hyperthyroidism, hypothyroidism and thyroiditis

Question 1

what does primary thyroid disease mean?

Answer 1

-a disease affecting the thyroid gland itself

Question 2

what are the levels of T4, T3 and TSH like in primary hypothyroidism?

Answer 2

T4/T3= too low
TSH= high

Question 3

what are T3, T4 and TSH levels like in primary hyperthyroidism?

Answer 3

T3 + T4= high

TSH= low

Question 4

what are T3, T4 and TSH like in secondary hypothyroidism?

Answer 4

T3 + T4= low

TSH= low (or ‘normal’)

Question 5

what are T3, T4 and TSH like in secondary hyperthyroidism?

Answer 5

T3 + T4= high

TSH= high (or normal)

Question 6

what is myxoedema?

Answer 6

-severe hypothyroidism and is a medical emergency

Question 7

what is pretibial myxoedema?

Answer 7

a rare clinical sign of Graves’ disease (an autoimmune disease which results in hyperthyroidism)

Question 8

who is hypothyroidism more common in?

Answer 8

• women
• white population
• incidence is higher in areas of high iodine intake

Question 9

what is the most common cause of hypothyroidism in western world?

Answer 9

autoimmune (hashimotos)

Question 10

what increases risk of getting hashimotos?

Answer 10

-family history of autoimmune or thyroditis

Question 11

what most common antibodies found in Hashimoto’s?

Answer 11

thyroid peroxidase antibodies

Question 12

what can occur to hair and skin in hypothyroidism?

Answer 12

• coarse, sparse hair
• dull, expressionless face
• periorbital puffiness
• pale cool skin that feels doughy to touch
• vitiligo may be present
• hypercarotenaemia

Question 13

how may a patients tolerence to temperature change if they have hypothyroidism?

Answer 13

-they may develop cold intolerance

Question 14

what are some cardiac clinical features of hypothyroidism?

Answer 14

• reduced heart rate
• cardiac dilatation
• pericardial effusion
• worsening of heart failure

Question 15

what affect does hypothyroidism have on lipidaemia?

Answer 15

it can cause hyperlipidaemia

Question 16

what affect does hypothyroidism have on appetite and weight?

Answer 16

• decreased appetite

- increased weight gain

Question 17

what are some GI clinical features of hypothyroidism?

Answer 17

• constipation
• megacolon and intestinal obstruction
• ascites

Question 18

what are some resp clinical features of hypothyroidism?

Answer 18

• deep hoarse voice
• macroglossia
• obstructive sleep apnoea

Question 19

what are some neurological/CND clinical features of hypothyroidism?

Answer 19

• decreased intellectual and motor activities
• depression, psychosis and neuro psychiatric
• muscle stiffness, cramps
• peripheral neuropathy
• prolongation of the tendon jerks
• carpal tunnel syndrome
• decreased visial acuity

Question 20

what are some gynae/reproductive clinical features of hypothyroidism?

Answer 20

• menorhagia
• later oligo or amenorrhoea
• hyperprolactaemia

Question 21

what causes hyperprolactaemia?

Answer 21

high TRH (once TRH is lowered it can be reversed)

Question 22

what is treatment for hypothyroidism in younger patients?

Answer 22

-start levothyroxine (T4) at 50-100 micrograms daily

check TSH 2 months after any dose change and once stabilised check TSH every 12-18 months

Question 23

what is treatment for hypothyroidism in older patients?

Answer 23

in elderly patients with a history of IHD:
-start levothyroxine (T4) at 25 to 50 micrograms daily, adjust every 4 weeks according to response

-TSH should be checked 2 months after any dose change and once stabilised TSH should be checked every 12-18 months

Question 24

when should levothyroxine (T4) be taken?

Answer 24

• before breakfast (on empty stomach)

- doesn’t work if taken with PPI, iron tablets and calcium tablets as they impair the absorption

Question 25

what should happen to dose of levothyroxine to a pregnant patient with hypothyroidism?

Answer 25

dose of levothyroxine should be increased by 25-50%

Question 26

who does myxoedema coma usually affect?

Answer 26

-elderly women with long standing but frequently unrecognized or untreated hypothyroidism

Question 27

what are the signs of a myxoedema coma?

Answer 27

ECG: bradycardia, low voltage complexes, varying degrees of heart block, T wave inversion, prolongation of the QT interval Type 2 respiratory failure: hypoxia, hypercarbia, respiratory acidosis In 10% of patients there is co existing adrenal failure

Question 28

what is the treatment for myxoedema coma?

Answer 28

- ICU - passive rewarm (aim for slow rise in body temp) - cardiac monitoring for arrhythmias - close monitoring of urine output. fluid balance, central venous pressure, blood sugars, oxygenation - broad spectrum antibiotics - thyroxine cautiously (hydrocortisone)

Question 29

what is thyrotoxicosis?

Answer 29

-a clinical, physiological and biochemical state arising when tissues are exposed to excess thyroid hormone

Question 30

what are cardiac signs/symptoms in thyrotoxicosis?

Answer 30

- palpitations - AF - cardiac failure (very rare) - tremor - sweating

Question 31

what are CNS signs/symptoms in thyrotoxicosis?

Answer 31

- anxiety - nervousness - irritability - sleep disturbances

Question 32

what are GI signs/symptoms in thyrotoxicosis?

Answer 32

-frequent, loose bowel movements

Question 33

what are vision signs/symptoms in thyrotoxicosis?

Answer 33

- lid retraction - double vision - proptosis

Question 34

what are hair and skin signs/symptoms in thyrotoxicosis?

Answer 34

brittle, thing hair | rapid fingernail growth

Question 35

what are reproductive signs/symptoms in thyrotoxicosis?

Answer 35

-menstrual cycle changes (including lighter bleed and less frequent periods)

Question 36

what are the changes in muscles in thyrotoxicosis?

Answer 36

-muscle weakness (especially in thigha and upper arms)

Question 37

what are the changes in weight in someone with thyrotoxicosis?

Answer 37

weight loss even though there's increased apetite

Question 38

what is a patients with thyrotoxicosis tolerance to temperature like?

Answer 38

-they have an intolerance to heat

Question 39

who does Grave's disease usually affect?

Answer 39

younger 20-50 years

Question 40

what are some clinical signs/features of Grave's?

Answer 40

- pretibial myxoedema - thyroid acropachy - thyroid bruit - Grave's eye disease

Question 41

who does nodular thyroid disease typically affect?

Answer 41

-older patients

Question 42

what tests are done if a patient has suspected nodular thyroid disease?

Answer 42

- increase T4/3 - decrease TSH - antibody negative (TRAb) - thyroid US - scintigraphy: high uptake

Question 43

what is the first line treatment for hyperthyroidism?

Answer 43

1st line= Carbimazole once daily

Question 44

what is the first line treatment for someone in their first trimester of pregnancy?

Answer 44

Propylthiouracil (PTU) twice daily

Question 45

side effects of using carbimazole in pregnancy?

Answer 45

-risk of aplasia cutis in early pregnancy

Question 46

side effects of propylthiouracil (PTU)

Answer 46

1:10,000 risk of liver failure

Question 47

what type of drug is carbimazole?

Answer 47

ATD (antithyroid drug)

Question 48

what are side effects of ATDs (carbimazole)?

Answer 48

- 1 to 5% will develop allergic reaction (rash, urticaria, arthralgia) - cholestatic jaundice, increase liver enzymes, fulminant hepatic failure (PTU) - agranuloytosis

Question 49

what is agranulocytosis?

Answer 49

-a life-threatening blood disorder when the body cannot make enough of a type of white blood cell called neutrophils

Question 50

what should the patient be warned about and how before starting carbimazole?

Answer 50

- warned about the side effect of agranulocytosis - warn patient verbally and in writing to stop drug and have urgent FBC checked in event of fever, oral ulcer or oropharyngeal infection

Question 51

when should a patient get an urgent FBC and stop taking carbimazole?

Answer 51

in event of : - fever - oral ulcer - oropharyngeal infection

Question 52

when is risk of getting agranulocytosis highest when on carbimazole?

Answer 52

-in first 6 weeks

Question 53

what treatment is good for immediate symptomatic relief of thyrotoxic symptoms in patients with hyperthyroidism?

Answer 53

BB (propanolol)

Question 54

what is 1st line treatment of relapsed Graves' disease ?

Answer 54

radioiodine

Question 55

what is 1st line treatment of nodular thyroid diseases?

Answer 55

radioiodine

Question 56

when is radioiodine contraindicated?

Answer 56

- in pregnancy | - relatively in active thyroid eye disease

Question 57

what is a high risk when treating Grave's patients with radioiodine?

Answer 57

-high risk of hypothyroidism

Question 58

when is a thyroidectomy the choice of treatment in hyperthyroidism?

Answer 58

-when radioiodine is contraindicated

Question 59

what risks does a thyroidectomy bring?

Answer 59

- recurrent laryngeal nerve palsy - hypothyroidism - hypoparathyroidism

Question 60

what is thyroiditis?

Answer 60

inflammation of the thyroid

Question 61

who is subacute thyroiditis typically found in?

Answer 61

-females ages 20-55

Question 62

what may trigger subacutre thyroitisis?

Answer 62

-viral infection

Question 63

what are some associated symptoms of subacute thyroiditis?

Answer 63

- neck tenderness - fever - and/or other viral symptoms

Question 64

what are the investigations for subacute thyroiditis?

Answer 64

scintigraphy scan (low uptake throughout)

Question 65

what are some causes of thyroiditis?

Answer 65

- hashimotos - de quervain's/subacute - post partum - drug induced (amiodarone, lithium) - radiation - acute suppurative thyroiditis (bacterial)

Question 66

what is the treatment for subacute thyroiditis?

Answer 66

-its usually self limiting (few months)

Question 67

what is subclinical al thyroid disease?

Answer 67

-abnormal TSH with normal thyroid hormone levels

Question 68

what would T3, T4 and TSH be like in subclinical hypothyroidism?

Answer 68

``` TSH= increase T4/T4= the same ```

Question 69

what would T3, T4 and TSH be like in subclinical hyperthyroidism?

Answer 69

``` TSH= lower T3/T4= the same ```

Question 70

when is treatment advised in subclinical hypothyroidism?

Answer 70

- when TSH>10 | - if pregnancy

Question 71

when is treatment advised in subclinical hyperthyroidism?

Answer 71

- when TSH<0.1 | - or if there's coexisting osteoporosis/fracture or AF

Question 72

what increases risk of getting sunclinical hypothyroidism?

Answer 72

-if TPO antibody positve

Question 73

what increases risk of getting sunclinical hyperthyroidism?

Answer 73

- multinodular goitre | - if patient has Afib or osteoporosis

Question 74

what is non thyroidal illness also known as?

Answer 74

sick euthyroid syndrome

Question 75

who is non thyroidal illness commonly seen in?

Answer 75

-unwell, hospitalised patients

Question 76

what are TSH levels like in non thyroidal illness ?

Answer 76

TSH typically supressed initially and then rises during recovery

Question 77

who os postpartum thyroiditis more common in?

Answer 77

-type 1 diabetic women

Question 78

how does postpartum thyroiditis present?

Answer 78

- temporary overactive thyroid and after a few weeks becomes under active - occurs after birth - however not all women with postpartum thyroiditis will go through both phases

Question 79

what is De Queverain's thyroiditis?

Answer 79

-thyroiditis caused by a viral infection such as mumps or flu

Question 80

how does De Queverain's thyroiditis present?

Answer 80

- initially hyperthyroidism and then after a couple weeks can become hypo - this can resolve spontaneously or hypothyroidism may become permenant - fever - pain in neck, jaw or ear