Guillain-Barré Syndrome Presenting as Symmetrical Proximal Muscle Weakness: An Atypical Presentation.

Guillain-Barré syndrome occurs via molecular mimicry when a trigger sets off an immune response on peripheral nerve epitopes. Patients typically report an antecedent infection, such as an upper respiratory infection or Campylobacter jejuni gastroenteritis. It is typically characterized by progressive, symmetric muscle weakness with absent/decreased deep tendon reflexes. Most cases in the literature report that the paralysis begins in the legs distally and ascends to the extremities. Patients may have sensory symptoms or dysautonomia as well. Notable variant forms include acute motor axonal neuropathy, acute motor/sensory neuropathy, Miller Fisher syndrome, and Bickerstaff brainstem encephalitis. Diagnosis is confirmed if a lumbar puncture shows albuminocytologic dissociation (typically 45 to 200 mg/dL). Nerve conduction studies may also be considered but are not necessary. Management is largely supportive, but intravenous immunoglobulin and/or plasmapheresis for more severe cases may be considered.