Neuropathology and binding studies in anti-amphiphysin-associated stiff-person syndrome.

The authors report a 71-year-old woman with amphiphysin-associated paraneoplastic stiff-person syndrome, opsoclonus, and encephalopathy. The patient's symptoms temporarily responded to plasmapheresis in parallel with a decline of serum anti-amphiphysin antibody titers. Later, the encephalopathy progressed rapidly and the patient died. Binding studies and the detection of autoantibodies in the patient's CNS as well as the treatment response suggest a pathogenic role of the anti-amphiphysin antibodies.