perchlorate discharge test

Last reviewed 01/2018

This is a test to confirm a clinical diagnosis of Pendred's syndrome.

Perchlorate displaces non-organified iodide from the thyroid. In Pendred's syndrome there is a defect in the organification of iodine.

The basis of the perchlorate discharge test is:

  • radioactive iodine is given to the patient
  • time is allowed for the iodine to be captured by the thyroid
  • oral perchlorate is administered
  • patients with Pendred's syndrome show an abnormally rapid loss of radioactive iodine from the thyroid