Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pathology (Guide) > Chemical Pathology - Thyroid > Flashcards

Chemical Pathology - Thyroid Flashcards

1
Q

What are some causes of a raised TSH and low T4?

A

Hypothyroidism
- Atrophic
- Hashimoto’s
- Subacute (De Quervain’s)
- Postpartum
- Riedel thyroiditis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are some causes of a raised TSH and normal T4?

A
  • Treated hypothyroidism
  • Subclinical hypothyroidism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are some causes of a raised TSH and raised T4?

A
  • TSH secreting tumour
  • Thyroid hormone resistance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are some causes of a low TSH and raised T4 or T3?

A

Hyperthyroidism
- Grave’s disease
- Toxic multinodular goitre (Plummer’s)
- Toxic adenoma
- Drugs (thyroxine, amiodarone)
- Ectopic (Trophoblastic tumour, struma ovarii)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the cause of a low TSH and normal T3 or T4?

A

Subclinical hyperthyroidism
- Might progress to primary hypothyroidism (particularly if pt is anti-TPO antibody +ve)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are some causes of a low TSH and low T4?

A

Secondary hypothyroidism
- Hypothalamic/pituitary disorder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the cause of a raised then low TSH, and low T3 + T4 and why?

A

Sick euthyroid (with any severe illness)
- Body tries to shit down metabolism as thyroid gland has reduced output

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are some causes to a normal TSH and abnormal T4?

A
  • Assay interference
  • Changes in TBG
  • Amiodarone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the treatment of hypothyroidism?

A

Thyroid replacement therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the medical treatment for hyperthyroidism?

A
  • Sx relief: β blockers, topical steroids (dermopathy), eye drops for Sx eye disease with Graves
  • Antithyroid medications (Carbimazole)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the two approaches to giving antithyroid medication in hyperthyroidism and some side effects?

A
  1. Titration to normal T3
  2. Block + replace (cause hypothyroidism then give levothyroxine) - uncommon at high risk of SEs

SEs:
- Agranulocytosis
- Rashes (common)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

When is radio-iodine used in the treatment of hyperthyroidism and what is its main risk?

A
  • After medical therapy has failed
  • CI: Pregnancy + lactating women

Risk:
- Permanent hypothyroidism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the seven indications for a surgical hemi/total thyroidectomy in a patient with hyperthyroidism?

A
  • Women intending to become pregnant in next 6/12
  • Local compression secondary to thyroid goitre
  • Cosmetic
  • Suspected cancer
  • Co-existing hyperparathyroidism
  • Refractory to medical therapy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a thyroid storm and how is it treated?

A
  • Acute state that presents as shock with pyrexia, confusion + vomiting

Tx:
- HDU/ITU support
- Cooling
- High-dose anti-thyroid medications
- Corticosteroids
- Circulatory + respiratory support

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which enzyme is used to convert T4 to T3?

A

Deiodinase enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the roles of T3?

A
  • Acts as intramuscular receptor
  • Regulates basal metabolite rate
  • Potentiates response to catecholamines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How is thyroxine produced?

A
  • Thyroglobulin is produced in the follicular glands
  • Thyroglobulin is moved into the colloird where it is oxidised, iodinated + molecules are couples (T4)
  • T4 moved back to the follicular cell and then secreted in the blood stream
18
Q

What enzyme is used in the oxidation process of thyroglobulin?

A

Thyroperoxidase enzyme

19
Q

What are three causes of high uptake hyperthyroidism?

A
  • Graves Disease
  • Toxic multinodular goitre
  • Toxic adenoma
20
Q

What are three causes of low uptake hyperthyroidism?

A
  • Subacute De Quervains Thyroiditis
  • Portpartum thyroiditis (Like De Quervain’s but post-partum)
  • Ectopic
21
Q

What are two causes of autoimmune hypothyroidism?

A
  • Primary Atrophic HypoT (Commonest cause in UK)
  • Hashimoto’s Thyroiditis
22
Q

What are other causes of hypothyroidism?

A
  • Iodine deficiency (Most common worldwide)
  • Post-thyroidectomy/radioiodine
  • Drug induced
  • Riedel’s thyroiditis
23
Q

What are some features of Graves Disease?

A
  • 40-60% of all hyperthyroidisms
  • F > M (9:1)

Sx:
- Painless goitre

  • Anti-TSH receptor Abs
  • High diffuse uptake (isotope scan)
24
Q

What are some features of a toxic multinodular goitre (Plummer’s)?

A
  • 30-50% of all hyperthyroidisms

Sx:
- Painless

  • High uptake hot nodules (isotope scan)
  • Enlarged follicular cells distended with colloid + flattened epithelium
25
Q

What are some features of a toxic adenoma?

A
  • 5% of all hyperthyroidisms
  • Hot nodule (isotope scan) - one area of uptake
  • Solitary
26
Q

What are some features of Subacute De Quervains Thyroiditis?

A
  • Post-viral inflammation of the thyroid gland
  • Self-limiting

Sx:
- Painful Goitre

  • Initially hyperthyroid then hypothyroid
27
Q

What are some ectopic causes of hyperthyroidism?

A
  • Trophoblastic tumour
  • Struma ovarii (excessive hCG)
28
Q

What are some features of primary atrophic hypoT?

A
  • Diffuse lymphocytic infiltration causing atrophy

Sx:
- No goitre
- Small thyroid

  • No known antibodies

A/w:
- pernicious anaemia
- Vitiligo
- Endocrinopathies

29
Q

What are some features of Hashimoto’s thyroiditis?

A
  • Plasma cell infiltration
  • Elderly females
  • Autoimmune

Sx:
- Goitre
- Painless

  • ?Initial Hashitoxicosis
  • Anti-TPO + Anti-TTG
  • HURTHLE CELLS
30
Q

What drugs can induce hypothyroidism?

A
  • Antithyroid drugs
  • Lithium
  • Amiodarone
31
Q

What are some features of Riedel’s Thyroiditis?

A
  • Dense fibrosis replacing normal parenchyma
  • Painless

STONY HARD

32
Q

What demographic are thyroid tumours most commonly seen in?

A
  • Caucasian
  • Middle-aged
  • Women
33
Q

What indicates a high risk of neoplasm in thyroid tumours?

A
  • Solitary
  • Solid
  • Young
  • Male
  • Cold nodules
34
Q

What are the five types of thyroid tumours, their prevalence, prognosis + epidemiology?

A

Papillary:
- 75-85%
- 20-40yrs, Female
- A/w irradiation
- V. good prognosis

Follicular:
- 10-20%
- 40-60yrs
- Good prognosis

Medullary:
- 5%
- 50-60yrs
- 80% sporadic, 20% famililal MEN2

Anaplastic:
- Rare
- Elderly
- Poor prognosis (most die <1yr)

Lymphoma:
- Diffuse large B-cell lymphoma
- Good prognosis

35
Q

What are some features of Papillary Thyroid Tumours, it’s tumour marker, spread, histology + management?

A
  • Painless cervial lymphadenopathy
  • No clinical abnormalities of thyroid
  • Non-encapsulated

Tumour Marker = THYROGLOBULIN

Spread = LNs + Lung

Histology:
- PSAMMOMA BODIES (foci of calcification)
- Empty-appearing nuclei with central clearning (ORPHAN ANNIE EYES)

Mx:
- Surgery +/- Radioiodine
- Thyroxine

36
Q

What are some features of Follicular Thyroid Tumours, it’s tumour marker, spread, histology + management?

A
  • Well-differentiated, encapsulated

Tumour Marker = THYROGLOBULIN

Spread = BLOOD (spreads early) then to lungs, bone, liver, breast, adrenals

Histology:
- Fairly uniform cells forming small follicles
- Reminiscent of normal thyroid

37
Q

What are some features of Medullary Thyroid Tumours, it’s tumour markers, histology + management?

A
  • Neuroendocrine neoplasm derived from PARAFOLLICULAR C CELLS secreting CALCITONIN

Tumour marker = CEA + Calcitonin

Histology:
- Sheets of dark cells, amyloid deposition within tumour (calcitonin broken down to amyloid)

Mx:
- Screen for phaeochromocytoma pre-op
- Surgery
- Node clearance

38
Q

What are some features of Anaplastic Thyroid Tumours, its spread and histology?

A
  • Early + wide metastases common
  • Undifferentiated

Spread = Very aggressive (local, LNs, blood)

Histology:
- Undifferentiated follicular, large pleomorphic giant cells
- SPINDLE CELLS with sarcomatous appearance

Usually non-operable due to rapid growth

39
Q

What are some features of Diffuse Large B-cell lymphoma causing a thyroid tumour, its tumour marker and RFs?

A

MALToma

Tumour Marker = CD20

RFs:
- Chronic Hashimoto’s (lymphocyte proliferation)

40
Q

What is the basic management for a thyrotoxicosis crisis?

A
  • Β blocker
  • Steroid
  • Thioamide
41
Q

What are the three different types of Multiple Endocrine Neoplasia and their differences?

A

MEN1 (3Ps):
- Pituitary
- Pancreatic (e.g. insulinoma)
- Parathyroid (hyperparathyroidism)

MEN 2a (2Ps, 1M):
- Parathyroid
- Phaeochromocytoma
- Medullary Thyroid

Men 2b (1P, 2Ms):
- Phaeochromocytoma
- Medullary thyroid
- Mucocutaneous neuromas (+Marfanoid)

Pathology (Guide) (84 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions