Screening for amphiphysin antibodies is used in the investigation of patients with suspected paraneoplastic syndrome (particularly Stiff's syndrome) and autoimmune encephalitis.
Antibodies against amphiphysin occur in patients with the paraneoplastic version of Stiff's syndrome but may also be observed in autoimmune encephalitis. Antibodies against amphiphysin are associated with breast cancer and small cell lung cancer. Neurological symptoms can precede the diagnosis of cancer up to five years earlier.
See also: Anti-Neural Antibodies