Thyroiditis

Question 1

Define thyroiditis and its 2 main types

Answer 1

Inflammation of the thyroid gland

DeQuervain’s thyroiditis/ subacute granulomatous thyroiditis: acute viral infection of the thyroid gland

Hashimoto’s thyroiditis: Autoimmune disease of the thyroid gland

Question 2

Aetiology of DeQuervain’s thyroiditis

Answer 2

Viral e.g. influenza, adenovirus, mumps, coxsackie, H1N1
Tends to occur after an URTI
HLA-Bw35
Familial cases (HDL-B35)

Question 3

Aetiology of Hashimoto’s thyroiditis

Answer 3

Autoimmune of the thyroid gland with antibodies against thyroperoxidase (TPO), leaving the gland unable to produce T4/T3

Question 4

Symptoms of Thyroiditis

Answer 4

DeQuervain’s:

1. Thyrotoxicosis with viral prodrome (viral like illness, neck pain, fever, myalgia, malaise, pharyngitis)
2. Hypothyroidism
3. Euthyroidism

Hashimoto’s:
Hypothyroidism
Large, firm swelling of the thyroid

Hypothyroidism:
Cold intolerance
Weight gain + increased appetite
Constipation
Bradycardia
Hypotensions
Deepening voice
Depression and tiredness

Question 5

What is a myxoedema coma

Answer 5

Complication of hypothyroidism

Hypothermia
Hypoventilation
Hyponatraemia
HF
Confusion
Coma

Question 6

Signs of Hypothyroidism

Answer 6

DeQuervain’s:
Tender, firm enlarged thyroid gland

Hashimoto’s:
Large, firm swelling of the thyroid gland
Hands: bradycardia, cold
Head/neck/skin: pale and puffy face, goitre, oedema, hair loss, dry skin, vitiligo
Chest: pericardial or pleural effusion
Abdomen: ascites
Neurological: slow relaxation of reflexes, signs of carpal tunnel syndrome

Question 7

Investigations for DeQuervain’s thyroiditis

Answer 7

TFTs: Initially TSH suppressed/undetectable + T3/4 elevated, later TSH normal/raised
Radioactive iodine uptake: very low uptake, typically 1-3%

ESR + CRP: elevated
Antithyroid antibodies: normal/mildly elevated

Fine needle aspiration (not routine): Multi-nucleated giant cells, with a background of degenerated follicular epithelium cells, rare epithelioid granulomas, and mixed inflammatory cells

Question 8

Investigations for Hashimoto’s Thyroiditis

Answer 8

TFTs: TSH raised
Anti-thyroid peroxidase (TPO) antibodies: positive
Anti-Throglobulin (Tg) antibodies: postiive

FBC: mild, normocytic anaemia
U+Es: Hyponatraemia (myxoedema coma)

Question 9

Management for DeQuervain’s thyroiditis

Answer 9

Hyperthyroid

1. Supportive care
2. Thyroid pain and tenderness -> analgesia/corticosteroid
3. Tachycardia/anxiety/tremor -> beta-blocker
4. Severe thyrotoxicosis -> potassium iodide + prednisolone

Hypothyroid
Mild (TSH<10-15): observe + re-assessment. Interference with ADLs -? levothyroxine
Moderate (TSH>15): levothyroxine PO

Question 10

Complications of Thyroiditis

Answer 10

DeQuervain’s
Thyroid storm
Long-term hypothyroidism

Hashimoto’s:
MALT lymphoma
Myxoedema coma
Hypothyroidism

Question 11

Prognosis for Thyroiditis

Answer 11

DeQuervain’s: complete and spontaneous recovery in >90% of patients, while up to 10% required permanent levothyroxine placement. Low recurrence rate

Hashimoto’s: lifelong therapy required, generally excellent prognosis