Endocrinology: Thyroid Disease Flashcards

1
Q

Which symptom would differentiate between a patient is suffering from thyrotoxicosis as opposed to malignancy? [1]

A

Increase in appetite

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

Thyrotoxicosis symptoms:

General? [3]
CVS? [3]
Abdominal? [3]
GU? [1]
CNS? [3]

A

General symptoms
* tired, anxious, sweating

CVS
* palpitations, atrial fibrillation, heat intolerance

Abdo
* weight loss, frequency, appetite

GU
* Oligomenorrhoea

CNS
* tremor, eye problems, nuscle weakness, emotional / agitated

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

Name and explain drugs may you suspect of a patient’s DH, who is displaying symptoms of thyrotoxicosis [3]

A

Amiodarone (treats afib): high levels of iodine
Lithium: can mimic iodine
ARVs

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

What are T3/4 and TSH levels likely to be with a ptx suffering from thyrotoxicosis? [2]

A

TSH: low
T3/4: High

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

When can you only make a diagnosis of thyrotoxicosis? [1]

A

Can only make diagnosis of thyrotoxicosis if TSH levels are undetectable

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

State the main causes of thyrotoxicosis [5]

A

Graves Disease

Toxic Multinodular Disease

Toxic adenoma

Ectopic thyroid tissue

Exogenous (Lithium excess)

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

What type of Ig are the anti TSH receptor antibodies? [1]

A

IgG

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

Which cause of a goitre causes a painful goitre? [1]

A

Subacute (De Quervains)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

State 4 diffuse causes of goitre [4]

State 3 nodular causes of goitre [4]

A

Diffuse:
- Graves
- Hashimotos
- Subacute

Nodular:
- TMG
- Adenoma
- Carcinoma

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

Which antibodies are present in Graves disease? [1]

A

Thyroid-stimulating hormone receptor antibodies (TSHR-Ab): these antibodies mimic the action of TSH causing excessive stimulation of the gland.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Asides from TSHR-Ab, which other antibodies would you potentially test for in a ptx presenting with thyrotoxicosis? [1]

A

Thyroid Stimulating Immunoglobulin (TSI)

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

Cardinal signs of Graves disease? [3]

A

Opthalmopathy
Pre-tibial myxoedema
Acropachy

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

Describe basic overview of toxic multinodular goitre [1]

A

Multiple autonomous nodules develop that are capable of producing and secreting thyroid hormones.

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

Describe the structure of the goitre seen in Grave’s disease [1]

A

Diffuse smooth goitre with a bruit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which cardiac sign / symptom is the consequence of advanced/long-term action of excess TH on the heart? [2]

A

AF
Increase in ANP

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

State 5 risk factors for Graves Disease

A

FEMALE - biggest risk factor (onset is common postpartum)

  • Genetic - association with HLA-B8, DR3 & DR2
  • E.coli and other gram-NEGATIVE organisms contain TSH-binding sites so may initiate pathogenesis via ‘molecular mimicry’
  • Smoking
  • Stress
  • High iodine intake
  • Autoimmune disease:
  • Vitiligo (pale white patches on skin)
  • Addison’s disease
  • Pernicious anaemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which autoimmune diseases are commonly associated with Graves disease? [5]

A
  • Vitiligo (pale white patches on skin)
  • Addison’s disease
  • Pernicious anaemia
  • Myasthenia gravis
  • Type 1 DM
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What specifically does Graves opthalmology occur from? [1]

Describe the features of Graves opthalmology [6]

A

Results in retro-orbital inflammation and swelling of the extrocular muscles

  • Eye discomfort, grittiness, increased tear production, photophobia, diplopia, reduced acuity
  • Exophthalmos - appearance of protruding eye and proptosis - eye protrudes beyond orbit
  • Conjunctival oedema
  • Corneal ulceration
  • afferent pupillary defect
  • Ophthalmoplegia - paralysis of eye muscles Eyes are examined via CT/MRI of orbit
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the main risk factor for Grave’s eye disease? [1]

A

Smoking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which sign of Graves ophthalmology indicates that optic nerve is compressed? [1]

A

afferent pupillary defect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do you manage Graves opthamology? [3]

A
  • Most individuals with mild disease however can be treated symptomatically: artificial tears, sunglasses, avoid dust, sleep inclined to reduce periorbital oedema.
  • High dose steroids
  • Consideration of radiotherapy / surgical decompression if medical management is unsuccessful.

(The hyperthyroidism should also be dealt with if not already)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe the management for hyperthyroidism [4]

A

Anti-thyroid drugs:
- PROPYLTHIOURACIL (PTU) stops the conversion of T4 to T3
- ORAL CARBIMAZOLE which blocks thyroid hormone biosynthesis and also has immunosuppressive effects (which will affect Graves’ disease process

Radioactive iodine:
- RADIOACTIVE I(131) is given: contraindicated in pregnancy and breast feeding

Surgery: subtotal thyroidectomy only in those who have been rendered euthyroid (normal functioning thyroid gland); total thyroidectomy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

AEs of carbimazole? [3]

A

AGRANULOCYTOSIS - results in a severely low white blood cell count (leukopenia) - most commonly neutropenia: can lead to sepsis

Rash

Arthralgia

Hepatitis

Vasculitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

State 3 AEs of thyroid surgery [3]

A
  • Tracheal compression from postoperative bleeding
  • Laryngeal nerve palsy resulting in hoarse voice
  • Transient hypocalcaemia - due to removal of parathyroid gland too
24
Q

Signs of hypothyroidism?

A

BRADYCARDIC:
* Bradycardia
* Reflexes relax slowly
* Ataxia (cerebellar)
* Dry, thin hair/skin
* Yawning/drowsy/coma
* Cold hands +/- temperature drop * Ascites
* Round puffy face
* Defeated demeanour
* Immobile +/- Ileus (temporary arrest of intestinal peristalsis)
* Congestive cardiac failure

25
Q

Describe 5 causes of hypothyroidism [5]

A

Iodine deficiency: (most common cause in developing world):
* GOITRE FORMATION due to TSH stimulation causing thyroid enlargement

Autoimmune/atrophic hypothyrodisim:
* antithyroid autoantibodies leading to lymphoid infiltration of the gland and eventual atrophy and fibrosis - since there is atrophy there is NO GOITRE

Hashimoto’s thyroiditis:
- GOITRE FORMATION due to lymphocytic and plasma cell infiltration but with regeneration.
- Thyroid peroxidase antibodies (TPO-Ab) are present in HIGH TITRES

Post-partum thyroiditis:
- usually a transient phenomenon observed following pregnancy. Thought to result from modifications to the immune system necessary in pregnancy and histologically is a lymphocytes thyroiditis (AUTOIMMUNE)

Iatrogenic (caused by treatment or examination):
- Thyroidectomy - for treatment of hyperthyroidism or goitre
- Radioactive iodine treatment or external neck irradiation for head and neck cancer;
- too much of carbimazole; lithium; amiodarone

26
Q

How do you investigate for hypothyroidism? [4]

A

Thyroid function tests:
- High TSH; low T3/T4 (primary)
- Low TSH; low T3/T4 (secondary)

Thyroid antibodies (e.g. anti-TPO-Ab in Hashimotos)

Cortisol to ensure patient has a normal ACTH/cortisol reserve.
- Sometimes profound hypothyroidism can infiltrate tissues such as the adrenal gland and disrupt cortisol reseves. If thyroxide is given in these conditions it may trigger Addinsonian Crisis

Anaemia:
- Usually normochromic and normocytic
- May be macrocytic (sometimes due to pernicious anaemia)
- Or microcytic (in women, due to menorrhagia or undiagnosed coeliac disease)

27
Q

What is the standard treatment length of carbimazole of propylthiouracil? [1]

A

Maintain for 12-18 months then withdraw

28
Q

What are TFT results for:

Primary Hypothyroidism [2]
Secondary Hypothyroidism [2]

A

Primary Hypothyroidism:
- TSH high; T3/4 low

Secondary Hypothyroidism:
- TSH low; T3/4 low (v rare)

29
Q

Treatment for hypothyroidism?

A

ORAL LEVOTHYROXINE (T4)
- Aim is normal TSH conc. which will be achieved by levothyroxine - but don’t give too much so as to completely suppress TSH as this carries risk of AF and osteoporosis

30
Q

Describe what a thyroid crisis is [1], how it occurs [1], and features? [3]

A

Rare, life threatening condition in which there is a rapid deterioration of thyrotoxicosis (RAPID T4 INCREASE)
Features include hyperpyrexia, tachycardia, extreme restlessness
and eventually delirium, coma and death

Usually precipitated by stress, infection, surgery or radioactive
iodine therapy in an unprepared patient

31
Q

Treatment for thyroid crisis / storm? [4]

A
  • ORAL CARBIMAZOLE
  • ORAL PROPRANOLOL
  • ORAL POTASSIUM IODIDE (to block acutely the release of thyroid hormone from gland)
  • IV HYDROCORTISONE (to inhibits peripheral conversion of T4 to T3)
32
Q

Label A

A

TSH: low
T3/T4: high

33
Q

Label B

A

TSH: high
T3/T4: high

34
Q

Label C

A

TSH: high
T3/T4: low

35
Q

Label D

A

TSH: low
T3/4: low

36
Q

Name a complication of longstanding untreated hypothyroidism? [1]

A

Myxoedema coma

37
Q

Describe the features of a myxoedema coma [5]

A
  • hypothermia
  • cardiac failure (bradycardia)
  • hypoventilation
  • hypoglycaemia
  • hyponatraemia
  • myxoedema (thickened, swelling of skin)
38
Q

How do you treat a patient presenting with myxoedema coma? [3]

A
  • IV/ORAL T3
  • IV fluid
  • IV corticosteroids (until the possibility of coexisting adrenal insufficiency has been excluded)
  • Glucose infusion
  • Gradual rewarming
39
Q

Explain the 5 main types of thyroid carcinoma [5]

A

Papillary (70%):
* Most common, well differentiated
* Young people, local spread and good prognosis
* Arise from thyroid epithelium
* Lymph node metastasis predominate
* Usually contain a mixture of papillary and colloidal filled follicles
* Histologically tumour has papillary projections and pale empty nuclei

Follicular (20%):
* Middle age, spread to lung/bone, usually good prognosis
* 3x more likely in women
* Well differentiated, arise from thyroid epithelium
- Follicular adenoma: Usually present as a solitary thyroid nodule. Malignancy can only be excluded on formal histological assessment.
- Follicular carcinoma: Capsular invasion seen microscopically, and without this finding the lesion would be a follicular adenoma. Vascular invasion predominates unlike papillary which is lymph-node predominant

Anaplastic (< 5%):
* Very undifferentiated and arise from thyroid epithelium
* Aggressive, local spread but poor prognosis

Lymphoma (2%)
* Can be associated with Hashimoto’s

Medullary cell (5%):
* C cells derived from neural crest and not thyroid tissue
* Serum calcitonin levels often raised
* Both lymphatic and haematogenous metastasis are recognised, nodal disease is associated with a very poor prognosis.

40
Q

Which is the most common type of thyroid carcinoma? [1]

A

Papillary (70%)

41
Q

Raised calcitonin levels would indicate which type of thyroid cancer? [1]

A

medullary thyroid cancer (arise from calcitonin C cells of thyroid gland)

42
Q

Which types of thyroid cancers are differentiated? [2]
Which types of thyroid cancers are undifferentiated? [1]

A

Differentiated:
- papillary
- follicular

Undifferentiated:
- anaplastic

43
Q

General treatment of thyroid carcinomas? [4]

A
  • Administer lots of LEVOTHYROXINE (T4) to keep TSH reduced as this is a growth factor for the cancer!
  • Iodine 131 ablation
  • Thyroidectomy
  • Chemotherapy helps to reduce risk of spread and treats micro-metastases that have been undetected
44
Q

What are the three stages of De Quervain’s thyroiditis? [3]

A

De Quervain’s thyroiditis, also known as subacute thyroiditis, is a condition causing temporary inflammation of the thyroid gland. There are three phases:

Thyrotoxicosis
Hypothyroidism
Return to normal

45
Q

De Quervain’s thyroiditis usually occurs after what? [1]

A

A viral infection

46
Q

Describe the initial thyrotoxic phase of De Quervain’s thryoiditis [3]

A
  • Excessive thyroid hormones
  • Thyroid swelling and tenderness
  • Flu-like illness (fever, aches and fatigue)
  • Raised inflammatory markers (CRP and ESR)
47
Q

Which thyroid carcinomas respond to iodine-131 ablation? [2]
Which do not? [2]

A

Ablative radioactive iodine:
- Papillary and follicular carcinomas

Anaplastic carcinomas and lymphomas:
- DO NOT respond to radioactive iodine

48
Q

TOM TIP: The MHRA issued a warning in 2019 about the risk of [] in patients taking carbimazole.

In your exams, look out for a patient on carbimazole presenting with symptoms of []

A

TOM TIP: The MHRA issued a warning in 2019 about the risk of acute pancreatitis in patients taking carbimazole.

In your exams, look out for a patient on carbimazole presenting with symptoms of pancreatitis (e.g., severe epigastric pain radiating to the back).

49
Q

TOM TIP: Both carbimazole and propylthiouracil can cause agranulocytosis, with a dangerously low white blood cell counts. Agranulocytosis makes patients vulnerable to severe infections.

[] is a key presenting feature of agranulocytosis. In your exams, if you see a patient with a sore throat on carbimazole or propylthiouracil, the cause is likely agranulocytosis. They need an urgent full blood count and aggressive treatment of any infections.

A

TOM TIP: Both carbimazole and propylthiouracil can cause agranulocytosis, with a dangerously low white blood cell counts. Agranulocytosis makes patients vulnerable to severe infections.

A sore throat is a key presenting feature of agranulocytosis. In your exams, if you see a patient with a sore throat on carbimazole or propylthiouracil, the cause is likely agranulocytosis. They need an urgent full blood count and aggressive treatment of any infections.

50
Q

How do you adapt a pregnant women’s dose of levoythroxine due to their pregnancy? [1]

A

In pregnancy, anyone already on levothyroxine treatment should increase their dose. Thyroid doses should be adjusted in steps of 25-50mcg. In pregnancy, the increase in thyroid replacement is typically 20-50%, which normally equates to 25mcg-50mcg increase.

51
Q

You suspect an underlying thyroid malignancy and send her for further imaging which confirms a malignancy, likely thyroid in origin. Her case is brought up at the next multi-disciplinary team meeting (MDT) and her prognosis is considered to be excellent.

What is the most likely diagnosis?

Anaplastic thyroid cancer

Follicular lymphoma

Follicular thyroid cancer

Medullary thyroid cancer

Papillary thyroid cancer

A

You suspect an underlying thyroid malignancy and send her for further imaging which confirms a malignancy, likely thyroid in origin. Her case is brought up at the next multi-disciplinary team meeting (MDT) and her prognosis is considered to be excellent.

What is the most likely diagnosis?

Anaplastic thyroid cancer

Follicular lymphoma

Follicular thyroid cancer

Medullary thyroid cancer

Papillary thyroid cancer

Papillary Prognosis is Perfect

52
Q

Which of the following often has lymph node metastasis?

Anaplastic thyroid cancer

Follicular lymphoma

Follicular thyroid cancer

Medullary thyroid cancer

Papillary thyroid cancer

A

Which of the following often has lymph node metastasis?

Anaplastic thyroid cancer

Follicular lymphoma

Follicular thyroid cancer

Medullary thyroid cancer

Papillary thyroid cancer

53
Q

Which of the following does not respond very well to treatment?

Anaplastic thyroid cancer

Follicular lymphoma

Follicular thyroid cancer

Medullary thyroid cancer

Papillary thyroid cancer

A

Which of the following does not respond very well to treatment?

Anaplastic thyroid cancer

Follicular lymphoma

Follicular thyroid cancer

Medullary thyroid cancer

Papillary thyroid cancer

Anaplastic is Awful (not treatment responsive usually)

54
Q

How do the following types of thyroid cancer spread?

  • Papillary [1]
  • Follicular [1]
A

PL - premier league = papillary + lymphatic spread

FH - follicular + haematogenous spread

55
Q

DDescribe the presentation of subacute thyroiditis in the first stage [3]

A

PAINFUL goitre
Raised ESR (caused by inflammation to thyroid)
Hyperthyroidism features

56
Q

Subacute thyroiditis occurs after an infection from which type of organism? [1]

A

Post-viral infection

57
Q

Describe the uptake of iodine in subacute thyroiditis [1]

A

No increase uptake: thyroid is inflammed due to infection.
Lots of T4 released, but it is acutely damaged and not producing any more during period