No matter, I think the treatment for all auto-immune skin diseases is steroids in hopes of putting the horse in remission and/or finding he lowest dose possible to keep the disease from returning.
I was the one of the people that mentioned Pemphigus Foliaceus because it is one of the more common equine auto-immune diseases that affects skin. There is a Yahoo group you can join (for free) and look at photos of other horses that have it and are now in remission. Some of the members there are quite educated in the disease and may be able to answer any questions you might have.
This disease presents differently in horses. Some only lose hair, some have sores, some have scabs, some itch, some swell, some have fever, ect. etc. Often the disease occurs at one particular time of year, regresses, and then appears again the following year or when the horse has been stressed or something sets it off.
But yes, steroid-induced laminitis is the big concern with treatment.