Clinical Abnormalities of Glands

Question 1

What is hyper-

Answer 1

Hormone over secretion

Question 2

What is hypo-

Answer 2

Hormone under secretion

Question 3

What is primary in relation to hyper-

Answer 3

Too much hormone coming from gland itself

Question 4

What is secondary in relation to hyper-

Answer 4

One gland secretes too much of the hormone that controls the other gland, make it overactive

Question 5

What is primary in relation to hypo-

Answer 5

Too little hormone coming from gland itself

Question 6

What is secondary in relation to hypo-

Answer 6

One gland secretes too little of the hormone that controls the other gland, making it underactive

Question 7

How can tumours affect glands?

Answer 7

Can destroy the gland and cause underactive gland (often occurs in pituitary, compresses tissue as cannot expand)

Question 8

What is over-secretion usually caused by?

Answer 8

Usually benign tumours

Question 9

What is under-secretion usually caused by?

Answer 9

Gland destruction due to:

• Inflammation (including autoimmune)
• Infarction (blood supply stops and tissue dies)

Question 10

How can tumours/nodules contribute to endocrine gland diseases?

Answer 10

Have hormone production

Question 11

What is prolactin over-secretion caused by?

Answer 11

• Usually due to a pituitary tumour secreting prolactin (prolactinoma)
• Can be due to a tumour sitting between pituitary gland and hypothalamus, suppressing the interaction between the two. Prolactin levels increase as no inhibitory effect

Question 12

What is the clinical presentation of prolactin over-secretion?

Answer 12

• Galactorrhoea (breast milk production)
• Amenorrhoea (periods stop in women, sexual dysfunction in men)
• Headaches and visual field problems in large tumours

Question 13

How can you diagnose prolactin over-secretion?

Answer 13

Use a static test

Question 14

What can mildly raised prolactin be due to?

Answer 14

1. Sex (nipple stimulation)
2. Stress
3. Drugs (antipsychotics and antidepressants)
4. Non-functioning pituitary tumours

Question 15

How do non-functioning pituitary tumours cause mildly raised prolactin?

Answer 15

Compress the hypothalamus and interfere with the inhibitory effect on prolactin secretion

Question 16

How can prolactinomas be treated?

Answer 16

Are the only over-secreting pituitary tumour that can be treated medically (rarely require surgical intervention)

Question 17

What is consequence of GH over-secretion in children?

Answer 17

1. Excessive growth spurt
2. Increased size of hands and feet
3. If left untreated, can lead to gigantism

Question 18

What is consequence of GH over-secretion in adults?

Answer 18

1. Affects skin, soft tissue and skeleton (acromegaly)
2. Increased sweating
3. Wide and large hands/feet

Question 19

How can you diagnose GH over-secretion?

Answer 19

Suppression test is necessary:

1. Glucose is given
2. GH measurements taken at different times
3. In healthy people, glucose suppresses GH production

Question 20

How can presence of pituitary tumour be confirmed?

Answer 20

MRI (imaging)

Question 21

How can tumour causing GH over-secretion be treated?

Answer 21

Surgical removal of tumour. Radiotherapy and medical therapy may also be needed as surgery doesn’t always remove whole tumour

Question 22

What are the clinical presentations of Cushing’s syndrome?

Answer 22

1. Growth arrest in children
2. Round, moon-like face
3. Acne
4. Hirsutism (growth of hair on woman’s face and body)
5. Fat redistribution - truncal obesity and thin extremities
6. Thin skin and easy bruising
7. Striae on abdomen

Question 23

What are the complications of Cushing’s syndrome?

Answer 23

1. Hypertension
2. Diabetes mellitus
3. High risk of infections
4. Poor wound healing

Question 24

What is treatment for pituitary and adrenal related Cushing’s?

Answer 24

Surgery (radiotherapy and medical treatment may also be required)

Question 25

What is treatment for cancer related Cushing's?

Answer 25

Treat original cancer

Question 26

What is Cushing's syndrome?

Answer 26

Condition caused by excess production of cortisol in the body, regardless of the cause

Question 27

What is Cushing's disease?

Answer 27

When Cushing's syndrome is caused by pituitary tumour secreting excess amounts of ACTH

Question 28

What's the most common cause of Cushing's syndrome?

Answer 28

Pituitary tumour secreting ACTH (Cushing's disease)

Question 29

What are the other causes of Cushing's syndrome?

Answer 29

- Non pituitary tumours that produce ACTH (ectopic) e.g. lungs - Benign or malignant tumours of the adrenal gland which produce excess cortisol leading to low ACTH levels (negative feedback)

Question 30

What test can be used to diagnose Cushing's?

Answer 30

Suppression test using dexamethasone

Question 31

What is dexamethasone?

Answer 31

Man-made steroid similar to cortisol that is used to confirm the failure of cortisol production

Question 32

What is the effect of dexamethasone in normal people?

Answer 32

Reduces ACTH release (negative feedback), therefore reducing cortisol

Question 33

What are the 2 types of dexamethasone tests?

Answer 33

Low-dose and high-dose

Question 34

What are results of dexamethasone test in Cushing's syndrome caused by pituitary tumours (Cushing's disease) or cancers?

Answer 34

Low dose test - No decrease in blood cortisol - Detectable/high ACTH High dose test - Decrease in blood cortisol as production of ACTH by pituitary adenomas usually suppressed

Question 35

What are results of dexamethasone test in Cushing's syndrome caused by adrenal tumour?

Answer 35

Low dose test - No decrease in blood cortisol - Low/undetectable ACTH