Snapshot A 35-year-old man presents to the emergency department for difficulty with walking. His symptoms began approximately 1 week ago and has progressively worsened. He has noticed some lightheadedness with standing up from a seated position and some numbness in the bilateral lower extremities. Physical examination is notable for 4/5 power and decreased sensation to light touch and pinprick in the bilateral lower extremity and absent patellar and ankle reflexes. A lumbar puncture is performed, which demonstrates a cell count of 1/uL, protein is 135 mg/dL, and glucose is 65 mg/dL. He is admitted to the neurology floor for frequent negative inspiratory pressure and vital capacity measures and intravenous immunoglobulin. Introduction Definition login to view 7 more bullets Epidemiology Risk factors login to view 7 more bullets Pathogenesis A previous infection triggers an immune response that cross-reacts with parts of the peripheral nerve via molecular mimicry login to view 1 more bullet Presentation Symptoms/physical exam login to view 10 more bullets Imaging MRI login to view 6 more bullets Studies Spirometry login to view 2 more bullets Lumbar puncture login to view 3 more bullets Nerve conduction studies login to view 2 more bullets Differential Acute myelopathy login to view 2 more bullets Treatment Conservative login to view 9 more bullets Medical login to view 7 more bullets Complications Respiratory failure Autonomic instability Complications from IVIG and plasmapheresis Prognosis Improved outcomes with either plasmapheresis or intravenous immunoglobulin