Pathology of Thyroid Flashcards Preview

Endocrinology > Pathology of Thyroid > Flashcards

Flashcards in Pathology of Thyroid Deck (38):
1

What is the thyroid composed of, and what is each of these surrounded by?

Composed of follicles. Each follicle surrounded by flat to cuboidal follicular epithelial cells.

2

What is found within the centre of each follicle?

dense amorphic pink material containing thyroglobulin

3

What are C cells? What do they secrete?

(parafollicular cells). Slightly larger cells with clearer cytoplasm. Secrete calcitonin

4

What does TSH bind to?

TSH receptor on surface of thyroid epithelial cells.

5

What does cAMP do?

cAMP increases production and release of T3 and T4

6

Do T3 and 4 circulate in bound or free forms?

both

7

What occurs as a result of excess T3 and T4?

hyperthyroidism

8

What are 85% of hyperthyroidisms due to?

Grave's Disease

9

Is hashimotos thyroiditis related to hypo or hyperfunction of the thyroid?

hypo

10

What type of condition are Hashimoto’s
Thyroiditis and Grave's disease?

autoimmune

11

Descriebe the triad of features in Grave's disease.

Hyperthyroidism with diffuse enlargement of the thyroid
Eye changes (exophthalmos)
Pretibial myxoedema.

12

Why do eye changes occur in Grave's Disease?

The eye changes result from fibroblasts etc expressing TSH receptors

13

Who does Hashimotos commonly affect?

Affects middle aged women

14

Which genes is Hashimoto's associated with?

Associated with HLA – DR3 and DR5

15

Can iodine deficiency cause hyper or hypothyroidism?

hypo

16

Is hypothyroidism often a result of secondary (pituitary) or tertiary (hypothalamic) pathology?

no, rarely

17

What may mediate destruction of thyroid epithelium?

CD8 +ve cells

18

What may hashimoto's be preceded by?

by transient hyperfunction (Hashitoxicosis)

19

What causes a goitre?


Reduced T3 / T4 production causes rise in TSH, stimulating gland enlargement

20

If a goitre is present, can you maintain euthyroid state?

Yes (If compensation fails have goitrous hypothyroidism
)

21

What are the most common type of thyroid carcinomas?

papillary (75%)

22

What are adenomas encapsulated by?

a surrounding collagen cuff

23

What are thyroid adenomas composed of?

neoplastic thyroid follicles i.e. Follicular Adenoma

24

Are adenomas usually functional or non functional?

non-functional

25

Can adenomas secrete thyroid hormones?

yes (thyrotoxicosis)

26

When do thyroid carcinomas usually occur?

early adulthood

27

What type of carcinoma is ionising radiation related to?

papillary carcinoma

28

What type of carcinoma is iodine deficiency related to?

follicular

29

Which type of carcinoma has Associated Amyloid deposition?

medullary

30

What are medullary carcinomas composed of?

spindle or polygonal cells arranged in nests, trabeculae or follicles

31

Which type of thyroid carcinoma involves rapid growth and involvement of neck structures and death?

anaplastic

32

Which type of carcinoma, papillary of follicular, is more difficult to identify in thyroid cytology?

follicular

33

There are 4 parathyroid glands, but how many people only have 2 or 3?

10%

34

What are parathyroid glands composed of and supported by?

chief cells, supported by oxyphil cells

35

Does parathyroid hyperplasia involve all glands?

Yes

36

Does parathyroid adenoma involve all glands?

No, normally 1

37

What sort of mental state can be caused by hypoparathyroidism?

Emotional lability, anxiety, depression, confusion, psychosis

38

What can cause Dental abnormalities if hypocalcaemia during development?

hypoparathyroidism