Thyroid Clinical Flashcards
1
Q
What causes hypothyroid
A
Usually primary but can be 2
Hashiomoto’s = most common
Iodine deficiency
Lithium
2
Q
What can cause hypo and hyperthyroid
A
Subacute thyroiditis
Post-partum thyroiditis - usually transient but presence of Ab makes it more likely to persist
Amiadarone
3
Q
What causes hyperthyroid
A
Grave’s
Toxic multi nodular goitre
4
Q
TSH and T4 levels primary hypothyroid
A
TSH =.high as trying to stimulate
T4 = low
5
Q
Secondary hypothyroid
A
TSH = low T4 = low
6
Q
Subclinical hypothyroid
A
TSH = High - to maintain hormone T4 = normal but will become love
7
Q
Poor compliance with thyroxine
A
TSH high
T4 normal
8
Q
Grave’s / hyperthyroid
A
TSH low
T4 high
9
Q
What are symptoms of hyperthyroid
A
Increased BMR + heat production - Weight loss - Heat intolerance Increased protein catabolism - Muscle weakness Increased CVS - Tachycardia - Palpitations - HF due to increased CO / angina - AF Hyper-reflexia Autonomic Sx Increased appetite Bone resorption / osteoporosis Anxiety Irritable Oligomenorrhoea Sexual dysfunction Goitre Thyroid eye disease
10
Q
What affect does Thyroid hormone have on CVS
A
Permissive to epinephrine
11
Q
What are autonomic Sx
A
Sweating
Tremor
Diarrhoea
12
Q
What are symptoms of hypothyroid
A
Decreased BMR + heat - Weight gain - Cold Disrupted protein - Thick skin - Dry skin - Dry coarse scalp hair - Hair loss - Brittle nails Dereased CVS - Brady - Oedema Fluid retention = oedema, ascites, effusion Slow reflexes Carpal tunne Depression Aching joints Lethargy Constipation Menorrhagia Giotre
13
Q
What does severe hypothyroid cause
A
Puffy face Large tongue Hoarse voice Coma Pleural effusion + oedema
14
Q
What causes thyroid eye disease
A
Hypo or hyper
15
Q
What are RF
A
Smoking
RAI
16
Q
What are features
A
What are signs from least to most severe
Proptosis / exompthalos = same but used for Grave’s
Extra-ocular - opthamoplegia = paralysis
Corneal involvement
Sight loss
- Optic disc swelling
17
Q
How do you Rx
A
Topical lubricant
Steroid
RT
Surgery
18
Q
When do you get urgent ophthalmology review
A
Unexplained deterioration in vision Change in colour vision Hx eye popping out (globe subluxation) Corneal opacity Cornea visible when eye closed Disc swelling
19
Q
What causes primary hypothyroid
A
Congenital Autoimmune -Hashiomoto's Iatrogenic Chronic iodine deficiency Post subacute thyroiditis 'De Quervain's Somatostatin Glucocorticoids
20
Q
What are iatrogenic causes
A
Post thyroidectomy for hyperthyroid RAI Anti-thyroid drugs External RT Lithium Amiadarone
21
Q
Congenital causes
A
Type 4
Maternal iodine deficiency
22
Q
What is Hashimoto’s
A
Autoimmune destruction of thyroid gland
Cytotoxic T cells/ cytokines
Causes diffuse enlargement of gland / goitre to compensate
Can initially be hyperthyroid
23
Q
What is associated with Hashimoto / Grave’s
A
DM
Addison’s
Pernicious anaemia
24
Q
What Ab
A
Ab to thyroglobulin and thyroid peroxidase (TPO)
25
What causes secondary hypothyroid due to pituitary damage
Tumour
Craniopharyngioma
Post surgical Sheehan's
Isolated TRH deficiency
26
What is subclinical hypothyroid
Mild symptoms but normal thyroid
| Raised TSH to maintain at normal level
27
When do you consider treatment (don't need to Rx )
If TSH >10
If TSH >5 with Ab present
Pregnancy
Symptomatic
28
What would overRx lead to
Osteoporosis
AF
as causes hyperthyroid
29
How do you investigate
TFT
Ab
Blood
30
What do you look for in blood of person with hypothyroid
```
Macrocytic anaemia
Hyponatraemia due to SIADH if tumour
Hyper-Cholesterol
Hyper-Prolactin
Increased muscle enzymes
```
31
How do you Rx
Levothyroxine (T4)
Titrate until stable
If TSH low then T4 dose too high
32
What do you do if change dose
Check levels after 8-12 weeks of TSH
33
What are SE and what drugs affect absorption
Hyperthyroid
Reduced BMD
Worsening angina
AF
Iron affect absorption / food so take 30 mins before
34
What are special situations
If IHD start at lower dose as may precipitate angina by increasing HR
If pregnant may need increased dose
35
What causes primary hyperthyroid
```
Grave's disease = most common
Toxic mulinodular goitre - 2nd most
Thyroid adenoma / solitary nodule
De-Quervains following viral infection
Drugs - amiadarone
```
36
What are causes of secondary hyperthyroid
Pituitary adenoma secreting TSH = rare
37
What causes thyrotoxicosis without hyperthyroid
Destruction as release hormones
- Amiadarone
- Post partum
Excessive levothyroxine
38
What is Grave;s disease
Ab produced that mimics TSH and activates thyroid
TSH receptor Ab = 90%
Anti-thyroid peroxidase
39
What causes the thyroid eye disease in Grave's
TSH receptor in ocular fibroblasts
40
How does it present
```
Signs of hyperthyroid
Diffuse goitre due to hyperplasia
Gynaecomastia
Clubbing
Nausea
Sweating
Eye disease - can cause corneal involvement / sight loss if optic nerve involved
May have mild neutropenia
```
41
What are signs of Grave's NOT hyperthyroid
```
Exophthalmos
Opthalmoplegia
Pretibial myxoedema - discoloured waxy deposit
Thyroid acropachy - clubbing, painful finger and toe swelling
Other autoimmune disease
- Myasthenia gravis
- Vitiligo
- Pernicious anaemia
```
42
How do you Rx Grave's
Anti-Thyroid drugs
RAI
Surgery to remove but will be left hypothyroid requiring levothyroxine
BB for symptoms by blocking adnrenaline (slow HR and improve tremor and anxiety)
43
What is most common regimen of anti-thyroid and what do you give after to destroy gland
Titration for 12-18 months
Can block replace - where block all then give thyroid
Carbimazole = 1st line
Propythiouracil
RAI
44
What does carbimazole do
Blocks thyroid peroxidase so reduces production of hormone
| Give in high dose till euthyroid then reduce
45
What are SE
Agranulocytosis
Rash
Neutropenia so if develop infectious symptoms = urgent medical review
46
What does propythiouracil do
Same
Also prevents conversion of T4-T3
RARE risk of liver reaction causing death
47
When would you give long term low dose anti-thyroid
Elderly
Cardiac
Unwilling for RAI
48
What are risks of RAI
Hypothyroid
No contact children / pregnancy for 4 weeks
No pregnancy 6 months
May worsen eye disease
49
What is important in Hx of thyroid issue
```
Symptoms of hyperthyroid
Any previous thyroid issue or surgery
Any cardiac Sx
FH autoimmune
DH
Any stress at home / depression
```
50
Who is most common to get multi-nodular goitre
Elderly
51
What are symptoms
Characteristic goitre due to hyperplasia
Doesn't listen to TSH and just releases hormones
Painless
Absence of Grave's - no Ab
52
How do you Dx
Nuclear scintigraphy
| Main concern = malignancy but tend to be euthyroid
53
How do you Rx
RAI or surgery if compression symptoms e.g. dysphagia or dyspnoea
54
What is subclinical hyperthyroid
TSH suppressed but normal hormone
55
What causes
Excessive thyroxine
| Multi-nodular goitre
56
What are concerns
Decreased bone density
AF
Dementia
57
When do you treat
If elderly or cardiac risk
58
What is subacute thyroiditis 'De Quervain's
Thyrotoxicosis for 3-6 weeks then hypothyroid
59
What causes
Younger patient
| Viral trigger - entero / coxsackie
60
What are symptoms of thyrotoxicosis
```
Raised ESR
Painful goitre
Fever
Myalgia
Dysphagia if compress
```
61
How do you Rx
Self-limiting
NSAID for pain
BB for hyper Sx
Steroids if hypo develops
62
What is a thyroid storm
```
Life threatening complications of untreated severe thyrotoxiosis
Fever >38.5
Tachycardia
HTN
Confusion
Agitation
N+V
Abdo pain
HF
AF
Arrhythmia - can push into CCF
Abnormal LFT + jaundice
Seizure
```
63
What precipitates
```
Infection
Surgery
Trauma
PE
DKA
PET
Acute iodine
```
64
How do you Rx
```
Admit to monitor
Paracetamol
Treat underlying event
IV BB
May need fluid
AA if AF
Anti-thyroid - propylthiouracil
IV hydrocortisone e to prevent conversion from T4-T3
```
65
How does hyper or hypo cause goitre and what should you think
```
Hyper = overactivity e.g. Grave's
Hypo = increased TSH due to hypo e.g. Hashimoto
```
Is it
- Diffuse enlargement
- Nodular
- What is patients thyroid status
66
What are physiological causes
Puberty
| Pregnancy
67
Wha are risk
Haemorrhage as highly vascular
68
What are types of goitre
```
Solitary thyroid nodule
Multinodular
Diffuse colloid
Diffuse simple
Cyst
Tumour
Sarcoid / TB
```
69
What can tumour be
Adenoma
Carcinoma
Lymhpoma
70
What does a solitary nodule in thyroid gland suggest if present along with
```
Malignancy if
Child
Adult <30 or >60
Painful
Previous head or neck RT
Cervical LN
```
More likely adenoma / cyst or discrete nodule in MNG
71
What should you always do for large dominant nodule in multi-nodule
Investigate as 5% malignant
72
How do you investigate
```
TFT - TSH
USS + FNA = 1st line if suspicious
T4 and thyroid ab if abnormal
Isotope scan
CXR
```
73
If hypo
Less likely malignant
74
What are differentiated thyroid cancers
Papillary
| Follicular
75
What is most common and what is it associated with
```
Papillary
<50
BRAF / RET gene
Exposure to radiation
Multifocal
```
76
Where does papillary spread and prognosis
Lymph so may present LN
| Good prognosis
77
How foes follicular present and what is association
Single lesion
Mets to lung / bone / blood
RAS mutation
78
How do you manage differentiated tumour
REMOVE - thyroidectomy
DESTROY - High dose radio iodine
KEEP ASLEEP - long term thyroxine
79
What suggests poor prognosis
<16 or >45
Tumour size
Spread outside capsule / mets
80
How do you follow up
Thyroglobulin
| Whole body isotope scan 2-5 weeks after withdrawal of thyroxin
81
What are other cancers
Medulalry
Anoplastic
Lymhpoma
82
Where does medullary arise from and what is it associated with
Parafollicular C cells
Malignant
MEN 2A+B / RET mutation
Raised calcitonin as produces
83
How do you RX
Thyroiectomy
| No RAI as not from thyroid cells
84
Prongosis of anoplastic
```
Aggressive
Locally invasive
Poor
No response to RAI
Rare
```
85
How do you treat lymphoma
RT + chemo
| Rare
86
When is surgery likely and what do you give prior too prevent complications
Once euthyroid
| Potassium iodide to reduce vascularity
87
What are complications of surgery
```
Bleeding
Trachea compression
Laryngeal nerve palsy
Hypocalcaemia
Hypothyroid
```
88
What is important in Hx of lump
```
Any dysphagia / sore throat / hoarseness
B symptoms
Appetite
Hx head or neck radiation
FH
Smoking / alcohol
```
89
What is important in examinatio
Does it move on swallowing
Hard or soft
Irregular or regular
Fixed?
90
What investigation is suspect thyroid origin of lump
TSH
Thyroid Ab
Thyroid USS
FNA
91
How does myxoedema coma present
Severe hypothyroid
Confusion
Hypothermia
Other Sx related to slowing of organs e.g. brady
92
How do you treat
IV thyroid
IV fluid
IV steroid until adrenal insufficiency excluded
Electrolyte imbalance correction
93
What is sick euthyroid syndrome
Seen in hospital in sick patient
Low T3 an T4
TSH low or normal
Cortisol high as stress response
94
How do you Rx
None as will recover when illness recovered
| Recheck in 6-8 weeks
95
How does amiadarone cause hypo and hyperthyroid
```
Hypo = due to high iodine
Hyper Type 1
- Increased hormone synthesis
- Goitre present
Hyper Type 2
- Destruction of gland
- No goitre
- Rx = steroid
```
96
How do you treat destructive or post partum
Symptomatic BB as due to destruction of gland and release of hormones
