Thyroid disease: Hyper, Hypo and other Flashcards
1
Q
Define Hypothyroidism
A
Underproduction of thyroid hormone
2
Q
Primary Hypothyroidism is due to what type of problem?
A
thyroid problem
3
Q
Secondary Hypothyroidism is due to what type of problem?
A
hypothalamic/pituitary problem
4
Q
Define Hyperthyroidism
A
overproduction of thyroid hormone
5
Q
What is thyrotoxicosis ?
A
Thyrotoxicosis refers to the symptoms caused by the excessive circulation of thyroid hormones.
6
Q
Define Euthyroid
A
normal production of thyroid hormone
7
Q
Define Goitre
A
enlargement of thyroid gland
8
Q
patients with a goitre may be: (3 things)
A
hyperthyroid, hypothyroid, euthyroid (normal thyroid function)
9
Q
Examination of the thyroid
A
low down in neck feel for thyroid cartilage (‘Adam’s apple) then down and laterally moves on swallowing diffuse or nodular? listen for a bruit retrosternal extension (can you get below it? percuss over sternum) check cervical LNS
10
Q
What does this image show?
A
X-ray of Retrosternal goitre causing tracheal deviation
11
Q
Interpreting thyroid function tests
remember …
A
the thyroid axis and negative feedback regulation
what is not working properly?
what is driving the system?
12
Q
Thyroid function tests are extremely common, … in every … have there thyroid function checked annually
A
1 in every 4
13
Q
Normal thyroid function test ranges (info)
TSH?
FT4?
FT3?
What Thyroid antibodies are tested?
A
0.3 - 4.2 mu/l
12-22 pmol/l
3.1-6.8 pmol/l
Anti-TPO AB - thyroid peroxidase auto-antibody
TRAB - TSH receptor autoantibody
14
Q
What are the two thyroid antibodies?
A
Anti-TPO AB - thyroid peroxidase auto-antibody
TRAB - TSH receptor autoantibody
15
Q
Thyroid stimulating hormone is the best …
A
biomarker of thyroid status
16
Q
Shape of TSH curve
- there is a tail from … upwards
- in this population, more patients have what?
A
tail from 3 upwards
increased frequency of thyroid antibodies
17
Q
TSH is quite … to respond to change - takes about … weeks
A
slow - takes about 6 weeks
18
Q
TSH assumes a normal … function
A
pituitary
must measure free thyroid hormones in patients with pituitary problem
19
Q
Thyroid autoantibodies
The prevalence of autoantibodies is … than the prevalence of autoimmune disease
- some are causal in disease, whereas some are viewed as a marker of …
- many auto antigens are sequestered / …
- negative autoAB result does not exclude …
A
higher
risk marker
intracellular
the disease - presence just helps confirm diagnosis
20
Q
Different types of thyroid autoantibodies
- “…” - target thyroid for autoimmune …
- “…” - stimulate TSH receptor (TRAB)
A
- destructive
- stimulatory
21
Q
What are the symptoms below a sign of?
- may be none
- lethargy
- mild weight gain
- cold intolerance
- constipation
- facial puffiness
- dry skin
- hair loss
- hoarseness
- heavy menstrual periods
A
hypothyroidism
22
Q
Severe hypothyroidism signs include:
A
- Change in appearance e.g face is puffy and pale
- periorbital oedema
- dry flaking skin
- diffuse hair loss
- bradycardia
- signs of median nerve compression - carpal tunnel
- effusions, e.g. ascites, pericardial
- delayed relaxation of reflexes
- croaky voice
- goitre
- rarely stupor or coma
23
Q
The symptoms below are a sign of what?
- Change in appearance e.g face is puffy and pale
- periorbital oedema
- dry flaking skin
- diffuse hair loss
- bradycardia
- signs of median nerve compression - carpal tunnel
- effusions, e.g. ascites, pericardial
- delayed relaxation of reflexes
- croaky voice
- goitre
- rarely stupor or coma
A
severe hypothyroidism
24
Q
Causes of Primary Hypothyroidism include: (6 things)
High TSH, low T4, low T3
A
- autoimmune hypothyroidism
- hypothyroidism after treatment for hyperthyroidism (iatrogenic)
- thyroiditis
- drugs (e.g. lithium, amiodarone)
- congenital hypothyroidism
- iodine deficiency (NOT UK)
25
Causes of Secondary Hypothyrodism is ...
* Caused by diseases of the ... or ...
* Low TSH, low T4, low T3
* rare
* Diseases of they hypothalamus or pituitary
26
_Investigations - Primary hypothyroidism_
* Bloods - TSH (normal range 0.3-4) and FT4 (normal range 10-24) ,what results would be expected?
* Do these confirm the diagnosis?
* What else could we check?
* Is imaging necessary?
Higher TSH (E.g. 22miu/l) and Lower FT4 (e.g. 8pmol/l)
* yes - diagnosis confirmed with blood results
* could also check thyroid autoantibodies
* no imaging is necessary
27
_Treatment for hypothyroidism_
* start with ..., ... micrograms daily (Depending on size/weight of patient)
* if patient has ischaemic heart disease or is over 65 - start with less (...-... micrograms daily) with increments 4-6 weekly
* USUAL DOSE = ?
* the aim is to achieve a normal ... level without ... suppression
* no evidence in properly conducted trials to support combination therapy of ... and ...
* start with **thyroxine**, **100micrograms**
* use less in these patients - **25-50** micrograms to begin with
* usual dose is **100-150** micrograms
* aim - normal **FT4** without **TSH** suppression
* no evidence for combo of **T3 and T4**
28
_Chronic autoimmune thyroiditis_
* also known as ... disease
* this term is used to imply that the patient has a ... or that their thyroid shows signs of ... infiltration
* hashimoto's disease
* this term is used to imply that the patient has a goitre or that their thyroid shows signs of thyroid infiltration
29
Myxoedema (coma)
* the accumulation of ... in interstitial spaces of tissues
* it is a very ... type of ...thyroidism
* glycosaminoglycans
* very severe hypothyroidism
30
_What are the symptoms below a sign of?_
* weight loss
* lack of energy
* heat intolerance
* anxiety/irritability
* increased sweating
* increased appetite
* thirst
* palpitations
* pruritus
* weight gain
* loose bowels
* oligomenorrhoea
thyrotoxicosis / hyperthyroidism
31
Symptoms of thyrotoxicosis (hyperthryoidism) include:
* weight loss
* lack of energy
* heat intolerance
* anxiety/irritability
* increased sweating
* increased appetite
* thirst
* palpitations
* pruritus
* weight gain
* loose bowels
* oligomenorrhoea
32
_Signs associated with thyrotoxicosis:_ (8)
* tremor
* warm, moist skin
* tachycardia
* brisk reflexes
* eye signs
* thyroid bruit
* muscle weakness
* atrial fibrilation
33
_What are the signs below associated with?_
* tremor
* warm, moist skin
* tachycardia
* brisk reflexes
* eye signs
* thyroid bruit
* muscle weakness
* atrial fibrilation
thryotoxicosis/hyperthyroidism
34
_Thyroid eye disease (TED) / thyroid associated ophthalmopathy (TAO)_
* Associated with autoimmune ... (known as ... disease) in approx 20% of patients
* They may not occur at same time, or at all
* increased risk in ...
* ... mediated
* inflammation of all orbital tissues except the ...
* ... scan imaging helpful
* Associated with autoimmune **hyperthyroidism** (known as **grave's** disease) in approx 20% of patients
* They may not occur at same time, or at all
* increased risk in **smokers**
* **autoantibody** mediated
* inflammation of all orbital tissues except the **eye**
* **CT** scan imaging helpul
35
_Symptoms of thyroid eye disease (TED) / thyroid associated ophthalmopathy (TAO)_
**_Mild:_**
* eyes are ... / ...
* artificial ... may help
* '....' eyes / change in appearance
* eyes are **dry**/ **itchy**
* artificial **tears** may help
* '**prominent**' eyes / change in appearance
36
_Symptoms of thyroid eye disease (TED) / thyroid associated ophthalmopathy (TAO)_
**_Worrisome:_**
* loss of sight / ...
* loss of ... vision (patches are .../...)
* swelling of .../redness
* unable to ... eyes fully
* ache/pain/tightness ... or ... eye
* loss of sight /**diplopia**
* loss of **colour** vision (patches are **grey/blurred)**
* swelling of **conjunctiva**/redness
* unable to **close** eyes fully
* ache/pain/tightness **in** or **behind** eye
37
What is shown in this image? (eyes - thyroid eye disease)
* MRI T2 weighting STIR sequencing
* **shows inflammatory activity of extraocular muscles**
38
What disease is present?
thyroid eye disease
39
Signs associated with thyrotoxicosis:
* Hands (2 signs)
1. fine tremor
2. warm
40
_Signs associated with thyrotoxicosis:_
* Pulse (2 signs)
* sinus tachycardia
* atrial fibrillation
41
_Signs associated with thyrotoxicosis:_
Neck (4 signs)
* goitre
* move when swallow
* smooth/not
* bruit/not
42
_Signs associated with thyrotoxicosis:_
Eyes (4 signs)
* lid retraction/lag
* proptosis/exophthalmos
* ophthalmoplegia (abnormal eye movements, causes diplopia)
* inflammation (conjunctiva)
43
_What is diplopia?_
technical term for double vision.
44
What is Ophthalmoparesis?
refers to weakness (-paresis) or paralysis (-plegia) of one or more extraocular muscles which are responsible for eye movements.
45
What is proptosis/exophthalmos?
Exophthalmos, also known as proptosis, is the medical term for bulging or protruding eyeballs.
46
_Causes of thyrotoxicosis_
* most common cause is ... ... (also known as what disease?)
* what happens in this disease? (autoantibody....)
* named after doctor who discovered it
* accounts for ...% of hyperthyroidism, typically women of what age?
* Autoimmune hyperthyroidism (Grave's disease)
* autoantibody stimulates the TSH receptor, causing excess thyroid hormone production and thyroid growth (goitre)
* 75% of hyperthyroidism - typically women 30-50 yrs
47
_Other causes of thyrotoxicosis (4 things)_
1. toxic ... goitre
2. toxic ...
3. thyroiditis
4. drugs (such as...)
1. toxic multinodular goitre
2. toxic adenoma
3. thyroiditis
4. drugs (E.g. amiodarone)
Main cause is autoimmune hyperthyroidism
48
_Gestational thyrotoxicosis_
* HCG made by the ... has a very similar structure to ...
* more likely if hyperemesis (morning sickness) / twin pregnancy
* settles after ... trimester
* HCG made by the **placenta** has a very similar structure to **TSH**
* more likely if hyperemesis / twin pregnancy
* settles after **1st** trimester
49
_Helpful diagnostic features (Cause of hyperthyrodism)_
_more likely to be Grave's disease if:_
* ... or ... hx of any autoimmune thyroid/endocrine disease
* Goitre with a ...
* 20% of those with ... have grave's disease
* positive thyroid ... titre
* **Personal** or **family** history
* Goitre with a **bruit**
* **thyroid eye disease**
* positive thyroid **autoantibody titre**
50
_Thyroid function tests for hyperthyroidism (e.g. Grave's disease)_
* TSH \< 0.1 miu/l (hyperthyroidism) vs normal range? higher or lower in hyperthyroidism?
* FT4 30pmol/l (hyperthyroidism) vs normal range? higher or lower in hyperthyroidism?
* FT3 10pmol/l (hyperthyroidism) vs normal range? higher or lower in hyperthyroidism?
* TSH \< 0.1 miu/l (hyperthyroidism) what is normal range? - **0.3-4 (lower in hyperthyroidism)**
* FT4 30pmol/l (hyperthyroidism) what is normal range? - **10-24 (higher in hyperthyroidism)**
* FT3 10pmol/l (hyperthyroidism) what is normal range? - **3-7 (higher in hyperthyroidism)**
**remember the negative feedback loop**
TSH suppressed because thyroid overactivity is supressing TSH production
51
_Further investigations for hyperthyroidism (after thyroid function tests)_
* thyroid ...
* may not need any ...
* thyroid ... scan (isotope scan)
* functional scan - darker areas of ... activity
* thyroid **autoantibodies**
* may not need any **imaging**
* thyroid **uptake** scan (isotope scan)
* functional scan - darker areas of **increased** activity
52
_Grave's disease treatment options include: (4 things)_
1. ...
2. ...
3. ...
4. ... control - use ... blockers but not in people who are ...
_OR - no treatment - what are the risks?_
1. **medical**
2. **radioiodine**
3. **surgery**
4. **symptom** control (beta blockers - propranolol but not if asthmatic)
OR - no treatment - what are the risks?
* symptoms worsening
* AF -\> stroke
* osteoporosis -\> fractures
53
_Medical Therapy for Grave's disease_
* 2 drug examples, what are they?
* how long do you treat for?
* you can block replace or ...
* rare side effect is ...
* What is the long term cure rate?
* how many relapse?
* **carbimazole** or **propylthiouracil** (PTU)
* **18 months - 2 years**
* **titrate** or **block replace**
* **agranulocytosis** is a rare side effect
* **1/3** long term cure rate
* **2/3 relapse -** usually in first year, cannot predict in advance
*
54
_What is Agranulocytosis?_
A rare condition in which your bone marrow doesn't make enough of a certain type of white cell, most often neutrophils.
55
_Radioiodine therapy for Grave's disease_
* it is given ...
* radioiodine is concentrated in the ... and kills ... cells
* medical therapy first until thyroid status is ...
* approx 40% risk of permanent ... after treatment
* do not give if ... or breast feeding
* need to avoid prolonged close contact with others for ... - ... weeks after - tricky if young children
* not if severe ... ... disease
* future pregancies - women wait ... months, men ... months
* warn patients about ... security systems
* it is given **orally**
* radioiodine is concentrated in the **thyroid** and kills **thyroid** cells
* medical therapy first until thyroid status is **euthyroid**
* approx 40% risk of permanent **hypothyroidism** after treatment
* do not give if **pregnant** or breast feeding
* need to avoid prolonged close contact with others for **1** - **2** weeks after - tricky if young children
* not if severe **thyroid eye** disease
* future pregancies - women wait **6** months, men **4** months
* warn patients about **airport** security systems
56
_Surgery for Grave's disease_
* sub-total ... ("almost total")
* patients must be ... pre-op
* medical therapy first
* risks include:
1. ...
2. ... scar
3. vocal cord ... (recurrent laryngeal nerve damage)
4. hypothyroidism
5. hypoparathyroidism
* sub-total **thyroidectomy** ("almost total")
* patients must be **euthyroid** pre-op
* medical therapy first
* risks include:
1. **anaesthetic**
2. **neck** scar
3. vocal cord **palsy**
4. hypothyroidism
5. hypoparathyroidism
57
_Treatment for a toxic adenoma or toxic multinodular goitre_
* initial treatment - short term ... therapy - to control thyroid function tests
* subsequent curative treatment - ...
* initial treatment - short term **medical** therapy - to control thyroid function tests
* subsequent curative treatment - **radioiodine**
58
_Agreeing expectations - treating hyperthyroidism_
* reassurance that variety of symptoms all relate to condition e.g ...
* may take time to feel normal again - there will be a '...' phase of a few months
* treatments for thyroid do not help with ... disease
* risk of weight ...
* confirm family plans - why?
* swings in emotion, anxiety, panic, irritability
* lag phase
* eye disease - treatment doesnt help
* risk of weight gain
* starting a family - have to wait after radioiodine
59
Blood results - what condition did the person have before starting treatment?
What stays suppressed for a while? what is best to monitor?
Hyperthyroidism
TSH stays suppressed for some time - monitor FT4
60
_Thyroid Eye Disease - treatment options_
**Active disease options include**
* encourage ... cessation
* steroids , examples?
* other immunosuppressive/ ...-sparing agents
* ...therapy
* encourage **smoking** cessation
* steroids - **pulsed IV methylpred/ oral prednisolone**
* other immunosuppressive/ **steroid**-sparing agents
* **radiotherapy**
61
_Thyroid Eye Disease - treatment options_
'Burnt out' thyroid eye disease:
* may be left with ... causing impaired QOL and social avoidance
* treatment is ... - 2 options are
* may be left with **disfigurement** causing impaired QOL and social avoidance
* treatment is **surgical** - 2 options are
1. **orbital decompression**
2. **eyelid surgery**
62
A rare but dangerous complication of Grave's disease is called thyroid ... or thyrotoxic ...
thyroid storm or thyrotoxic crisis
63
Who gets thyrotoxic crisis (thyroid storm?)
is it common?
* usually **secondary** to grave's
* **unrecognised**
* **incompletely** **treated** e.g. start stop, erratic compliance, early on in course, surgery/radioiodine treatment without adequate prep
* very **rare**
64
What triggers thyrotoxic crisis (thyroid storm?) (3 things)
* **surgery** (GA)
* **childbirth**
* **acute severe illness** such as infection, trauma, diabetic ketoacidosis, stroke, PE
65
_Features of thyroid storm_
* It is a ...-... condition
* typical features of ... disease
* hyperpyrexia
* CNS - agitation, delirium
* CNS symptoms include (4 things)
* GI symptoms include (3 things)
* It is a **multi-system** condition
* typical features of **grave's** disease
* hyperpyrexia
* CNS - agitation, delirium
* CNS symptoms include (4 things)
1. **tachycardia \>140bpm**
2. **atrial dysrhythmias**
3. **ventricular dysfunction**
4. **heart failure**
* GI symptoms include (3 things)
1. **nausea and vomiting**
2. **diarrhoea**
3. **hepatocellular dysfunction**
66
What is hyperpyrexia?
A term for a very high fever
| (occurs in thyroid storm)
67
Thyroid storm has a ... mortality rate and involves ... level care
**High** mortality rate and involves **ITU**-level care
68
Does degree of elevation of thyroid hormone concentrations distinguish between uncomplicated thyrotoxicosos and thyroid storm?
NO - does not distinguish - harder to recognise
69
_Thyroiditis_
* To begin, transient mild ...
* always ...
* B-blockers if required
* isotope scan would be '...'
* anti-thyroid drugs - do they work?
* longer phase of what? (4-6months)
* what % are normal within a year?
* what treatment may be required for a while? (during this phase)
* transient mild **thyrotoxicosis**
* always **resolves (1-2months)**
* B-blockers if required
* isotope scan would be '**cold**'
* anti-thyroid drugs - do they work? - **no**
* longer **hypothyroid phase (4-6months)**
* 80% normal at 1 year
* may require thyroxine treatment for a while
70
Annual TFTs for thyroiditis patients:
* What % hypothyroid at 1 year?
* What % hypothyroid at 3 years?
* What % hypothyroid at 1 year? - **30%**
* What % hypothyroid at 3 years - **50%**
71
Thyroiditis, consider if:
* patient is .../ within one year ...-...
* increased risk in type 1 ..., FHx of thyroid ..., smoker
* patient has a very ... thyroid
* may be raised ... markers
* clinical thyroid status does not fit with lab results, why?
* no diagnositic features of ... disease
* current/recurrent treatment with ... medication
* patient is **pregnant/** within one year **post-partum**
* increased risk in type 1 **diabetes**, FHx of thyroid **di****sease**, smoker
* patient has a very **tender** thyroid
* may be raised **inflammatory** markers
* clinical thyroid status does not fit with lab results, why? - **rapidly changing thyroid function tests**
* no **diagnositic** features of **grave's** disease
* current/recurrent treatment with **immunomodulatory** medication
72
Thyroid function tests - what condition? (thyroid)
* **baby in Jan**
postpartum thyroiditis
initially, low TSH, high FT4 - thyrotoxic - mildy
then, hypothyroid phase - high TSH, low FT4
73
_Association of autoimmune thyroid disease with other diseases_
**other autoimmune endocrine diseases include: (5)**
1. ... . ...
2. ... ...
3. ... disease
4. ... ... ...
5. ... disease
**syndromes: (2)**
1. ... syndrome
2. ...'s syndrome
Medication for other diseases:
1. lithium - what does this do?
2. amiodarone
**Annual Thyroid function test screening recommended in all of these situations**
1. **Type 1 diabetes**
2. **Pernicious anaemia**
3. **Coeliac disease**
4. **Premature ovarian failure**
5. **Addison's disease**
1. **Turner** syndrome
2. **Down's** syndrome
1. lithium - **inhibits Thyroid hormone synthesis and secretion**
2. amiodarone
74
_Goitre and thyroid nodules in euthyroid patients_
**_Euthyroid Goitre:_**
* **is it common?**
* where is it common?
* may be ...
* usually nothing to worry about
**_Thyroid nodule:_**
* must exclude thyroid ... - 5% cancerous, rest benign
* ... scan characterists helpful
* fine-needle ... biopsy for cytology
**_Euthyroid Goitre:_**
* **is it common? - yes**
* where is it common - **i****n iodine-deficient areas**
* may be **multinodular**
* usually nothing to worry about
**_Thyroid nodule:_**
* must exclude thyroid **cancer** - 5%
* **ultrasound** scan characterists helpful
* fine-needle **aspiration** biopsy for cytology
