The thing is... no one knows what to expect. Both of my neurologists say it can go three ways.
1. It can slowly resolve and not come back
2. It can come in flares of bad and then a little better but never resolve and continue on like that forever.
3. It can progress.

They watch each case and since this is a relatively new diagnosis, we are all guinea pigs. There are SO many causes and when the cause isn't found, there are only pain meds to manage it. When the cause is found, it is sometimes autoimmune and therefore immunosuppressants would be used. When the cause is toxicity, it can resolve when the toxin is gone or the damage can be irreversible. If the cause is deficiency of vitamins or minerals, it might repair with correcting the deficiency, but again, the nerves might be too damaged. The real answer is that they just don't know what will happen with this. There are also infectious causes which can resolve with the proper antibiotic. It is very frustrating. Sorry.