Yes, I think I may have something similar to what you are describing. Except that I don't consider mine a 'rash' per se. At times I do develop a kind of like rash where I'll have half a doz little bumps that look like ant bites, in an uneven circular diagram. When those go away, it leaves a dark color to my skin. It almost looks like the bottom half of my leg and top of middle 3 toes and right above that on top of foot is 'tanned' with freckle looking spots(unevenly and light in color). My DR told me it was from being on my feet too much and it was hundreds of little tiny blood vessels right underneath the skin that were bursting from the pressure (swelling) on my legs/ankles. He had me wear knee high TED hose and it really did seem to help. Since a recent diagnoses of +ANA Lupus if it just might have something to do with that. The Neurologist told me: 'anything's possible'.
My DX's are: High blood pressure, Asthma, genralized Arthritis, IBS, Chronic Insomnia (I guess my sleep patterns were so bad they were off the scale!), Depression/stress/anxiety attacks, yr round seasonal allergies, a swollowing dysphagia (certain foods, ei: bread, fried stuff, and most meats) get stuck in my throat and I can't make it go down and it hurts like a sun of a gun trying to get it to either go up or down (usually I have to make a mad dash to the BR and bring it up!...DR thinks it's part of the depression/stress/anxiety). AND now...just last December I was diagnosed with +ANA Lupus, diagnosed in Jan with Fibromyalgia and just today I received a letter from the Rheumatologist that I tested positive for antiphospholipid syndrome. whatever that is. YEE HAW!!! http://www.healthboards.com/ubb/clown.gif
Back to the subject at hand. What worries me is that this might be some kind of vascular disease (antiphospholipid syndrome) and that is what the redness on bottom of legs is from. From lack of circulation. I go back to the Rheumatologist on the 28th and am going to ask him about the redness in my legs. Mine havn't bothered me for about a yr and just a few weeks ago, started acting up again. They are beat red (sunburned looking) all away around my leg from the bottom of my calf to the top of my foot, clear down to my toes. It looks like I just poured steaming hot water on my legs! I dont know whether to put on the TED hose or wait and see what the RA DR. says.
Keep in touch about your legs and let me know how they are progessing and if you've been to the DR., what he says. take care and be safe!