Hyposecretion of anterior pituitary hormones

Question 1

What is primary endocrine gland disease?

Answer 1

When it caused by disorder of the endocrine gland

Question 2

What is secondary endocrine gland disease?

Answer 2

When it is caused by disorder of the anterior pituitary

Question 3

What is tertiary endocrine gland disease?

Answer 3

When it is caused by disorder of the hypothalamus

Question 4

What is panhypopituitarism?

Answer 4

Decreased production of all anterior pituitary hormones

Question 5

How can panhypopituitarism be acquired? (6)

Answer 5

Tumours- hypothalamic and pituitary
Radiation- damage
Infection- meningitis
Traumatic brain injury
Infiltrative disease
Inflammatory

Question 6

How else can panhypopituitarism be caused?

Answer 6

Congenital (rare) or mutations (very rare)

Question 7

How does panhypopituitarism usually develop?

Answer 7

In an adult with progressive loss of pituitary secretion>

Question 8

What is the normal order of pituitary secretion loss?

Answer 8

Gonadotrophins
GH
Thyrotrophin
Corticotrophin

Question 9

What are the three main types of panhypopituitarism?

Answer 9

Simmond’s disease
Sheehan’s syndrome
Pituitary apoplexy

Question 10

What is the onset of Simmond’s like?

Answer 10

Insidious- very slow

Question 11

What are the causes of Simmond’s? (5)

Answer 11

Infiltrative processes
Pituitary adenomas
Craniopharyngiomas
Cranial injury
Post surgery

Question 12

What are the symptoms of Simmond’s mainly due to?

Answer 12

Loss of thyroidal, gonadal and adrenal function

Question 13

What are the symptoms of Simmond’s?

Answer 13

Secondary amenorrhoea
Impotence
Loss of libido
Tiredness
Waxy skin
Loss of body hair
Hypotension

Question 14

What is different about Sheehan’s compared to the other two?

Answer 14

It is specific to women

Question 15

How does Sheehan’s develop?

Answer 15

Develops acutely following postpartum haemorrhage resulting in pituitary infarction

Question 16

How does the postpartum haemorrhage lead to pituitary infarction?

Answer 16

The blood loss results in vasoconstrictor spasm of the hypophysial arteries and this leads to ischaemia and necrosis of the pituitary

Question 17

How does Sheehans and pituitary apoplexy compare?

Answer 17

Very similar but pituitary apoplexy is in men and women and just due to normal haemorrhages

Question 18

How do you diagnose hypopituitarism?

Answer 18

You can’t measure hypothalamic hormones so you measure basal values of the plasma for pituitary or target endocrine gland hormones

Question 19

Why will a single measurement not suffice?

Answer 19

Hypothalamic hormones are released in pulses

Question 20

What test can you use to find out if a person is producing hormones at a normal level?

Answer 20

Stimulation test

Question 21

What does a lack of somatotrophin cause in children and adults?

Answer 21

Pituitary dwarfism in children

Effects uncertain in adults

Question 22

What are other causes of short stature in children? (6)

Answer 22

Genetic- Down's, Turner's, Prader Willi
Malnutrition
Emotional deprivation
Systemic disease
Malabsorption
Endocrine disorders- Cushing's, hypothyroidism, GH deficiency

Question 23

What are the acquired causes of GH deficiency in children? (6)

Answer 23

Tumours of the hypothalamus or pituitary
Other intercranial tumours nearby (optic nerve glioma)
Irradiation
Head injury
Infection or inflammation
Severe psychosocial deprivation

Question 24

What are the genetic causes of GH deficiency in children?

Answer 24

Congenital (rare) - Deficiency of hypothalamic GHRH
Mutations of the GH gene (very rare)
Developmental abnormalities

Question 25

What controls GH at a hypothalamic level?

Answer 25

GHRH and somatostatin

Question 26

What are most endocrine-related causes of short stature due to?

Answer 26

Decreased production of GHRH

Question 27

What does GH stimulate the production of in the liver?

Answer 27

IGF-1 (insulin like growth factor) (liver is main source but is produced in many places)

Question 28

What does IGF-1 do?

Answer 28

Mediate growth effects

Question 29

What is laron dwarfism due to?

Answer 29

GH receptor defect

Question 30

Explain how GH receptor defect leads to Laron dwarfism?

Answer 30

As a result IGF-1 levels are low as somatotrophin isn't having an effect

Question 31

What is the main presentation of Kallmann's syndrome?

Answer 31

Hypogonadism and anosmia

Question 32

What is Kallmann's caused by?

Answer 32

Genetic defect where the neurones in the embryo that will go on to produce GnRH are unable to migrate to the hypothalamus so their hypothalamus lacks GnRH neurones

Question 33

What other condition leads to hypogonadism and is a hypothalamic defect?

Answer 33

Prader Willi

Question 34

What is the standard way of testing the ability of the pituitary to produce GH?

Answer 34

Stimulate GH production by inducing hypoglycaemia (The gold standard is insulin induced hypoglycaemia)

Question 35

What is the main aim of pituitary deficiency treatment?

Answer 35

Restore homeostasis by replacing missing hormones

Question 36

What does growth hormone therapy lead to in children?

Answer 36

Acceleration of linear growth | Decreased body fat

Question 37

Which children respond better to growth hormone therapy?

Answer 37

Young and obese

Question 38

What is a common problem with GH therapy?

Answer 38

They develop resistance (antibodies)

Question 39

How is growth hormone therapy administered?

Answer 39

Subcutaneous or intramuscular

Question 40

When is GH administered?

Answer 40

Daily- In the afternoon as levels are normally high at night anyway

Question 41

What is the half life of GH like?

Answer 41

Short- 20 mins

Question 42

What does GH work on hence what is its action duration like?

Answer 42

Protein synthesis so long

Question 43

What are the adverse effects of GH?

Answer 43

Lipoatrophy at site of injection Intracranial hypertension- headaches Increased risk of cancer

Question 44

What are the signs and symptoms of GH deficiency in adults?

Answer 44

``` Reduced lean mass Increased adiposity Increased waist:hip ratio Reduced muscle strength and bulk Decreased HDL and increased LDL Impaired psychological wellbeing ```

Question 45

What are the 4 ways of diagnosing GH deficiency in adults?

Answer 45

Lack of response to GH stimulation test GHRH and Arginine Low plasma IGF-1 Low plasma IGF-BP3