May 9, 2014
Siemens has informed the
Clinical Laboratory that samples containing fluorescein dye can produce falsely
depressed TSH values. With fluorescein intereference TSH can be as low as
<0.01 mlU/L. Evidence suggests that patients undergoing fluorescein
dye angiography can retain small amounts of fluorescein for up to 48 to 72
hours post-treatment. In the cases of patients with renal insufficiency,
retention could be much longer.