Re: Beaus lines
Yeah, I've had em for years. They'll show up anytime that you're ill enough to disrupt the nail growth. You'll find them after a case of the flu or any other serious illness, especially if a fever's involved. A lot of people also notice a major hair shed about 2 to 3 months after they've been sick due to the same type of process where the keratin doesn't get laid down proper.
They can be due to thyroid issues. Hypers often have a lifting of the nail at the top of the bed too to go along with the lines. Psoriasis of the nails can cause both of them too. Fingernails are a very good reflection into the body but they cannot pinpoint the what in most instances. They just give you a clue that you need to look harder.
I hope you get to the bottom of your issues. I know how hard it is to deal with but persistence often pays off. Good luck.