Case report of a woman with anti amphiphysin positive stiff person syndrome.

Stiff person syndrome is a rare neuroimmunological disease, characterized by severe, involuntary stiffness with superimposed painful muscle spasms, which are worsened by external stimuli. The classical form is associated with high levels of antibodies against glutamic acid decarboxylase. One of the variant forms is associated with antibodies against amphiphysin. This entity is a paraneoplastic syndrome, caused primarily by breast cancer, secondarily by lung cancer. Symptomatic therapy of anti amphiphysin positive stiff person syndrome includes treatment with benzodiazepines and baclofen (including intrathecal baclofen therapy). The effect of immunological therapies is controversial. Treatment of the underlying cancer may be very effective. In this report, we describe a 68 year old female presenting with an unusally rapidly developing anti amphiphysin positive stiff person syndrome, which was associated with breast cancer. Her painful spasms abolished after intrathecal baclofen treatment was initiated. Her condition improved spontaneously and significantly after cancer treatment, which enabled to start her complex rehabilitation and the simultaneous dose reduction of the intrathecal baclofen. The bedridden patient improved to using a rollator walker and the baclofen pump could be removed 18 monthes after breast surgery. This highlights the importance of cancer screening and treatment in anti amphiphysin positive stiff person syndrome cases.