patterns of thyroid enlargement

Last reviewed 01/2018

There are different types of thyroid enlargement (goitres) (1)
  • a simple goitre
    • occurs as a result of enlargement of the thyroid gland in response to insufficient amount of thyroid hormone produced to meet the requirement of the body
    • this usually overcomes mild deficiencies of thyroid hormone (1)
    • a simple goiter may be classified as :
        • an endemic (colloid) goiter
        • sporadic (nontoxic) goiter (1)
  • endemic (colloid) goitres
    • caused by iodine deficiency (1)
      • iodine is essential to the formation of thyroid hormone
    • seen in people living in geographical areas with iodine-depleted soil ( i.e.away from coastal areas), whose diet is deficient in iodine.
  • sporadic (nontoxic) goitres
    • in most cases the cause is unknown (1)
    • occasional cuases include:
      • heredity (2)
      • goitrogens - foods such as cabbage, turnips, brussel sprouts, seaweed, and millet (2)
      • drugs like lithium and aminoglutethimide
    • is usually characterized by normal thyroid function (2)
    • many types are seen (2)
      • diffuse (nontoxic)
        • involving the whole thyroid gland
      • multinodular goitres (nontoxic)(4)
        • are common
        • is characterized by soft nodules that grow slowly
        • often asymptomatic
        • may cause difficulty breathing or swallowing
        • nodules indicates a progression of the goiter
            • 95% are benign
            • 5% are malignant (5)
      • a dominant nodule
        • presence of a dominant nodule needs futher investigation (4)
        • the greatest concern of a solitary nodule is the possibility of carcinoma
        • it is uncommon, majority are benign adenomas or cysts (6)
  • toxic multinodular goitres
    • are caused by the growth of multiple thyroid nodules that produce and secrete excess amounts of thyroid hormone.
    • usually arise from a long-standing simple goite (3)
  • diffuse (toxic)goitres
    • Grave's disease
    • thyroiditis

Reference:

Related pages:

retrosternal goitre