Syphilis showing 5 months after...very much doubt that and from a 19 year old American girl...highly doubt that one also. I would not be worried about syphilis.
I thoguht it was a long shot, her having it in the first place, and then not developing symptoms until this late. Plus from what I've read the antibiotics I've been on seem to be very similar to the ones prescribed for syphilis treatment.
The spot appears to be healing.
What could have caused it besides syphilis?
Things like that can be caused from so many different things...irritation, fungial, bacterial...can't really say.
I appreciate the help. It doesn't seem to resemble any of the pictures of syphilis chancres, and I seem to remember having this happen before.