Enlarged palpable thyroid gland, which moves on swallowing

Aetiology

• May be a benign disorder but is also associated with several thyroid diseases, including iodine deficiency, Hashimoto’s thyroiditis, and some of the causes of hyperthyroidism

Pathophysiology

• Reduced T3/T3 production causes a rise in TSH, stimulating gland enlargement
• This may maintain euthyroid state or if compensation fails there will be goitrous hypothyroidism

Diffuse goitre

Aetiology

• Physiological goiter - puberty, pregnancy
• Autoimmune thyroid disease - Hasimoto's thyroiditis, Grave's disease thyrotoxicosis
• Endemic - iodine deficiency +/- ingestion of goitrogens (chemicals which exaggerate the effects of iodine deficiency)
• Inflammation - acute (de Quervain's) thyroiditis
• Sporadic
  • 4:1 females, usually during puberty/YA
  • Most cases have no clear cause
  • Some associated with ingestion of substances limiting T3/T4 production or inborn errors of metabolism (dyshormonogenesis)

Clinical features

• Entire thyroid gland swells and is smooth to the touch
• Usually euthyroid, if not may be symptoms of hyper/hypothyroidism
• Present with mass effects
  • Cosmetic
  • Compression of the trachea → exertional dyspnoea and, in severe cases, stridor or wheezing
  • Compression of the oesophagus  → dysphagia
• In children dyshormonogenesis may cause cretinism

Investigations

• Thyroid function tests: T3/T4 normal, TSH high or upper limit of normal