Influenza A may cause serious neurologic complications, but an autoimmune autonomic
ganglionopathy has rarely been reported. Autoantibodies that impair synaptic transmission
in the autonomic ganglia may cause orthostatic hypotension, gastrointestinal dysmotility,
and sudomotor dysfunction. A 15-year-old girl developed severe and persisting orthostatic
hypotension during influenza A infection. Removal of circulating antibodies by a single
course of intravenous immunoglobulin resulted in rapid and complete recovery.