Hi juniemarie if you can, could you provide more information on what medications and suppliments your on, are you taking anything that contains Selenium, or copper, or foods like brazil nuts that contain high amounts of these things. is there any chance you've had any enviromental exposure to metals, have you had your kidneys checked recently or got any other strange symptoms. If you can provide this information i'll see if i can look up what's causing it for you.
all the best