My 15 yr old son is very medically complex with a multitude of rare diagnoses including Eosinophilic Esophagitis, Adrenal Insufficiency and severe Dysmotility/Chronic Intestinal Pseudo Obstruction. About a year ago he was diagnosed with a rare type of Dysautonomia call Autoimmune Autonomic Ganglionpathy, POTS and small fiber neuropathy. He is seronegative for the ACHR antibody but positive for paraneoplastic and striated muscle antibodies. He is very symptomatic. He was also found to have a 6cm benign bone tumor growing on his upper arm. He is HLA B27 positive as well. We tried treating his Autoimmune disease aggressively with high dose steroid infusions and IVIG but he did not respond and could not tolerate them either, so his doctors do not feel Rituxan or Plasmapheresis will work for him now. Soon he will go in for a PET scan to see if he does have any tumors they have not found yet causing these antibodies to produce. What could be the reasons he is producing the striated muscle antibody and what will happen if left untreated? Will these antibodies start to attack his organs?? He is progressively getting worse and his quality of life is very poor.