often precipitated by anti-coagulants

32
Q

what are the signs of pituitary apoplexy

A

severe sudden onset headache
visual field defect - bitemporal hemianopia (optic chiasm compression)
Cavernous sinus involvement leads to possible diplopia (IV, VI) and ptosis (III)

33
Q

what methods can be used to diagnose hypopituitarism

A

blood tests (biochemical diagnosis), dynamic pituitary function tests (stress test), pituitary MRI (radiology)

34
Q

what hormone dysfunction cannot be treated

A

prolactin

35
Q

what is the NICE guidance for treating hypopituitarism affecting GH?

A

Confirm GH deficiency on dynamic pituitary function test
Assess Quality of Life using specific questionnaire
daily injection of GHmeasure response by improvement in quality of life and plasma IGF-1

36
Q

how to confirm GH treatment is working

A

assess quality of life and measure response/improvement to this
Measure serum IGF-1

37
Q

what is the guidance for treating hypopituitarism affecting TSH

A

once daily levothyroxine
TSH will be low so you can’t use this to adjust dose as you would with primary hypothyroidism
Aim for fT4 above the middle of the reference range

38
Q

what is the guidance for treating hypopituitarism affecting ACTH?
What is the difficulty in this?

A

Replace cortisol rather than ACTH:
prednisolone once daily AM (e.g. 3mg)
or
hydrocortisone 3x daily (10mg/5mg/5mg)

Difficult to mimic diurnal variation of cortisol

39
Q

what is an adrenal crisis

A

Patients with primary adrenal failure (Addison’s) or secondary adrenal disease (ACTH deficiency) are at risk of dizziness, hypotension, vomiting, weakness triggered by intercurrent illness
can collapse and die

40
Q

what should patients taking replacement steroids be advised to do?

A

“Sick day rules”
keep steroid alert pendant/ bracelet
double steroid dose if fever/intercurrent illness
if unable to take tablets (e.g. vomiting), inject IM or come to A&E

41
Q

what are the guidelines for hypopituitarism affecting LH/FSH in men?

A

If no fertility is required- replace testosterone topically or IM, measure plasma testosterone. This doesn’t restore sperm production (dependent on FSH)
If fertility is required- induce spermatogenesis by gonadotropin injections
Measure testosterone and semen analysis
Sperm production may take 6-12 months

42
Q

when is fertility in men best conserved?

A

if secondary hypogonadism developed after puberty (gonads are right size/development)

43
Q

what are the guidelines for hypopituitarism affecting LH/FSH in women?

A

oral or topical oestrogen
addition of progesterone if uterus is intact to prevent endometrial hyperplasia- could increase risk of endometrial cancer
if fertility is required, carefully timed and gonadotrophin injections can induce ovulation (IVF)

44
Q

Does the term hypopituitarism refer to anterior or posterior pituitary dysfunction
Give examples of processes that can cause both anterior and posterior pituitary dysfunction

A

Generally refers to anterior pituitary dysfunction
Inflammation (hypophysitis) or surgery may cause posterior pituitary dysfunction too

45
Q

Why should you be cautious when interpreting basal plasma hormone concentrations?

A

Cortisol – what time of day?
T4 – circulating t1/2 6 days (so might take several days to have low T4 on test)
FSH/LH – cyclical in women
GH/ACTH - pulsatile

46
Q

What dynamic pituitary function tests are used in the diagnosis of hypopituitarism

A

ACTH/GH = ‘stress’ hormones
Hypoglycaemia (<2.2mM) = ‘stress’
Insulin-induced hypoglycaemia stimulates
GH release
ACTH release (cortisol measured)

TRH stimulates TSH release

GnRH stimulates FSH & LH release

47
Q

Radiological diagnosis of hypopituitarism

A

Pituitary MRI (CT not so good at delineating pituitary gland)

Posterior bright spot- posterior pituitary

May reveal specific pituitary pathology
eg haemorrhage (apoplexy), adenoma

Empty sella – thin rim of pituitary tissue

47
Q

Radiological diagnosis of hypopituitarism

A

Pituitary MRI (CT not so good at delineating pituitary gland)

Posterior bright spot- posterior pituitary

May reveal specific pituitary pathology
eg haemorrhage (apoplexy), adenoma

Empty sella – thin rim of pituitary tissue

Aneesha Flashcards BRS 2 (47 decks)

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