title: Immunotherapy trial as diagnostic test in evaluating patients with presumed autoimmune gastrointestinal dysmotility.
abstract: BACKGROUND
  Chronic gastrointestinal dysmotility greatly impacts the quality of life. Treatment options are limited and generally symptomatic. Neural autoimmunity is an under-recognized etiology. We evaluated immunotherapy as an aid to diagnosing autoimmune gastrointestinal dysmotility (AGID).
  
  
  METHODS
  Twenty-three subjects evaluated at the Mayo Clinic for suspected AGID (August 2006-February 2014) fulfilled the following criteria: (1) prominent symptoms of gastrointestinal dysmotility with abnormalities on scintigraphy-manometry; (2) serological evidence or personal/family history of autoimmune disease; (3) treated by immunotherapy on a trial basis, 6-12 weeks (intravenous immune globulin, 16; or methylprednisolone, 5; or both, 2). Response was defined subjectively (symptomatic improvement) and objectively (gastrointestinal scintigraphy/manometry studies).
  
  
  RESULTS
  Symptoms at presentation: constipation, 18/23; nausea or vomiting, 18/23; weight loss, 17/23; bloating, 13/23; and early satiety, 4/23. Thirteen patients had personal/family history of autoimmunity. Sixteen had neural autoantibodies and 19 had extra-intestinal autonomic testing abnormalities. Cancer was detected in three patients. Preimmunotherapy scintigraphy revealed slowed transit (19/21 evaluated; gastric, 11; small bowel, 12; colonic, 11); manometry studies were abnormal in 7/8. Postimmunotherapy, 17 (74%) had improvement (both symptomatic and scintigraphic, five; symptomatic alone, eight; scintigraphic alone, four). Nine responders re-evaluated had scintigraphic evidence of improvement. The majority of responders who were re-evaluated had improvement in autonomic testing (six of seven) or manometry (two of two).
  
  
  CONCLUSIONS
  This proof of principle study illustrates the importance of considering an autoimmune basis for idiopathic gastrointestinal dysmotility and supports the utility of a diagnostic trial of immunotherapy.
authors.affiliation: Department of Neurology, Mayo Clinic, Rochester, MN, USA.
authors.forename: E P
authors.initials: EP
authors.lastname: Flanagan
authors.forename: Y A
authors.initials: YA
authors.lastname: Saito
authors.forename: V A
authors.initials: VA
authors.lastname: Lennon
authors.forename: A
authors.initials: A
authors.lastname: McKeon
authors.forename: R D
authors.initials: RD
authors.lastname: Fealey
authors.forename: L A
authors.initials: LA
authors.lastname: Szarka
authors.forename: J A
authors.initials: JA
authors.lastname: Murray
authors.forename: A E
authors.initials: AE
authors.lastname: Foxx-Orenstein
authors.forename: J C
authors.initials: JC
authors.lastname: Fox
authors.forename: S J
authors.initials: SJ
authors.lastname: Pittock
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001327:Autoimmune Diseases; D001342:Autonomic Nervous System Diseases / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy*; D005767:Gastrointestinal Diseases / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy* / Q000276:immunology; D005772:Gastrointestinal Transit; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D007167:Immunotherapy; D008297:Male; D008365:Manometry; D008775:Methylprednisolone / Q000627:therapeutic use; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D016756:Immunoglobulins, Intravenous; D008775:Methylprednisolone
keywords: autonomic nervous system; autonomic neuropathy; celiac disease; immunoglobulin; scintigraphy; thyroid disease; transit study