Gastrointestinal motility disorders represent a heterogeneous group of neuromuscular diseases of the enteric nervous systems. While autoimmune neuromuscular diseases of the central nervous system (CNS) are well described, the role of autoimmunity in enteric nervous system (ENS) has been less studied. Approximately 10% of patients with unexplained gastrointestinal dysmotility diseases have positive serum autoantibodies to peripheral nervous system proteins, suggesting an autoimmune mechanism targeting the enteric nervous system. The investigator's aim is to identify novel anti neuronal antibodies that contribute to autoimmune gastrointestinal motility disorders by analyzing the serum of patients with abnormal gastrointestinal motility.

Autoimmune gastrointestinal dysmotility (AGID) represents a subset of autoimmune disorders that affect the motor function of the gastrointestinal tract. It will often result in refractory gastrointestinal symptoms and poor quality of life. Approximately 10% of patients with unexplained gastrointestinal dysmotility diseases have positive serum autoantibodies to peripheral nervous system gangliosides and glycoproteins, which may be suggestive of an autoimmune mechanism targeting the enteric nervous system. The diagnosis is often made clinically in patients with gastrointestinal dysmotility in the context of primary autoimmune disease or a paraneoplastic syndrome. To date, specific diagnostic tests for AGID disorders do not exist. This study will aim to find whether patients with symptomatic autoimmune gastrointestinal dysmotility (AGID) will have a specific antigen and/or antibody causing the symptoms. The study will also aim to find whether patients with positive autoantibody titers will frequently have positive tilt-table testing (autonomic dysfunction).

The goal of this study is to determine the prevalence of autoimmune antibodies in patients presenting with unexplained GI dysmotility and refractory symptoms, and to examine the outcome (safety, tolerability, and clinical improvement) in a pilot cohort of such patients with a serum screening for antigens, antibodies, and validated questionnaires. This will be a prospective pilot study.

Inclusion Criteria:

• Males and females >13 years old.
• Patient referred to the GI Motility clinic for suspected enteric dysmotility based on chronic refractory gastrointestinal symptoms
• English proficiency and literacy sufficient to sign consent.

Exclusion Criteria:

• Pregnancy documented with a serum or urine pregnancy test. If participants believe that they are pregnant, they will need to notify a study physician who will order a serum or urine test for pregnancy and remove them from the study if the test results come back positive.

Patients with autoimmune gastrointestinal dysmotolity