What Could Cause Red Skin Eruptions That Turn Into Itchy ,crusty Sores?

I have a condition that starts with small red skin eruptions like a blster/burn. Over a few days the serous material becomes crusty and the sores form. They burn and itch like chicken pox, they are pitted and painful. After the skin outbreak I get a sore throat and all my joints hurt severally. My lymph nodes get swollen. I have been tested for arthritis, SLE Lyme disease, Gout. I had 3 out of 6 elevated numbers on lyme test, but was told it was not Lyme disease All other tests are negative. My sed rates are normal. I also have hematuria which has neve been resolved. The only thing that seems to help is prednisone, At times I also get sores in my mouth also, like canker sores. the only thing that I have been diagnosed with is Epstein-Barr, chronic fatique and fibromyalgia. My mother had arthritis ad my father had gout. I don't have shingles.
I had chicken pox ,Rubella and mumps as a child. I hope you can help me