| Type 1 | Type 2 | |
|---|---|---|
pre-existing thyroid disease |
Yes | No |
Ultrasound pattern |
diffuse or nodular gointer | heterogeneous |
Doppler sonography |
normal or increased flow | decreased flow |
24h radioiodine uptake |
normal or elevated (typically >5%/24h) | very low (typically <2%/24h) |
thyroid autoantibodies |
may be present | usually absent |
response to steroids |
No | Usually Yes |
From Conen, et al, JACC Vol 49, No. 24, 2007 June 19, 2350-5