- Thyrotoxicosis implies symptomatic excess thyroid hormone, without referring to an etiology
- Hyperthyroidism implies excess intra-thyroidal production of hormone
- Causes for thyrotoxicosis can be divided into 1) Disorders associated with normal or high radioiodine uptake or 2) Disorders associated with low or absence radioiodine uptake
2) Normal or High radioiodine uptake
- Graves disease
- Toxic multinodular goiter
- Toxic adenoma
- Iodine induced hyperthyroidism: i.e. CT contrast or amiodarone (iodine uptake may be low in this case if exogenous iodine has a long half-life or continues to be given, as it will dilute the radioactive tracer)
- Trophoblastic disease/germ cell tumours: mediated by beta-HCG which cross reacts with TSH receptors. Examples include: hydatidiform moles/choriocarcinoma in females and testicular germ cell tumours.
- Secondary hyperthyroidism from a functioning pituitary adenoma
3) Low or absent radioiodine uptake
- Thyroiditis:
- Pyogenic thyroiditis
- Viral thyroiditis
- Hashimoto's thyroiditis
- Postpartum thyroiditis (a form of Hashimoto's occuring postpartum)
- Radiation thyroiditis
- Palpation thyroiditis (after a surgical excision on the thyroid from it vascular bed)
- Drug induced: amiodarone, lithium
No comments :
Post a Comment