thyroid diseases Flashcards
(117 cards)
1
Q
what are the two categories of thyroid diseases
A
primary
secondary
2
Q
what is a primary thyroid disease
A
a disease affecting the thyroid disease
3
Q
what is a secondary thyroid disease, how is it defined
A
hypothalamic or pituitary disease
no thyroid gland pathology
4
Q
what is primary thyroid disease split into
A
goitre or non-goitrous
5
Q
what is hypothyroidism
A
any disorder which causes insufficient secretion of thyroid hormones from the thyroid gland
6
Q
what are the primary goitres causes of hypothyroidism
A
chronic thyroiditis (most common) iodine deficiency drug-induced
7
Q
what would be a cause of chronic thyroiditis
A
Hashimoto’s thyroiditis
8
Q
what drugs cause hypothyroidism
A
amidarone
lithium (anti-psychotics)
9
Q
what are the primary non-goitrous causes of hypothyroidism
A
atrophic thyroiditis
post cancer treatment
congenital developmental defect
10
Q
what are the primary self-limiting causes of hypothyroidism
A
withdrawal of anti-thyroid drugs
subacute thyroiditis
post-partum thyroiditis
11
Q
what are the common symptoms of hypothyroidism
A
peri-orbital puffiness pale, cool skin pitting oedema vitiligo cold intolerance hyperlipidaemia (causing many cardiac issues) low HR decreased appetite weight gain hyperprolactinaemia
12
Q
what thyroid hormone levels would you expect in PRIMARY hypothyroidism
A
high TSH
low T3 &T4
13
Q
what thyroid hormone levels would you expect in SECONDARY hypothyroidism
A
Low or normal TSH
low T3 & T4
(all low)
14
Q
what auto antibodies are associated with hypothyroidism, what condition do they suggest
A
anti-TPO = autoimmune hypothyroidism
15
Q
what is the treatment of hypothyroidism
A
levothyroxine
young = 50-100 micrograms daily
old = 25-50 micrograms daily
16
Q
why are elderly patients started on a lower dose of levothryoxine
A
due to the risk of cardiac ischaemia
17
Q
what is myxoedema
A
severe hypothyroidism
18
Q
who is typically affected by myxoedema
A
elderly women with long-standing but unrecognised/untreated hypothyroidism
19
Q
what are the ECG symptoms of myxoedema
A
heart block
t wave inversion
prolonged QT interval
20
Q
what are the symptoms of myxoedema
A
unusual ECG
bradycardia
type 2 resp failure
co-existing adrenal failure (10%)
21
Q
what is the treatment of myxoedema
A
passively rewarm cardiac monitoring monitor fluid balance broad spectrum antibiotics give thyroxine cautiously give hydrocortisone until adrenal failure has been ruled out
22
Q
what is autoimmune hypothyroidism also known as
A
hashimoto’s thyroiditis
23
Q
what is the most common cause of hypothyroidism in the western world
A
hashimoto’s thyroiditis
24
Q
what is hashimoto’s thyroiditis
A
gradual failure of thyroid function due to autoimmune destruction of the thyroid gland resulting in reduced thyroid hormone production
25
what is diagnostic of hashimoto's thyroiditis
positive TPO autoantibodies
26
when would you treat subclinical hypothyroidism
if pregnant
| if TSH >10
27
what is hyperthyroidism
overactivity of the thyroid gland which leads to thyrotoxicosis
28
what is thyrotoxicosis
clinical, physiological, and biochemical state arising when the tissues are exposed to excess thyroid hormone
29
what diseases cause excess thyroid stimulation which leads to hyperthyroidism
graves disease
thryoid cancer (rare)
thyroid nodules
30
what causes thyrotoxicosis without hyperthyroidism
thyroiditis
| over-treatment with levothyroxine
31
what are the symptoms of hyperthyroidism
```
palpitations/ AF
tremor
sweating
anxiety/irritable
frequent, loose stools
eye problems = graves
weight loss
increased appetite
intolerance to heat
```
32
what thyroid hormone levels would you expect in PRIMARY hyperthyroidism
low TSH
| high T3 & T4
33
what thyroid hormone levels would you expect in SECONDARY hyperthyroidism
high or normal TSH
high T3 & T4
(all high)
34
what is the treatment of hyperthyroidism
beta-blocker (propanol)
thyroid suppressant drug
radioiodine
surgery s
35
what is the first line drug treatment of hyperthyroidism
carbimazole
36
what are the contraindications of carbimazole
pregnancy
37
what is the 2nd line drug treatment of hyperthyroidism
propylthiouracil
38
when is surgery indicated in hyperthyroidism
if pressure symptoms are present:
dysphagia, stridor, hoarseness
39
what are the risk with surgery in the treatment of hyperthyroidism
recurrent laryngeal nerve palsy
hypothyroidism
hypoparathyroidism
40
what is thyroiditis
inflammation of the thyroid
41
what are the common causes of thyroiditis
```
hashimotos
post-partum
drug-induced
acute suppurative thyroiditis
de Quervain's
```
42
what is acute suppurative thyroiditis
thyroiditis caused by bacteria
43
what is De Quervain's thyroiditis
thyroiditis caused by a virus
44
what are the investigations of acute suppurative thyroiditis, what would it show
sctintigraphy scan = low uptake though-out
45
what are the symptoms of acute suppurative thyroiditis
neck tenderness
fever
other viral symptoms
46
what is the treatment of acute suppurative thyroiditis
self-limiting
47
when is subclinical hyperthyroidism often seen
multinodular goitre
48
what is subclinical hyperthyroidism associated with
AF
| osteoporosis
49
when would you treat subclinical hyperthyroidism
if TSH <0.1
| if there is co-existing fracture, AF or osteoporosis
50
what is graves disease
autoimmune disease causing hyperthyroidism
51
what age range is affected by graves disease
20-50
52
what are the SPECIFIC symptoms of graves disease
pre-tibial myxoedema
diffuse goitre
thyroid bruits (if goitre is large)
graves eye disease
53
what is the treatment of graves eye disease
lubricants, steroids, radiotherapy, surgery (depends on severity)
54
what thyroid hormone levels would you expect in graves disease
low TSH
| high T3 & T4
55
what other investigations would you do in graves disease
hypercalcaemia
high all phos
TSH receptor antibody (TRAb) present
imaging
56
when is imaging unnecessary in graves disease
if TRAb is present
57
what is the treatment of graves disease
carbimazole
radioiodine
surgery
58
what is the 1st line treatment in relapse of graves disease
radioiodine
59
when is radioiodine contraindicated
pregnancy
| active graves eye disease
60
what is thyroid storm/crisis
severe hyperthyroidism
61
who does thyroid crisis usually affect
hyperthyroid patients with an acute infection/illness or recent thyroid surgery
62
what are the symptoms of thyroid crisis
exaggerated reflexes
hyperthermia
respiratory and cardiac collapse
63
what is the treatment of thyroid crisis
```
Lugol’s iodine
Glucocorticoids
PTU
Beta-blockers
Fluids
Monitoring
```
64
what are the types if congenital thyroid disease
primary
| secondary
65
give examples of primary congenital thyroid disease
dysplastic gland +/- abnormal site
| error in thyroid hormone metabolism
66
give examples of secondary congenital thyroid disease
congenital pituitary disease
| hypopituitarism
67
what are the symptoms of congenital thyroid disease
```
delayed jaundice
poor feeding but normal wight
hypotonia
- umbilical hernia
- constipation
```
68
what are the investigations of congenital thyroid disease
guthrie test
TSH levels
T4 level
69
what can a delay in treatment of congenital thyroid disease cause
cretinism
70
why does amidarone cause abnormal thyroid function hormone levels
it inhibits DIO1 which increases free T4, decreased T3 and leave TSH at normal levels
71
what does amidarone cause
hypothyroidism in iodine rich areas
| Hyperthyroidism in iodine deficient areas
72
what is a goitre
any enlargement of the thyroid gland
73
what causes a goitre
lack of dietary iodine
| reduced T3 & T4
74
what are the investigations of a goitre
TSH levels
| Ultrasound guided FNA
75
when would you do an isotope scan in goitre
if TSH is suppressed
76
what does a midline goitre suggest
thyroid
thyroglossal cyst
dermoid cyst
77
what are the types of goitres
diffuse/solitary
| multi-nodular
78
what is the cause of a multi-nodular goitre
evolution from a long-standing, simple goitre
variation of response of follicular cells to external stimuli
79
what is the treatment of a goitre
```
nothing = asymptomatic
radioiodine = significant hyperthyroid issues
surgery = causing structural problems
```
80
what would make you suspect a thyroglossal cyst
moves when tongue is stuck out
81
describe a dermoid cyst
soft and non-fluctuant
82
what is the cause of a brachial cyst
which arises in the upper part of the anterior triangle.
83
where does a brachial cyst arise
upper part of the anterior triangle
84
what is the investigation for brachial cyst
FNA for cholesterol crystals
85
what is the description of a brachial cyst
half-filled hot water bottle
86
what is the description of cystic hygroma
lymph filled and so are Transilluminate
87
what is follicular adenoma
discrete solitary mass composed of neoplastic thyroid follicles and encapsulated by a surrounding collagen cuff.
88
what causes thyroid adenoma
mutations of TSHR signalling pathway
| mutant RAS or PIK3CA
89
what is the most common thyroid malignancy
papillary carcinoma
90
how does papillary carcinoma present
solitary nodule within the thyroid, may be cackled by psammoma bodies
91
what is the treatment of papillary carcinoma
thyroidectomy
92
what is the follow up after treatment of papillary carcinoma
TSH 0.4-4 (lower levels of normal are preferred)
check Thyroglobulin
TSH/Tg measured every 6 months for 1st 5 years and then annually for the next 5 years
93
what is the 2nd most common thyroid cancer
Follicular Carcinoma
94
at what age does Follicular Carcinoma occur
40-50s (later than papillary carcinoma)
95
at what age does papillary cancer arise
30-40
96
what is the treatment of Follicular Carcinoma
minimally invasive = thyroid lobectomy
| significant invasion = total thyroidectomy
97
what is thyroglobulin
precursor of T4/T3 made by follicular epithelial cell
98
what is the follow up after the treatment of Follicular Carcinoma
TSH 0.4-4 (lower levels of normal are preferred)
check Thyroglobulin
TSH/Tg measured every 6 months for 1st 5 years and then annually for the next 5 years
99
what is the cause of Follicular Carcinoma
iodine deficiency
| mutation in PI3K (RAS family)
100
what is the cause of papillary carcinoma
ionising radiation
| activation of MAP kinase pathway
101
what does cells does Medullary Thyroid Carcinoma arise from
C cells aka parafollicular cells
102
what cells does follicular carcinoma arise from
follicular cells
103
what cells does papillary carcinoma arise from
follicular cells
104
what causes Medullary Thyroid Carcinoma in young people
MEN2
105
what causes Medullary Thyroid Carcinoma on adults
sporadic mutation = solitary nodule
| familial medullary carcinoma = bilateral/multi-centric nodule
106
what can be secreted in Medullary Thyroid Carcinoma
calcitonin
107
what can secretion of calcitonin in Medullary Thyroid Carcinoma cause
amyloid deposition
108
what are the investigations of Medullary Thyroid Carcinoma
FNA = amyloid and high calcitonin
| 24hr urinary metanephrines = MEN2
109
how does hCG impact thyroid hormones
causes an increases thyroxine with surpasses TSH
110
what thyroid condition does hCG cause thyroid hormones to mimic
hyperthyroidism
111
why is hypothyroidism common in pregnancy
plasma protein binding increases causing an increased demand in thyroid hormones
112
what should you do with a pregnant patient who has pre-existing hypothyroidism
increased thyroxine dose by 25mcg
| check thyroid function test monthly, then twice monthly after 20 weeks
113
what TSH level should be aimed for in a pregnant patient who has pre-existing hypothyroidism
TSH <3
114
how can you tell the difference between hyperthyroidism in pregnancy and hyperemesis
TRAb antibody is present in 3rd trimester in hyperthyroidism
115
what is the treatment for a pregnant patient who has pre-existing hyperthyroidism
treat symptoms if they are on going by 20 weeks
| low-dose antithyroid drugs
116
what antithyroid drugs are used to treat a pregnant patient who has pre-existing hyperthyroidism
1st trimester = propylthiouracil
| 2nd/3rd trimester = carbimazole
117
what is postpartum thyroiditis
For 1-4 months postpartum, women may become transiently thyrotoxic before experiencing hypothyroidism
