Hi My Daughter Who Is 18 Years Old Developable Rash

Hi my daughter who is 18 years old developable rash that started on her face and migrated down to her arms, stomach and legs. This rash came on suddenly and has not gone away since April. She has been seen by her pediatrician, a dermatologist and by a general medicine doctor. She has been complaining of fatigue and joint pain. The general doctor tested her for several things and the only thing she said she tested positive for was Sjogren's. Is the rash a characteristic of it?