Thyroid Therapeutics

Question 1

Draw and label the anatomy of the thyroid and parathyroid glands.

Answer 1

Refer to Slide 3 in Thyroid & Parathyroid Glands

Question 2

What does the thyroid gland consist of?

Answer 2

• Two lobes lateral to the trachea
  – Isthmus
  – Follicles (follicle cells surrounding colloid)
  – Parafollicular cells (C cells)
  
  • Secrete calcitonin.

Question 3

What is the function of the thyroid gland?

Answer 3

• Regulation of thyroid hormone secretion
  
  • Thyrotropin-releasing hormone (TRH)
  • Thyroid stimulating hormone (TSH)

Question 4

What are examples of thyroid hormones?

Answer 4

90% T4 and 10% T3

Question 5

Explain the main function of thyroid hormones.

Answer 5

• Bound to thyroxine-binding globulin, thyroxine-binding pre-albumin, or albumin
• Affect tissue growth and maturation,
• Cell metabolism
• Heat production
• Oxygen consumption

Question 6

Where are parathyroid glands located?

Answer 6

• Behind the upper and lower poles of the thyroid gland.

Question 7

Explain the function of parathyroid glands.

Answer 7

Produces parathyroid hormone (PTH).
- Serum Calcium Regulator
- Calcitonin Antagonist

Question 8

Explain how parathyroid glands helps regulate calcium levels.

Answer 8

1. If there’s a slight decrease in serum calcium
2. Increases the PTH secretion - this can be triggered by substances that increase the cAMP levels or hypermagnesemia.
3. PTH acts on bone, kidney and gut.
4. Increase in serum calcium levels
5. Lowered PTH secretion - also can be triggered by triggered by substances that decrease the cAMP levels or hypomagnesemia.

Question 9

Draw and label the diagrams that represents the function of parathyroid glands.

Answer 9

Refer to Slides 11 and 12 from the Thyroid and Parathyroid Glands lecture.

Question 10

What are the different types of hyperparathyroidism?

Answer 10

• Primary Hyperparathyroidism
• Secondary Hyperparathyroidism

Question 11

What is primary hyperparathyroidism?

Answer 11

Excess PTH secretion from one or more parathyroid glands.

Question 12

What is secondary hyperparathyroidism?

Answer 12

Increase in PTH secondary to a chronic disease.

Question 13

What is hypoparathyroidism?

Answer 13

Abnormally low PTH levels.

Question 14

What is the main cause of hypoparathyroidism?

Answer 14

Parathyroid damage in thyroid surgery.

Question 15

Explain the effects of hyperparathyroidism.

Answer 15

• Increase in the PTH production due to a benign growth of 1:4 parathyroid glands.
• Induces abnormally high serum Ca2+ levels
• Bone decalcification
• Kidney Stones Development

Question 16

What are the signs and symptoms of hyperparathyroidism?

Answer 16

• Fatigue
• Apathy
• Muscle weakness
• Vomiting
• Hypertension
• Demineralisation of bones
• Development of kidney stones

Question 17

What is hypercalcaemic crisis?

Answer 17

Acute hypercalcemic crisis can occur with calcium levels over 15 mg/dl (3.75mmol/L).

Question 18

What type of symptoms would you expect to see in patients with suspected hypercalcaemic crisis?

Answer 18

• Neurological
• CV
• Renal

Question 19

What treatment options are available for hypercalcaemic crisis?

Answer 19

– IV fluids
– Phosphate therapy
– Calcitonin
– Dialysis

Question 20

What is the main cause of hypoparathyroidism?

Answer 20

• Usually due to accidental removal of parathyroid glands during thyroid surgery.

Question 21

Explain how the symptoms occur for hypoparathyroidism.

Answer 21

• Hypocalcemiaa
• Hyperphosphatemia

Question 22

What are the signs and symptoms of hypoparathyroidism?

Answer 22

– Neuromuscular irritability -> Tetany (intermittent muscle spasms)
- Numbness, tingling, cramps -> Bronchospasm, laryngeal spasm, carpopedal spasm.

Question 23

What is the treatment option for Hypoparathyroidism?

Answer 23

Calcium Gluconate at bedside

Question 24

Explain how thyroid hormones are made.

Answer 24

Refer to Slide 18 and 19.

Question 25

What are the 3 major thyroid-binding proteins?

Answer 25

1. Thyroid Hormone-binding Globulin (TBG):
   
   • Carries 70% T3 & T4
2. Thyroxine-binding prealbumin (TBPA):
   
   • Binds approximately 10% of circulating T4 and lesser amounts of T3
3. Albumin:
   – Binds approximately 15% of circulating T4 and T3

Question 26

Draw and label diagrams associated with thyroid-binding protein function.

Answer 26

Refer to slide 21 + 22.

Question 27

Where are thyroid hormones secreted?

Question 28

Explain the effect of thyroid hormones when released.

Question 29

Which type of drugs can suppress TSH secretion?

Question 30

Explain the general relationship between TSH release, dopamine, somatostatin and glucocorticoids.

Question 31

What type of thyroid-binding protein are most of the thyroid hormone (T3 & T4) bound to?

Question 32

Explain the mechanism of action of T3 and T4 hormones.

Question 33

Explain the major functions of thyroid hormones.

Question 34

Draw and label the diagram for thyroid hormone secretion regulation.

Question 35

What are the effects of hypothyroidism?

Question 36

What are the effects of hyperthyroidism?

Question 37

Give examples of thyroid disorders associated with hyperthyroidism.

Question 38

What is Graves’ Disease?

Question 39

What are the main characteristics of Graves’ Disease?

Question 40

Draw and label the diagram that represents the effects of Graves’ Disease.

Question 41

What are the manifestations of Thyroid Storm?