12 year old son with atypical GBS/CIDP

FYI this is also posted to the CIP/child forum -wasn’t sure where I would get the best response

Hi- I am writing from my 12 year old son’s hospital room at Seattle Children’s Hospital. After many weeks (7 weeks until diagnosis) he has been diagnosed with GBS that has been changed to “sub acute”. Because his timeline and progression of symptoms are not typical of GBS the word Chronic has been thrown into the pot also, although no one seems ready to make that leap yet. We have had 2 doses of IVIG and after progressing weakness we are now about to complete our 5th time of a 5 treatment plan of Plasmapheresis. The only change he has noticed is a “jumping of his nerves” like if a door closes or a loud noise happens he is not startled but his nerves are. We are hoping this may be a good sign?? The Dr’s don’t seem to know or won’t say.
Chad’s symptoms started in Mid March with pain in the back of his thighs and calves which led to him not being able to bend over or extend his legs out when sitting. The pain didn’t stop him he just couldn’t do it. A couple of weeks in the pain and lack of extension went into his biceps and he couldn’t reach over his head. He was admitted here for an MRI and testing around week 3 and they said “Not neurological maybe viral go back to Physical therapy” Then 10 days after that he had a follow up at our PCP’s insistence (He had told them he suspected GBS) where once again they said not neurological…how is school and your friendships?? We all know what that means…
Finally around week seven he was unable to climb stairs, rise from the floor or up onto his toes, jogging was impossible and walking was getting more difficult. I had finally gotten him into Rheumatology with a weak ANA result, since I felt it might be Juvenile Polymyositis or Dermatomyositis, but prior to our 3 o’clock appointment our PCP once again INSISTED neurology take another look. This time they admitted him for a NCS which showed to everyones surprise slowing nerves. He had his 2 dose treatment of IVIG and was admitted to Rehab. During his week there I never felt he was getting better only worse and although I told them he wasn’t supporting himself at all they felt with their muscle testing that his weakness had stabilized and we could go home. We did…for 3 days and after I went back to my PCP and begged for an MRI with contrast of his legs to see if there was possibly an overlapping muscle condition, we were readmitted and the plan changed to Plasmapheresis…so here we sit. They say definitely no muscle involvement but they seemed so focused on the pain as the reason he cannot stand or walk. He can’t roll over unassisted, touch the top of his head or even push a button on his TV remote anymore without Herculean effort. He says it is not the pain his body is so weak he can’t do it.
Does this story sound familiar to any other parent with this syndrome? I am coming to terms with the fact that his case and timeline lend themselves more to CIDP but since the Dr’s won’t say we have no idea what to expect…should he at least see some recovery before he relapses? How long can it take to see results after plasmapheresis? I know the nerves have to regenerate but should we see ANY evidence that this process has at least stopped (or gone into a temporary remission)?
Sorry this is so long but we are desperate for answers, help or advice…Any ideas??
Thank you!