THYROID DISORDERS

Question 1

Thyroid hormones

Answer 1

• The amount of circulating thyroid hormones is regulated by a NEGATIVE FEEDBACK LOOP
• High levels of T3 and T4 = suppress the function/production of TSH or TRH = inhibit their own production

Question 2

TRH

Answer 2

Thyrotropin-releasing hormone produced by the hypothalamus

Question 3

TSH

Answer 3

Thyroid stimulating hormones

Question 4

High T3 and T4

Answer 4

= low TSH

Question 5

What are the biomarkers of hyperthyroidism?

Answer 5

High T3 and T4
Low TSH

Question 6

Symptoms of hyperthyroidism

Answer 6

• Hyperactivity
• Insomnia
• Heat Intolerance
• Increased Appetite
• Weight Loss
• Diarrhoea
• Goitre
  INCREASED METABOLISM AND ACTIVITY

Question 7

Hyperthyroidism treatment

Answer 7

1. Carbimazole
2. Propylthiouracil

Beta blockers can be used to help with symptomatic relief

Question 8

MHRA guidance: carbimazole

Answer 8

• Neutropenia and Agranulocytosis → report sore throat, malaise, fever
• Congenital Malformations → women use contraception during treatment
• Acute Pancreatitis → report and stop immediately if develop signs of severe abdominal pain

Question 9

Propythiouracil side effects

Answer 9

Be cautious of liver disorder:
- jaundice
- dark urine
- nausea

Question 10

Grave’s disease

Answer 10

autoimmune disorder
immune system attacks the thyroid gland, causing it to become overactive
too much T3 and T4

Question 11

Grave’s disease treatment

Answer 11

1. Radioactive iodine
   - If remission likely to be achieved with anti-thyroids, can consider carbimazole
   - Use carbimazole if iodine or surgery CI- given as a block and replace regimen in combo with levothyroxine for 12-18 months

Question 12

Block and replace regimen

Answer 12

Combination of fixed high dose carbimazole with levothyroxine

Question 13

Hyperthyroidism in pregnancy

Answer 13

1st trimester - propylthiouracil (due to carbimazole’s congenital defects
2nd + 3rd trimester - carbimazole (due to propylthiouracil’s hepatotoxicity)

Question 14

What drug is preferred for hyperthyroidism in history of pancreatitis

Answer 14

Propylthiouracil

Question 15

Hypothyroidism biomarkers

Answer 15

Low T3 and T4
High TSH

Question 16

Symptoms of hypothyroidism

Answer 16

• Fatigue
• Weight Gain
• Constipation
• Depression
• Dry Skin
• Intolerance to Cold
• Menstrual Irregularities
• Decreased metabolism and activity

Question 17

Hypothyroidism treatment

Answer 17

1. Levothyroxine

Question 18

Levothyroxine monitoring

Answer 18

Monitor TSH: Every 3 months until stable, then yearly thereafter

Question 19

Levothyroxine counselling

Answer 19

Take medicine in the morning, at least 30 minutes before having breakfast or caffeinated drinks

Question 20

MHRA guidance about levothyroxine brands

Answer 20

MHRA: New guidance that a small proportion of patients can feel symptoms if alternating between brands

Question 21

Liothyronine

Answer 21

More rapid and potent output (20-25mcg - 100mcg of levothyroxine)
Non-UK brands may not be bioequivalent