Thyroid Therapeutics Flashcards
Thyroid & Parathyroid Glands by Praveen
Draw and label the anatomy of the thyroid and parathyroid glands.
Refer to Slide 3 in Thyroid & Parathyroid Glands
What does the thyroid gland consist of?
- Two lobes lateral to the trachea
– Isthmus
– Follicles (follicle cells surrounding colloid)
– Parafollicular cells (C cells)- Secrete calcitonin.
What is the function of the thyroid gland?
- Regulation of thyroid hormone secretion
- Thyrotropin-releasing hormone (TRH)
- Thyroid stimulating hormone (TSH)
What are examples of thyroid hormones?
90% T4 and 10% T3
Explain the main function of thyroid hormones.
- Bound to thyroxine-binding globulin, thyroxine-binding pre-albumin, or albumin
- Affect tissue growth and maturation,
- Cell metabolism
- Heat production
- Oxygen consumption
Where are parathyroid glands located?
- Behind the upper and lower poles of the thyroid gland.
Explain the function of parathyroid glands.
Produces parathyroid hormone (PTH).
- Serum Calcium Regulator
- Calcitonin Antagonist
Explain how parathyroid glands helps regulate calcium levels.
- If there’s a slight decrease in serum calcium
- Increases the PTH secretion - this can be triggered by substances that increase the cAMP levels or hypermagnesemia.
- PTH acts on bone, kidney and gut.
- Increase in serum calcium levels
- Lowered PTH secretion - also can be triggered by triggered by substances that decrease the cAMP levels or hypomagnesemia.
Draw and label the diagrams that represents the function of parathyroid glands.
Refer to Slides 11 and 12 from the Thyroid and Parathyroid Glands lecture.
What are the different types of hyperparathyroidism?
- Primary Hyperparathyroidism
- Secondary Hyperparathyroidism
What is primary hyperparathyroidism?
Excess PTH secretion from one or more parathyroid glands.
What is secondary hyperparathyroidism?
Increase in PTH secondary to a chronic disease.
What is hypoparathyroidism?
Abnormally low PTH levels.
What is the main cause of hypoparathyroidism?
Parathyroid damage in thyroid surgery.
Explain the effects of hyperparathyroidism.
- 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
What are the signs and symptoms of hyperparathyroidism?
- Fatigue
- Apathy
- Muscle weakness
- Vomiting
- Hypertension
- Demineralisation of bones
- Development of kidney stones
What is hypercalcaemic crisis?
Acute hypercalcemic crisis can occur with calcium levels over 15 mg/dl (3.75mmol/L).
What type of symptoms would you expect to see in patients with suspected hypercalcaemic crisis?
- Neurological
- CV
- Renal
What treatment options are available for hypercalcaemic crisis?
– IV fluids
– Phosphate therapy
– Calcitonin
– Dialysis
What is the main cause of hypoparathyroidism?
- Usually due to accidental removal of parathyroid glands during thyroid surgery.
Explain how the symptoms occur for hypoparathyroidism.
- Hypocalcemiaa
- Hyperphosphatemia
What are the signs and symptoms of hypoparathyroidism?
– Neuromuscular irritability -> Tetany (intermittent muscle spasms)
- Numbness, tingling, cramps -> Bronchospasm, laryngeal spasm, carpopedal spasm.
What is the treatment option for Hypoparathyroidism?
Calcium Gluconate at bedside
Explain how thyroid hormones are made.
Refer to Slide 18 and 19.
What are the 3 major thyroid-binding proteins?
- Thyroid Hormone-binding Globulin (TBG):
- Carries 70% T3 & T4
- Thyroxine-binding prealbumin (TBPA):
- Binds approximately 10% of circulating T4 and lesser amounts of T3
- Albumin:
– Binds approximately 15% of circulating T4 and T3
Draw and label diagrams associated with thyroid-binding protein function.
Refer to slide 21 + 22.
Where are thyroid hormones secreted?
Explain the effect of thyroid hormones when released.
Which type of drugs can suppress TSH secretion?
Explain the general relationship between TSH release, dopamine, somatostatin and glucocorticoids.
What type of thyroid-binding protein are most of the thyroid hormone (T3 & T4) bound to?
Explain the mechanism of action of T3 and T4 hormones.
Explain the major functions of thyroid hormones.
Draw and label the diagram for thyroid hormone secretion regulation.
What are the effects of hypothyroidism?
What are the effects of hyperthyroidism?
Give examples of thyroid disorders associated with hyperthyroidism.
What is Graves’ Disease?
What are the main characteristics of Graves’ Disease?
Draw and label the diagram that represents the effects of Graves’ Disease.
What are the manifestations of Thyroid Storm?
