Why is my big toenail dark blue from the cuticle up? about 6 weeks ago, my toenail started getting a dark-blue spot. my sister, who is a nurse, told me it might be raynaud's syndrome, a bruise, or a sign that my toenail is regrowing itself a replacement.

First : First of all, let me thank you for posting pictures! it will make any answer given here more accurate and informative. Given the well-defined margins in the picture, it's unlikely melanoma. But... Since the incidence of melanoma has skyrocketed, out pacing any other form of cancer, and given that melanoma is a particularly deadly cancer, the safest advice i can give you is to have the nail bed biopsied. It's no big deal to do this, and won't keep you off your feet, and you'll rest easy knowing you're ok. In my 32 years of practice, I have seen melanoma in the foot only twice, but in each time, it was under the big toenail. Also, a nice benefit from having your nail bed biopsied is the toenail needs to be removed in order to do it. If it's just a collection of blood under there, removing the toenail will clear it, and you will re-grow another nail that will look just as lovely as your nail used to look before this black thing showed up. A podiatrist or dermatologist can do the biopsy. Please have this done. Good luck!

Need exam: A dark blue spot under a nail can be trauma related, or a tumor under the nail and even a melanoma skin cancer can appear as such. Suggest asap exam with a physician .