I have what appears to be black circles on my chest, trunk, and back. I have a fever, extremely tired and weak, swelling in my joints, and hurt everywhere. The black circles are all different sizes, start small and expand and fade away (becoming more purple). The Circles look like this " O ", nothing in the middle or outside, no reddness, no itching, although they do become darker when exposed to light. It's like I have taken a pen and drawn a perfect circle. The doctors are baffled, any ideas?