Dear onecent,
it sounds like you may have a problem with candida overgrowth. That would help explain the carbo problem. Also I have read (don't ask me exactly where, somewhere on the 'net') that candida can be the cause of arthritis.
In 1994, I was a cripple from Arthritis and found a book that told about certain foods that were in the nightshade family, potatoes, peppers, tomatoes, eggplant and tobacco, causing Arthritis by the poison contained in the foods attacking the joint membrains and causing them to deterate. Leaving off these foods for 6 weeks produced a miracle in me.
Also I discovered some time later a substance available at health food stores called cetyl myristoleate that helps with all auto-immune deseases, especia;ly arthritis.