Hyperthyroidism

Question 1

Which is more common, primary or secondary hyperthyroidism?

Answer 1

Primary

Secondary is very rare

Question 2

Is primary hyperthyroidism more common in men or women?

Answer 2

10 times more common in women, present in 2% of the population

Question 3

What is the normal action of the thyroid gland as cause by the hypothalamus?

Answer 3

Hypothalamus secretes TRH (thyrotypin releasing hormone), which stimulates anterior pituitary to produce TSH (thyroid stimulating hormone), which stimulates the thyroid to pdocue T3 and T4.

Question 4

Are patients with primary hypothyroidism given T3 or T4? Why?

Answer 4

T4 because it has a longer half life and does not cause symptoms of hyperthyroidism e.g. tachycardia

Question 5

What is the main cause of hyperthyroidism?

Answer 5

Thyroid autoimmunity

Question 6

What is Grave’s disease?

Answer 6

An autoimmune - antibodies are produced in the body that mimic TSH so the thyroid is always stimulated. Usually triggered by a viral infection.

Question 7

Give the 5 causes of hyperthyroidism?

Answer 7

Grave’s disease
Toxic nodule or toxic multi nodule goitre (rarely cancerous)
Thyroiditis (inflammation/destruction)
Drug induced (usually contains a lot of iodine)
Rarities

Question 8

How does thyroiditis cause hyperthyroidism?

Answer 8

Inflammation or destruction of the thyroid causes release of thyroid hormone, followed by a period of hypothyroidism while the gland repairs itself. Followed by recovery and normal function.

Question 9

Give some examples of clinical presentation of hyperthyroidism

Answer 9

Hyperactivity, insomnia, irritability, heat intolerance, sweating, palpitations/tachycardia, weight loss, menstrual problems, hand tremor, fast pulse

Thyroid will be enlarged

Question 10

How can the thyroid’s appearance help diagnose the cause of hyperthyroidism?

Answer 10

It will usually be enlarged
Smooth = Graves’ disease
Nodular = toxic nodules
Tender = thyroid inflammation

Question 11

How many cases of hyperthyroidism are cased by Grave’s disease?

Answer 11

80%

Question 12

What signs are present in Graves’ disease that are not in other hyperthyroidisms?

Answer 12

Thyroid eye disease:
Swelling round eyes, profusion of eyeball, paralysis of eye muscles,
lid lag

Fat around the eyes becomes inflamed and water is trapped

Question 13

How can Grave’s disease be diagnosed?

Answer 13

Thyroid blood test for raised thyroid hormone and suppressed TSH

Question 14

How can Graves’ disease be treated?

Answer 14

Anti-Thyroid drugs cause remission in 50% of patients after 6-18 months (50% will relapse and need different treatment)
Radioactive iodine destroys the thyroid gland
Surgery

Question 15

Why can anti-thyroid drugs be dangerous?

Answer 15

Can suppress white cell production (very rare)

Question 16

What does growth hormone deficiency cause in children and adults?

Answer 16

Children; failure of growth

Adults; tiredness, depression, no symptoms

Question 17

How is GH deficiency tested?

Answer 17

glucagon stimulation test or insulin stress test

Question 18

How can GH deficiency be treated?

Answer 18

Injections, but very expensive

Question 19

What can cause steroid under-secretion?

Answer 19

Adrenal or pituitary failure

Question 20

What are the clinical presentations of steroid under-secretion?

Answer 20

Failure to grow in children
tiredness
dizziness
abdominal pain
vomiting and diarrhoea

Question 21

How can steroid under-secretion be diagnosed?

Answer 21

A stimulation test
Either the Synacthen test (giving ACTH) if primary adrenal failure is suspected, or glucagon stimulation test (GST)
OR insulin stress test if secondary adrenal failure is suspected

Question 22

How can steroid under-secretion be treated?

Answer 22

Tablets to replace the missing hormone

Question 23

How serious is steroid under-secretion?

Answer 23

Can be fatal

Cortisol should be given whenever suspected

Question 24

In which group of people is primary hypothyroidism most common?

Answer 24

Older ladies

Question 25

What is secondary hypothyroidism usually caused by?

Answer 25

Complete pituitary failure

Question 26

How is hypothyroidism treated?

Answer 26

Cheap hormone replacement tablets

Question 27

What are the signs and symptoms of severe hypothyroidism?

Answer 27

Weakness and dry skin,
sensation of cold and decreased sweating,
impaired memory
constipation
weight gain
hair loss

Question 28

What is primary sex hormone deficiency caused by?

Answer 28

Males = testicular failure

Females = ovarian failure

Question 29

What does sex hormone deficiency cause?

Answer 29

Males = erectile dysfunction, reduced libido
Females = menstrual abnormalities/amenorrhoea

Question 30

Give some causes of amenorrhoea

Answer 30

Uterine problems
ovarian problems
pituitary problems
hypothalamic problems
pregnancy!!

Question 31

How is sex hormone deficiency diagnosed?

Answer 31

Static test for testosterone, oestradiol, FSH, LH

Question 32

How is sex hormone deficiency treated?

Answer 32

Hormone replacement therapy

Pituitary hormone replacement

Question 33

What are the potential causes of pituitary failure?

Answer 33

Large tumour which compresses and kills the gland so no hormones are secreted
Infarction (obstruction of blood supply)
Other causes

Question 34

How is pituitary failure diagnosed?

Answer 34

A combination of static and stimulatory tests as it usually involves multiple hormones

Question 35

When should an MRI be carried out when diagnosing pituitary failure?

Answer 35

At the end, after static and dynamic tests and done first

Question 36

What can cause parathyroid hormone increase? (not under pituitary control)

Answer 36

Cancer
Primary hyperparathyroidism
Drugs
Other causes

Question 37

What are the symptoms of hypercalcaemia?

Answer 37

thirst, passing too much urine, constipation, abdominal pain