Endocrinology

Question 1

What is an endocrine sign we might see as dentists?

Answer 1

Enlarged thyroid gland

Question 2

What are some endocrine causes of an abnormally large tongue?

Answer 2

Hypothyroidism, amyloidosis, lymphoma

Question 3

Which hormones are produced in the adrenal medulla?

Answer 3

Adrenaline and noradrenaline

Question 4

Which hormones are produced in the adrenal cortex?

Answer 4

Mineralocorticoids, glucocorticoids, androgens

Question 5

What is primary adrenal insufficiency?

Answer 5

Addison’s disease

Problem with adrenal gland itself, High ACTH

Question 6

What is secondary adrenal insufficiency?

Answer 6

Decreased pituitary ACTH production

Due to problem eg tumour in the pituitary gland

Question 7

What is tertiary adrenal insufficiency?

Answer 7

Glucocorticoid withdrawal (tablets, creams, inhalers, injections)

Question 8

What happens to ACTH levels in someone with adrenal insufficiency due to adrenal cause?

Answer 8

High ACTH

Question 9

What causes unusual pigmentation in Addison’s disease?

Answer 9

High levels of ACTH - ACTH is structurally similar to melanocyte stimulating hormone and so can act on melanocytes causing pigmentation

Question 10

Which type of adrenal insufficiency may be associated with abnormal pigmentation?

Answer 10

Primary / Addison’s disease

Question 11

What test can be used to diagnose adrenal insufficiency?

Answer 11

Short synacthen test

Question 12

What is the short synacthen test?

Answer 12

Tests for adrenal insufficiency by giving a synthetic injection of ACTH. A normal response would be to increase cortisol production

Note that this test stimulates the adrenal glands directly and not the hypothalamus pituitary axis

Question 13

What does the pituitary foundation recommend for tooth extractions?

Answer 13

20mg hydrocortisone or double the usual amount of prednisolone prior to tooth extractions

Question 14

What does the Addison’s disease self-help group suggest for dental procedures?

Answer 14

Check up or cleaning - no extra hydrocortisone

Planned LA - double or triple hydrocortisone dose 24h before; Unplanned LA - double or triple dose asap and continue for 24h

Question 15

How should a person with adrenal insufficiency manage their condition if they feel unwell?

Answer 15

Double up steroid dose

Take 100mg IM hydrocortisone if can’t take the tablets or are vomiting

Question 16

What is Cushing’s syndrome?

Answer 16

Excess cortisol

Question 17

Manifestations of Cushing’s syndrome?

Answer 17

Easy bruising, round moon face, red/purple striae, muscle weakness in arms and legs, osteoporosis, obesity, emotional disturbance

Question 18

What is facial plethora?

Answer 18

Swelling, puffiness and redness of the face

Can be a sign of Cushing’s disease

Question 19

Causes of Cushing’s Syndrome?

Answer 19

Steroid therapy, ACTH dependent eg ectopic ACTH secretion, ACTH independent eg adrenal adenoma or adrenal carcinoma

Question 20

What conditions are associated with hypercortisolism in the absence of Cushing’s syndrome?

Answer 20

Pregnancy, depression and other psychiatric conditions, alcohol dependence, morbid obesity

Question 21

What are the two biologically active thyroid hormones?

Answer 21

Thyroxine (T4) and triiodothyronine (T3)

Question 22

What is a key ingredient for the synthesis of thyroid hormones?

Answer 22

Iodine

Question 23

How is T4 converted to T3?

Answer 23

Deiodinases

Question 24

What are normal TSH levels?

Answer 24

0.35 to 4.5

Question 25

What are normal free T3 levels?

Answer 25

3-7

Question 26

What are normal T4 levels?

Answer 26

10-25

Question 27

What is levothyroxine?

Answer 27

Synthetic T4

Question 28

What can be used to treat primary hypothyroidism?

Answer 28

Levothyroxine

Question 29

Which gender is most affected by hypothyroidism?

Answer 29

Female

Question 30

Main causes of hypothyroidism?

Answer 30

Atrophic autoimmune thyroiditis, Hashimoto's thyroiditis, post treatment for thyrotoxicosis

Question 31

What is Graves' disease?

Answer 31

Overactive thyroid - increased levels of T3 and T4 ## Footnote Associated with antibodies

Question 32

What are the two most common causes of overactive thyroid?

Answer 32

Graves' disease, toxic multi-nodular goitre

Question 33

Signs of Graves' disease?

Answer 33

Smoothly enlarged goitre, protrusion of the eyes

Question 34

Treatment for thyrotoxicosis?

Answer 34

Tablets - carbimazole, PTU; radioactive iodine; surgery

Question 35

Risk of thyroid surgery?

Answer 35

Recurrent laryngeal nerve injury -> damage to voice, damage to parathyroid glands (low calcium levels)

Question 36

Differential diagnosis of a thyroid swelling?

Answer 36

Multinodular goitre with a dominant nodule, thyroid cyst, thyroid cancer

Question 37

What is acromegaly?

Answer 37

Excess growth hormone after long bone closure

Question 38

Signs of acromegaly?

Answer 38

Spaced teeth, enlarged facial features, thicker bones

Question 39

What is gigantism?

Answer 39

Hypersecretion of GH in children (before closure of long bones)

Question 40

What are some complications of acromegaly?

Answer 40

Visual field defects, headaches, diabetes, decreased libido, sleep apnoea, hypertension, cardiomyopathy, arthritis, carpal tunnel syndrome

Question 41

What would be increased in acromegaly?

Answer 41

IGF1

Question 42

What is the oral glucose tolerance test?

Answer 42

Test for diabetes that can also be used for acromegaly

Question 43

For diagnosing acromegaly, how often should blood be taken during the oral glucose tolerance test?

Answer 43

0 mins, every 30 mins up to 150 mins ## Footnote GH fails to suppress

Question 44

Treatment options for acromegaly?

Answer 44

Surgery to remove tumour, somatostatins, GH inhibition