Increased radioactive iodine uptake

What it means

An elevated amount of uptake on the radioactive iodine uptake (RAIU) test, which utilizes a radioisotope of iodine to measure how much iodine the thyroid gland absorbs from the blood. The radioactive marker is measured 4-6 hours and in some cases also 24 hours after administration of the radioactive marker.

Rare diseases that can present with this2

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions, and Orphanet separately records 1 disease where this sign is specifically absent. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category