Flashcards in Clinical (Week 3 - Thyroid and Adrenal) Deck (147):
What is the most common kind of thyroid cancer?
What type of thyroid cancer has the worst prognosis?
What does differentiated mean in terms of cancer?
Difficult to tell between normal thyroid cells and the cancer cells
What do most thyroid cancers take up and secrete?
What drives differentiation thyroid cancers?
What populations have a decreased risk of differentiated thyroid cancer?
What is differentiated thyroid cancer strongly associated with?
What is differentiated thyroid cancer weakly associated with?
Chronically increased TSH
What do most differentiated thyroid cancers present with?
How does papillary thyroid cancer spread and where to?
What is papillary thyroid cancer associated with?
In what areas is the incidence of follicular carcinoma increased?
Regions of relative iodine deficiency
How does follicular carcinoma spread?
What is the gold-standard investigation for a suspected thyroid cancer?
Which of the following is not a negative clinical predictor of malignancy:
- New nodule age 50
- Nodule increasing in size
- Lesion >4cm
- Heavy smoker
- Head/Neck irradiation
- Vocal cord palsy
What is the first line management for thyroid cancer?
- Thyroid lobectomy with isthmusectomy
- Subtotal thyroidectomy
- Total thyroidectomy
How can we calculate the post-operative risk in thyroid cancer?
A - Age
M - Metastases
E - Extend of primary tumour
S - Size of primary tumour
Which of the following is not a feature of an AMES high risk individual:
- Age 5cm
When is a thyroid lobectomy with isthmusectomy used?
Papillary microadenoma (
What is the gold-standard operative management for thyroid cancer?
What is important in the post-operative care in thyroid cancer?
Check calcium within 24 hours:
- All parathyroid glands may be removed
Replace calcium is corrected calcium
What must post-operative patients be discharged with following a sub-total thyroidectomy?
T4 (or T3)
When is whole body iodine scanning used and what must be done beforehand?
Patients who had a sub-total/total thyroidectomy:
- 3-6 months post-op
T4 stopped 4 weeks prior; T3 stopped 2 weeks prior
What level of TSH would give the best results for a whole body iodine scan?
What is the procedure for whole body iodine scanning?
2-4mCi (75-150MBq) I-131 capsule on the Tuesday
Imaging on Friday
What happens if the uptake on whole body iodine scanning is >0.1% of ingested activity?
Thyroid Remnant Ablation (the following Tuesday)
What is the process of thyroid remnant ablation?
Admitted to a lead-lined rooms with mains sewage
2 or 3 GBq capsule of I-131 administered
What are some side effects of thyroid remnant ablation?
Sialadenitis (Salivary gland inflammation)
What precautions must be taken during thyroid remnant ablation?
Disposable cutlery and sheets
Store patients clothing
Little/no nurse or visitor contact
When is a patient discharged after thyroid remnant ablation?
When count rate
What are the aims of thyroid remnant ablation?
What is thyroglobulin used as a marker for?
What should also be measured alongside thyroglobulin? Apart from after ablation when should it be measured?
- Not all patient tumours secrete Tg
What are some long-term complications of thyroid remnant ablation?
Small increase in risk of acute myeloid leukaemia
What bounds the anterior neck triangle?
Anterior border of SCM laterally
What bounds the posterior neck triangle?
Posterior border of SCM anteriorly
Anterior border of trapezius laterally
What are some causes of a superficial neck swelling?
What position should a patient be in for examining their neck?
Seated in good light
Neck partly extended
What can cause cervical lymphadenopathy?
What systemic symptoms can be present and what might these indicate in regard to cervical lymphadenopathy?
- Hodgkin's Lymphoma
If examining a thyroid swelling, what term is used to describe the following findings:
- One lump
- More than one lump
- Multinodular goitre
What causes of midline swellings move on swallowing?
What causes of midline swellings move on sticking out the tongue?
Why might a thyroglossal cyst become infected?
It contains lymphatics
What age group do thyroglossal cysts present in?
A 16 year old boy present with a soft, non-fluctuant midline neck swelling. On examination it doesn't move with swallowing or on sticking out the tongue.
In what region of the neck does a branchial cyst present?
Upper anterior triangle
What is a branchial cyst?
Persisting second branchial arch
How could a branchial cyst be described?
Half-filled hot water bottle
On FNA, what would be seen in a branchial cyst?
What happens if a branchial cyst fistulates?
Saliva leaks out anterior to SCM
What are other causes of anterior neck swellings?
Carotid body tumour
A 9 month old child presents with a large neck swelling in their posterior neck triangle. On examination it transilluminates.
What is a cystic hygroma filled with?
Why are stones more common in the submandibular glands?
Saliva is more mucous-y
What is the most common pathology affected the parotid gland?
Why are stones less common in the parotid gland?
Saliva is more serous
On FNA what do the following mean and what should be done after:
- Thy 1
- Thy 2
- Thy 3
- Thy 4/5
- Repeat FNA
- Repeat FNA in 6 months
- Thyroid lobectomy
- Total thyroidectomy
What T4/T3 + TSH levels would be expected in each of the following:
- Pituitary gland failure
- T4/T3 high
- TSH low
- T4/T3 low
- TSH high
- TSH high
- T4/T3 high
Pituitary gland failure:
- TSH low
- T4/T3 low
What does myxoedema mean in terms of hypothyroidism?
Severe hypothyroidism can cause a myxoedema coma
What cause of hypothyroidism present with a goitre?
What drugs can induce hypothyroidism?
What can cause a self-limiting hypothyroidism?
After withdrawal of suppressive therapy
Thyroiditis with transiet hypothyroidism
What are some hypothalamic causes of secondary hypothyroidism?
What are some pituitary causes of secondary hypothyroidism?
Isolated TSH deficiency
What are some risk factors for autoimmune thyroiditis?
FHx of thyroid/autoimmune disease
What is autoimmune hypothyroidism characterised by?
Thyroid Peroxidase Antibodies (in blood)
- T cell infiltrate
Which of the following is not a hair and cutaneous sign of hypothyroidism:
- Dull face
- Periorbital puffiness
- Thickened hair
Thickened hair (It is actually coarse and sparse)
In hypothyroidism, are patient's intolerant to the cold or the heat?
What are some cardiac features of hypothyroidism?
Reduced heart rate
Worsening of CHF
What other biochemical results might be seen in hypothyroidism?
Macrocytosis (Increased MVC >100 fL):
- Rule out Vit. B12 deficiency
Increased levels of:
- Cretinine kinase
What TSH receptor antibodies are seen in:
- Grave's Disease
- Autoimmune hypothyroidism
What might happen if hypothyroidism is corrected too rapidly?
How is hypothyroidism treated?
- Young patients -> 50-100μg daily
- Elderly with IDH -> 25-50μg daily (Adjusted monthly(
When is TSH checked during hypothyroidism treatment?
2 months after a dose change
- Every 12-18 months
When is thyroxine taken?
When is T3 used?
If T4 not tolerated
What do you do to a patient's T4 dose if they are pregnant?
Increase it by 25-50%
How do you monitor the success of treatment in:
- Primary hypothyroidism
- Secondary hypothyroidism
An elderly woman presents to A&E with reduced consciousness. She has long-standing hypothyroidism that is poorly managed. On ECG there is bradycardia, evidence of heart block and some QT-prolongation. An ABG is taken, her PaO2 is 7.2kPa, her PaCO2 is 11.5kPa and her pH is 7.29.
How is a myxoedema coma treated?
- Slowly increase body temperature
- Monitor ECG
- Broad spectrum antibiotics
- Thyroxine cautions (hydrocortisone)
What are some common causes of hyperthyroidism?
Autoimmune (Grave's Disease)
- Toxic nodule -> Adenoma
What is seen on scintigraphy if the patient has Grave's disease?
Smooth symmetrical goitre:
- High uptake
What are ophthalmology features of Grave's disease?
Chemosis (Swollen conjunctiva)
What causes the ophthalmology features in Grave's disease?
How can ophthalmology features be treated?
What patient's tend to suffer from nodular thyroid disease?
How does a nodular thyroid appear on scintigraphy?
Assymetrical (High uptake)
How does a thyroid storm present?
Respiratory and cardiac collapse
How do you treat a thyroid storm?
How is hyperthyroidism treated?
How are oral medications used in Grave's?
Started at high dose:
- Decrease over 12-18 months
- Then stop
What can hyperthyroidism treatment cause?
What hyperthyroidism treatment is preferred in pregnancy?
Which of the following is not a precaution in the use of radio-iodine for the treatment of hyperthyroidism:
- Avoid contact with kids and pregnant women
- No bed-sharing
- Avoid pregnancy for a month
- High risk of hypothyroidism
Avoid pregnancy for a month:
- Should be avoided for 6 months
A 31 year old woman present with a sore swelling in her neck and a fever. She says she had the flu a couple of weeks ago. Her TSH is high and T4 is low. There is low uptake on Scintigraphy.
De Quervain's/Subacute Thyroiditis
What hormone does the ovum produce?
What hormone does the corpus luteum produce?
What hormone is tested for by a pregnancy test?
Human Chorionic Gonadotropin
What hormones does the placenta produce?
Human Placental Lactogen (hPL)
What is the pathogenesis behind gestational diabetes?
1. Increased levels of progesterone + hPL
2. Insulin resistance in mum
3. Increased blood glucose
4. Gestational DM (Late 2nd -> 3rd trimester)
What neonatal complications are at a higher incidence in diabetes?
CNS defects (5x):
- Spina Bifida
Caudal regression syndrome (200x)
Ureteric duplication (20x)
What does maternal hyperglycaemia result in?
> Foetal hyperinsulinaemia
> Macrosomia (birth weight > 4kg)
> Neonatal hypoglycaemia
What does insulin act as in the 3rd trimester?
A major growth factor
What drugs should be avoided in diabetes during pregnancy?
- Use labetalol, Nifedipine or Methyl dopa instead
What should blood glucose be during pregnancy?
How can good blood glucose be maintained during pregnancy?
How is MODY managed?
How is gestational diabetes managed?
Metformin -> May need insulin
6 week post-natal GTT to ensure resolution
What hormone is very important for foetal development?
What happens to thyroid demand and plasma protein binding during pregnancy?
What hormones are often high in hyperemesis gravidarum?
How does the thyroid meet the increased demand during pregnancy?
Increases in size
Increases fT4 production
As soon as pregnancy is expected, what must be done to the thyroxine dose for patients suffering from hypothyroidism?
Increase the dose by 25μg
How often are TFTs checked during pregnancy?
Monthly for 1st 20 weeks
Every 2 months until term
What should the TSH aims be during pregnancy?
Untreated hypothyroidism increases the incidence of what complications during pregnancy?
What are some features of gestational hCG-associated thyrotoxicosis?
- Increased hCG -> Decreased TSH
Resolves by 20 weeks gestation
Only treat is persisting longer than 20 weeks
How does hCG cause an increased release of T4?
Very similar structure to TSH:
- Both two chain peptides
> α-chains identical
> β-chains different
How can we treat hyperthyroidism during pregnancy?
β-blockers if needed
LOW DOSE anti-thyroid drugs:
- Propylthiouracil during 1st trimester
- Carbimazole during 2nd + 3rd trimester
What can carbimazole cause during pregnancy?
Choanal and oesophageal atresia
A woman presents do the GP with a small swelling in her neck. You find out she gave birth 3 months ago. On examination of the neck, the thyroid is slightly swollen and isn't tender. TFTs show a reduced T4 and slightly raised TSH.
What does CRH stimulate?
Release of ACTH from anterior pituitary
What does TRH stimulate?
TSH release from anterior pituitary
What does GnRH stimulate?
LH/FSH release from anterior pituitary
What does GHRH stimulate?
Release of GH from anterior pituitary
What effect does dopamine have?
Inhibits prolactin release
What is Cushing's Syndrome?
What effect does Cushing's syndrome have on protein and how does this manifest?
Protein is lost:
- Myopathy -> Wasting
- Osteoporosis -> Fractures
- Thin skin
What does the excess mineralocorticoid cause in Cushing's?
What does the excess androgen cause in Cushing's?
What distinguishes Cushing's from obesity?
Frontal balding in women
What are some screening tests for Cushing's?
Overnight 1mg PO dexamethasone suppression:
- Cortisol Normal
- Cortisol >100nmol/L -> Abnormal
Urine free cortisol (24hr):
What is the definitive test for diagnosing Cushing's?
Two day 2mg/day low dose DST:
- Cortisol No Cushing's
What can cause an ectopic production of ACTH?
Small-cell lung cancer
How is pituitary Cushing's (Cushing's disease) treated?
Hypophysectomy + External radiotherapy if it recurs
How is adrenal Cushing's treated?
How is ectopic Cushing's treated?
What is the drug treatment for Cushing's and when is it used?
- If other treatments fail
- While waiting for radiotherapy to work
How does pan-hypopituitarism present?
What local brain tumours can cause hypopituitarism?
What granulomatous disease can cause hypopituitarism?
What effects does growth hormone have in adults?
Reduces abdominal fat
- Muscle mass
Improves cardiac function
Reduces cholesterol and LDL
Increases bone density
What are some risks of testosterone replacement?
What dose the following stand for in terms of a familial presentation of cranial diabetes insipidus DIDMOAD?
How is diabetes insipidus diagnosed?
Water deprivation test:
- Urine osmolarity will fall to less than 300mOsm/kg
- Cranial DI (Urine osmolarity rises by over 50%)
- Nephrogenic DI (Less than 50% rise)