Hypothyroidism (Hashimoto's Thyroiditis)

Question 1

Epidemiology and risk factors

Answer 1

Epidemiology:
Females
Middle Age (30-50)
Post-partum
Risk increases with Age

Risk factors:
Family history
History of autoimmunity: e.g. pernicious anaemia, T1DM, coeliac disease
Genetic disorders: Turner and Down syndrome
Chest or neck irradiation
Thyroidectomy or radioiodine

Question 2

Aetiology

Answer 2

Main worldwide cause: Iodine deficiency
Most common cause in areas with no iodine deficiency/developed world: autoimmune thyroiditis = Hashimoto’s thyroiditis
De Quervain’s thyroiditis
Post-partum thyroiditis
- Same mechanism as Hashimoto’s BUT Acute (presents during pregnancy) and resolves by itself within 1 year of Sx
Drugs: Amiodarone
Hypo-pituitism

Question 3

Pathophysiology (primary and secondary)

Answer 3

Primary - Autoimmune disorder (Hashimoto’s) = Anti-TPO Ab or Iodine deficiency
Secondary = Pathology effecting pituitary gland (pituitary apoplexy) or tumour compressing the pituitary gland

Question 4

Signs

Answer 4

Bradycardia
Slow reflexes
Cold hands
Goitre (in Hashimoto’s and Iodine Deficiency)
Pretibial Myxoedema

Question 5

Symptoms

Answer 5

Cold intolerance, Constipation,
Weight gain,
Lethargy,
Amenorrhoea

Question 6

Diagnosis

Answer 6

FIRST LINE: TFTs =
High TSH, Low T3/4 = Primary
Low TSH, Low T3/T4 = Secondary
High TSH, Normal T3/4 = subclinical hypothyroid
Anti-TPO Ab
Inflammatory markers = high in De Quervain’s
Typically, Anaemic (can be all types - macrocytic, normocytic, macrocytic

Question 7

Treatment

Answer 7

FIRST LINE: LEVOTHYROXINE
(T4)
+ Iron and calcium carbonate every 4 hours to reduce absorption

Question 8

Levothyroxine SE

Answer 8

If dose too high cause iatrogenic hyperthyroidism

Question 9

BRADYCARDIC

Answer 9

Bradycardia
Reflexes
Ataxia
Dry hair/skin
Yawning
Cold hands
Ascites
Round face
Defeated demeanour
Immobile
Congestive Heart Failure

Question 10

hashimOtOs

Answer 10

hypOthyroidism
slOw
Older (60-70)