help! please suggest possible diagnosis

[metel]

helllo,
my sister has been having on and off pain and weakness in her left arm and leg. it started about a year ago with her thumb where she said she feels numbness. we disregarded it and thought it might not be something serious. however, it progressed to her left arm and leg. these have less strength than the other side and my sister feels intermittent pain. she is also having frequent headaches.we also noticed that her left arm and leg has started to decrease in muscle mass. last october 2007, she had an attack where her left arm and leg has been temporarily paralyzed. she could not feel anything and can't move them. she was brought to the hospital where a cranial CT scan was done but showed normal results. she was given aspirin and phenobarbital. cranial MRI, 2Decho, ANA determination and all routine lab tests were done and they all showed normal results. her neurologist doesn't know what was wrong with her. at first she ruled out stroke in the young but no lab results/tests supported this. my sister was subsequently discharged. no follow up was done. from the time she was discharged until now, she experienced the same symptoms. headaches, weakness in the left extremities as compared to the other side, intermittent pain and numbness. what concerns me the most is the very noticable atrophy of her left extremities. can you please help us determine the diagnosis of my sister? thank you so much.

[Dr_prakesh]

The most important thing to know is what her neurological examination shows...when was the last time she was examined....please post the full transcript of the neurological examination.

Was an EMG / Nerve conduction study done?