Hyposecretion of Anterior Pituitary Hormones Flashcards

1
Q

What is the difference between primary, secondary and tertiary endocrine gland disease?

A

Primary: problem with the endocrine gland/hormone released
Secondary: problem with the pituitary gland/hormone released
Tertiary: problem with the hypothalamus

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

What is the term given to decreased production of all anterior pituitary hormones?

A

Panhypopituitarism

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

List 3 characteristics of congenital panhypopituitarism

A

Deficient in GH + at least 1 other anterior pituitary hormone
Short stature
Hypoplastic anterior pituitary on MRI

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

In what order does loss of secretion occur?

A
Usually develops in adults with progressive loss of pituitary secretion
Gonadotrophins  
GH
Thyrotrophin 
Adrenocorticotrophin 
Prolactin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are 3 main types of panhypopituitarism?

A

Simmond’s Disease
Sheehan’s Syndrome
Pituitary Apoplexy

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

Describe the symptoms experienced due to lack of FSH/LH, ACTH and TSH in Simmond’s disease

A

FSH/LH: Reduced libido, Secondary amenorrhoea, Erectile dysfunction
ACTH: Fatigue
TSH: Fatigue

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

State the cause of Sheehan’s syndrome and describe its onset.

A

Specific to postpartum women, secondary to hypotension caused by PPH.
Pituitary enlarges in pregnancy (lactotroph hyperplasia)
PPH reduces blood supply, causes pituitary infarction and thus hypopituitarism

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

What is pituitary apoplexy? Describe its onset.

A

Intra-pituitary haemorrhage or infarction.
Dramatic presentation, rapid onset
May be 1st presentation of pituitary adenoma
May be precipitated by anti-coagulants

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

Why is a single measurement of most hypothalamic hormones not useful?

A

Most hypothalamic hormones tend to be released in pulses

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

What do you do to test if someone is producing a hormone?

A

Stimulated Pituitary Function Test

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

What are the effects of a lack of somatotrophin in children and in adults?

A

Children: short stature (2 SDs < mean)
Adults: loss of GH effects are less clear

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

State 7 causes of short stature.

A
Genetic  
Emotional deprivation  
Endocrine disorders
Malnutrition 
Malabsorption
Skeletal dysplasias
Systemic disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe 3 causes of short stature, each with their error being in a different part of the growth axis

A

Hypothalamic dysfunction, lack of GHRH (PWS)
Lack of GH (Pituitary dwarfism)
GH receptor defect (Laron dwarfism)

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

What are most endocrine-related causes of short statue due to (with reference to the HP axis)?

A

Decreased production of GHRH

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

State which other hormones are produced in response to GH stimulation, where they are produced and their effects.

A

IGF I = insulin-like growth factor I + IGF II
Produced in LIVER
Mediate growth

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

State 3 characteristics of achondroplasia

A

Mutation in FGF receptor 3
Average size trunk
Short arms + legs

17
Q

Name 4 causes of acquired GH deficiency in adults

A

Trauma
Pituitary tumour
Pituitary surgery
Cranial radiotherapy

18
Q

What test is primarily used to diagnose GH deficiency?

A

Insulin-induced hypoglycaemia

Hypoglycaemia is a potent stimulus for GH release

19
Q

State 3 other triggers for an increase in GH release.

A

GHRH + Arginine (i.v.)
Glucagon (i.m.)
Exercise (in kids)

20
Q

Describe how the insulin-induced hypoglycaemia test is used to test GH secretion.

A

Normal: massive rise in GH secretion

GH Deficiency: GH response will be reduced

21
Q

For each of the following anterior pituitary hormone deficiencies, state the replacement used and the parameter that is monitored during treatment:

a. ACTH
b. TSH
c. Women - LH/FSH
d. Men - LH/FSH
e. GH

A
a. ACTH 
Give hydrocortisone 
Monitor serum cortisol 
b. TSH 
Give thyroxine 
Monitor serum fT4
c. Women – LH/FSH 
Give E2 + progestagen
Monitor symptom improvement + withdrawal bleeds
d. Men – LH/FSH 
Give testosterone
Monitor symptom improvement + serum testosterone
e. GH
Give GH  
Monitor IGF I or use growth chart (kids)
22
Q

How is the human recombinant GH administered, how frequently must it be given and what further action is taken?

A

Subcutaneous injection daily

Monitor clinical response + adjust dose based on IGF-1 levels

23
Q

State 4 signs and symptoms of GH deficiency in adults.

A

Reduced lean mass, Increased adiposity, Increased waist: hip ratio
Decrease plasma HDL + increased LDL
Reduced muscle strength + bulk
Impaired psychological wellbeing + quality of life

24
Q

Name 5 potential benefits of GH therapy in adults

A

Improved body composition
Improved muscle strength + exercise capacity
Normalisation of HDL-LDL
Increased bone mineral density
Improved psychological wellbeing + quality of life

25
Q

What are the potential risks of GH therapy in adults?

A

Increased susceptibility to cancer (but no evidence to support this)
Expensive

26
Q

List the anterior pituitary hormones

A
FSH + LH
Prolactin 
Growth Hormone
Thyroid Stimulating hormone
ACTH
27
Q

What are the general causes of hypopituitarism?

A

Congenital (rare)

Acquired

28
Q

List 8 causes of acquired panhypopituitarism

A
Tumour
Radiation
Infecion
Traumatic brain injury
Infiltrative disease
Inflammatory
Pituitary apoplexy
Peri-partum infection
29
Q

Describe presentation of Sheehan’s syndrome

A

Lethargy
Anorexia/ Weight loss
Failure of lactation
Failure to resume menses post-delivery

30
Q

Why may pituitary apoplexy/adenoma cause visual field defects and headaches?

A

Compresses optic chiasm
Causes bitemporal hemianopia (loss of outer fields)
If squashing CN 4 or 6 in cavernous sinus = Diplopia
If squashing CN 3 = Ptosis

31
Q

Describe a stimulated pituitary function test

A

Induce hypoglycaemia
Causes patient to produce GH + ACTH + hence cortisol (measured)
Give TRH to stimulate TSH (measure)
Give GnRH to stimulate FSH/ LH (measure)

32
Q

What form of radiological test may be used to diagnose hypopituitarism?

A

MRI

May reveal specific pituitary pathology e.g. haemorrhage, adenoma, empty sella

33
Q

What is used to predict adult height?

A

Mid parental height