Thyroid (pathology)

Question 1

where does the thyroid originate?

Answer 1

branchial arches 1&2 arches, then descends through foramen cecum w/thyroglossal duct

Question 2

thyroglossal duct makeup

Answer 2

endodermal, capsule and septa are hyprobranchial mesenchyme

Question 3

what happens if thyroid descends too far?

Answer 3

retrosternal thyroid

Question 4

where to C cells come from?

Answer 4

ultimobranchial bodies from 5th pouch

Question 5

problem with linqual thyroid

Answer 5

swollowing/obstruction

Question 6

most common location of functoning ectopic thyroid?

is there a cervical thyroid?

Answer 6

lingual

70% associated w/absence of cervical thyroid

Question 7

Thyroglossal Duct Cyst

Answer 7

Usually midline, between isthmus of thyroid and hyoid bone
Usually apparent at birth or in childhood
Tend to repeated infection
Not hormonally active

Question 8

Substernal Goiter

Answer 8

May be symptomatic (dyspnea, dysphagia, hyperthyroid, hypothyroid) or not

Question 9

“lateral aberrant thyroid” is most likely?

Answer 9

metastatic follicular thyroid carcinoma

Question 10

Struma Ovarii: a product of misplaced ovarian tissue during organogenesis?

Answer 10

NO

Question 11

Struma Ovarii

Answer 11

Monodermal teratoma of ovary, composed mainly (>50%) of adult thyroid tissue
May functionally cause thyrotoxicosis
Adenomas are common; 5% are malignant

Question 12

Exopthalmos
Non-pitting edema (pretibial myxedema)
Fatigue, weight loss, increased appetite
Tachycardia
Muscular weakness

Answer 12

Grave’s disease

Question 13

pathophys of Grave’s

Answer 13

Immune mediated production of TSH receptor antibodies:

Binding of antibodies to thyroid TSH receptors causes thyroid stimulation without negative feedback

Binding of the same antibodies to other tissue sites causes increased production of glycosamingclycans with resultant tissue effects (exopthalmos, myxedema)

Question 14

histologic features of Grave’s disease

Answer 14

scalloped colloid, hyperplastic epithelium

Question 15

Commonest cause of hypothyroidism in North America, where dietary iodine is sufficient

Answer 15

Hashimoto thyroiditis

Question 16

Hashimoto thyroiditis etiology

F:M?

Answer 16

autoimmune etiology, T cell defect

F:M 10:1 or 20:1

Question 17

Hyperthyroidism longevity & tx necessary?

Hypothyroidism longevity & tx necessary?

Answer 17

hyperthyroidism longevity
hyperthyroidism tx

hypothyroidism longevity
hypothyroidism tx

Question 18

Hashimoto is characterized by (hyper/hypo)thyroidism while late disease is characterized by (hyper/hypo)thyroidism?

Answer 18

Hashimoto is characterized by HYPERthyroidism while late disease is characterized by HYPOthyroidism

Question 19

granulomatous subacute thyroiditis

Answer 19

DeQuervain thyroiditis

Question 20

DeQuervain thyroiditis
M:F
peak season
probable etiology
histology

Answer 20

F:M is 3:1 to 5:1
season peak in summer
Probably a postviral inflammatory process
Not autoimmune, therefore self limited
giant cell formation

Question 21

unusual disorder of unknown cause characterized by fybrosis of thyroid and other neck structures as well as possibly retroperitoneum

Answer 21

Riedel Thyroiditis

adherent & difficult to remove. Difficult to dx histologically

Question 22

define goiter

Answer 22

A chronic enlargement of the thyroid gland, not due to a neoplasm, occurring endemically in certain locations, especially regions where glaciation occurred and the soil is low in iodine, and sporadically elsewhere.