SLE skin issues?

I have SLE, plus a number of other AIs. One thing I can't get an answer about is this: My shoulders and back, sometimes legs, get little bumps all over them. They look like solid little whiteheads--not squishy. I can scrub them off or rub them off, but they're back the next day. I have NO IDEA what they are. Ideas? Does anyone else have these? They don't itch or hurt, but they're sure persistent.