clinical thyroid disease - hypothyroidism

Question 1

What are the three main parts of the thyroid gland

Answer 1

Right lobe, left lobe and the isthmus

Question 2

How is the release of T3 and T4 stimulated

Answer 2

TRH is released from the hypothalamus and travels to the anterior pituitary where it stimulates the release of TSH which then goes to the thyroid gland and stimulates the release of T3 and T4

Question 3

What causes the negative feedback in the release of T3 and T4

Answer 3

T3 and T4 on the anterior pituitary and the hypothalamus

Question 4

What is the normal TSH level

Answer 4

0.35-4.5

Question 5

What are the symptoms of hypothyroidism

Answer 5

Fatigue/lethargy
Cold intolerance
weight gain
weakness, arthralgia and myalgia
constipation
irregularities in menstruation
depression
dry skin and reduced hair
thyroid pain

Question 6

What are the signs of hypothyroidism that are seen on examination

Answer 6

Course dry skin/ hair and hair loss
Oedema including swelling of the eye balls and puffy face
Hoarseness in the voice or deepening
Goitre
Bradycardia and diastolic hypertension
Delayed relaxation of deep tendon reflexes
Paraesthesia caused by carpal tunnel

Question 7

What is carpal tunnel syndrome

Answer 7

Pressure on the nerves in the wrist that can cause paraesthesia and numbness in the hands and fingertips

Question 8

What tests are done for hypothyroidism suspicion

Answer 8

Bloods :
TFT - thyroid function tests - T4 and TSH
Full blood count
HbA1c - to check for diabetes

Question 9

Which gender is hypothyroidism more common in

Answer 9

Women

Question 10

What are the congenital causes of of hypithyroidism

Answer 10

Agenesis / maldevelopment

Issues with production of hormones

Question 11

What is the most common cause of primary hypothyroidism

Answer 11

Hashimatos autoimmune thyroid disease

Question 12

What drugs can cause primary hypothyroidism

Answer 12

Antithyroid drugs, amiodarone, lithium and interferon

Question 13

What is the link between iodine and hypothyroidism

Answer 13

Chronic iodine deficiency can cause hypothyroidism - iodine is required for the production of T3 and T4

Question 14

What are causes of secondary.tertiary hypothyroidism

Answer 14

Pituitary tumour
Craniopharyngioma
Post pituitary surgery or radiotheraoy

Question 15

What is the treatment for hypothyroidism in adults less than 65

Answer 15

Start levothyroxine at 1.6micrograms per kg per day

Question 16

What is the treatment for adults more than 65 years of age or with pre-existing cardiac disease

Answer 16

Levothyroxine - 25-50 micrograms a day

Question 17

What presents with High TSH and a normal T4

Answer 17

Subclinical hypothyroidism

Question 18

What presents with a high TSH and a low T3/T4

Answer 18

Hypothyroidism

Question 19

What is the treatment fir subclinical hypothyroidism

Answer 19

If there is raised TSH, treat as if it is hypothyroidism