20 Thyroid Disorders

Question 1

What is goitre?

Answer 1

Enlargement of thyroid gland

Question 2

What causes goitre?

Answer 2

Overstimulated thyroid gland- due to HYPO or HYPER -thyroidism

Question 3

What are the possible causes of HYPOTHYROIDISM?

Answer 3

1) Failure of thyroid gland
2) TSH/TRH deficiency
3) Inadequate dietary iodine supply
4) Radioactive iodine
5) Autoimmunity(e.g. Hashimoto’s)
6) Post surgery
7) Congenital
8) Anti-thyroid drugs

Question 4

What are the symptoms of hypothyroidism?

Answer 4

• Obesity
• Lethargy
• Intolerance to cold
• Bradycardia
• Dry skin
• Alopecia
• Hoarse voice
• Constipation
• Slow reflexes (Low T3,4 + elevated TSH)
• Myxedema
• Cretinism (infants)

Question 5

How does cretinism present in infants?

Answer 5

Dwarfed stature, mental deficiency, poor bone development, slow pulse, muscle weakness, GI disturbances

Question 6

=How does myxoedema present in adults?

Answer 6

Thick puffy skin, muscle weakness, slow speech, mental deterioration

Question 7

What is Hashimoto’s disease?

Answer 7

Autoimmune disease- thyroid follicle destruction- hypothyroidism. 5x more common in women than men

Question 8

=How should Hashimoto’s be treated?

Answer 8

=Oral thyroid hormone (T4 as longer half life) (needs to be very carefully controlled otherwise risk of hyperthyroidism- risk of stroke and osteoporosis)

Question 9

What causes hyperthyroidism?

Answer 9

1) Autoimmune (Graves’ disease) 2) Toxic multinodular goitre 3) Solitary toxic adenoma 4) Excessive T4 (/T3) therapy 5) Drugs- amiodarone (anti arrythmatic medication) 6) Ectopic thyroid tissue

Question 10

=What are some signs of hyperthyroidism?

Answer 10

Goitre, Bulging eyes

Question 11

What are the symptoms of hyperthyroidism?

Answer 11

Weight loss, irritability, heat intolerance, sweating, tackycardia, fatigue, weakness, increased bowel movement, increased appetite, possible tremor, hyper-reflexive, loss of libido, sweating and tremor

Question 12

=What is Graves’ disease?

Answer 12

Autoimmune disease- hyperthyroidism- production of TSI (Thyroid stimulating immunoglobulin)- continuously stimulates Thyroid hormone secretion- outside normal negative feedback control

Question 13

=What is thyroid scintigraphy?

Answer 13

Technetium-99m used for isotope scanning- with gamma camera- shows activity of thyroid

Question 14

=How to antithyroid drugs work? Give an example.

Answer 14

Block formation of thyroid hormone. CARBIMAZOLE- prevents thyroid peroxidase coupling and iodinating tyrosine and thyroglobulin

Question 15

=What tests are done to assess the thyroid?

Answer 15

Ultrasound, radio-isotope, Plain x-ray, CT scan