Hypo secretion of Anterior Pituitary Hormones

Question 1

Primary, secondary and tertiary endocrine gland diseases

Answer 1

Primary - Disorder at the endocrine gland
Secondary -disorder at the pituitary gland
Tertiary - disorder at the hypothalamus

Question 2

Panhypopituitarism

Answer 2

Decreased production of all anterior pituitary hormones

Question 3

Panhypopituitarism is caused by

Answer 3

Congenital –> rare defects or gene mutations in the genes involved in the development of the gland (e.g. PROP1). Hypo plastic pituitary gland

Acquired --> radiotherapy
tumours
infection
trauma
infiltrative disease
inflammatory
pituitary apoplexy
post partum infarction

Question 4

Panhypopituitarism causes progressive loss of the hormones in this order:

Answer 4

Gonadotrophin’s (LH and FSH)
GH
Thyrotrophin
Corticotrophin (ACTH)

Prolactin deficiency is uncommon

Question 5

Simmon’s disease is

Caused by…

Answer 5

Slow and insidious in onset. Panhypopituitarism

Various: infiltrative processes e.g. lymphocytic
Pituitary adenomas
Craniopharyngiomas
Cranial injury
Following surgery

Question 6

Simmond’s disease symptoms due to….. and include results in/symptoms:

Answer 6

decreased function of the thyroid, adrenals, and gonads

Result: Oligomenorrhoea/ secondary amenorrhoea in women
Impotence in men
Decreased libido
Tiredness
Waxy skin
Loss of body hair 
Hypotension

Question 7

Diagnosis of hypopituitarism can be made by

Answer 7

Biochemical diagnosis - using basal plasma levels of pituitary or target endocrine hormones. (hypothalamus pulsatile so one measurement shows nothing)

Provocation/stimulation test.
For ACTH and GH - induce stress, inject insulin to induce hypoglycaemia
For TSH - give TRH
For FSH/LH - give GnRH

Radiological analysis - can spot apoplexy (haemorrhage/infarction); adenoma; empty sella turcica

Question 8

Sheehan’s syndrome is

Answer 8

Postpartum ypopituitarism specific in women

Question 9

Sheehan’s syndrome is caused by

Answer 9

Post-partum haemorrhage –> hypovolaemic shock and blood loss.

Leads to pituitary infarction
Blood loss in the vasoconstrictor spasm of hypophyseal arteries and this leads to:
- Ischaemia of the pituitary (which is enlarged during pregnancy due to lactotroph hyperplasia).
- Necrosis of the pituitary

Question 10

Panhypopituitarism will occur in adults with …

Answer 10

progressive loss of pituitary secretion

Question 11

3 main types of Panhypopituitarism

Answer 11

• Simmond’s Disease
• Sheehan’s Syndrome
• Pituitary Apoplexy

Question 12

Presentation of Sheehan’s is

Answer 12

fast

Question 13

Presentation of Pituitary apoplexy is

Answer 13

fast

in pituitary adenoma

Question 14

Pituitary apoplexy is

Caused by

Answer 14

Similar to Sheehan’s but not specific to women

Intra-Pituitary infarction / haemorrhage

Question 15

Pituitary apoplexy - there is rapid presentation in

Answer 15

patients with pre-existing pituitary tumours which suddenly infarct

Question 16

A deficiency in a single adenohypophysial hormone results in

Answer 16

secondary endocrine gland failure

Question 17

Examples of secondary endocrine gland failure:
o Gonadotrophin ­
o Thyrotrophin
o Corticotrophin

Answer 17

-Hypogonadism
-­Hypothyroidism
­‐Hypoadrenocorticalism

Question 18

Signs and symptoms of panhypopituitarism

Answer 18

decreased FSH/LH - secondary hypogonadism - secondary amenorrhoea, decreased libido, erectile dysfunction

decreased ACTH - secondary hypoadrenalism - fatigue

decreased TSH - secondary hypothyroidism - fatigue, weight gain

Question 19

Signs and symptoms of Sheehan’s syndrome

Answer 19

lethargy
anorexia
weight loss
no lactation
don't resume menses

Question 20

Signs and symptoms of pituitary apoplexy

Answer 20

severe sudden headache
bitemporal hemianopia - pressed onto the optic chasm
diplopia
ptosis

Question 21

Hormone replacement therapy and how to check for
ACTH
TSH
Women LH/FSH
Men LH/FSH
GH

Answer 21

ACTH - hydrocortisone. Check serum cortisol.

TSH - thyroxine. Check serum free T4.

Women LH/FSH. HRT (E+P). Check by alleviation of symptoms and bleeds

Men LH/FSH. Testosterone. Check by alleviation of symptoms and serum testosterone

GH - GH. Check IGF-1/ growth chart for children.

Question 22

Endocrine causes of short stature

Answer 22

Lack of GH (pituitary dwarfism)
Cushing’s
Hypothyroidism
Poorly controlled T1DM

Question 23

Non endocrine causes of short stature

Answer 23

genetic - down's, turner's, Prader Willi
Emotional deprivation
Malnutrition/ malabsorption 
systemic disease
Skeletal dysplasia e.g. achondroplasia/ Osteogenesis I

Question 24

Describe the growth axis

Answer 24

hypothalamus –> adenohypophysis –> GHRH –> GH –> target tissues / liver –> IGF I –> target tissues

Question 25

Diagnosis of short stature

Answer 25

Growth chart of mid parental height

GH provocation test, giving:

• GHRH and arginine IV
• insulin IV – hypoglycaemia
• Glucagon IM
• Exercise

Measure plasma GH (no response). Low plasma IGF-1

Question 26

whereabouts of the growth axis is affected with:
PW syndrome
Pituitary dwarfism
Laron dwarfism

Answer 26

PW — GH deficiency caused by hypothalamus dysfunction

Pituitary dwarfism — childhood lack of GH produced from pituitary

Laron dwarfism — GH receptor defect (on liver) so IGF-I not produced

Question 27

Treatment

Answer 27

Somatotrophin given 4/5x per week

Question 28

Signs of GH deficiency in adults

Answer 28

increased adiposity 
increased waist:hip ratio
decreased muscle
decreased HDL
increased LDL
decreased psychological wellbeing

Question 29

pros and cons of therapy in adults

Answer 29

+ reverse signs + increases bone density

- increased risk of CVS effects - increased soft tissue growth (cardiomegaly) - increased risk of cancer