9 year old has numbness in left leg

My 9 year old daughter has had almost constant numbness in her left leg since Jan.Sometimes her left arm too.She has mitral valve prolapse,wolfe parkinson white syndrome and PANDAS.For over a month her cbc came back with a white count of 1,000.Her cardioligist says the numbness is not heart related and her neurologist says its not neurolgical.She has had an mri,eeg and ct scan of the brain.She had had every blood test available,lyme,b12,lead,lupus,ra etc.
She is fit and active and very happy & well rounded.But the misery she has with the numbness gets worse every single day.I am running out of questions and no one has any answers or help.
Please,do you have any ideas?Thanks

[PaulMD]

Hi.  I'm sorry to learn that your daughter has been experiencing all of these in such as young age.  If all the tests have been already done, then it will seem be very hard to diagnose the situation.  One more test that I think may give us answers (though may cause some discomfort and pain) would be a nerve biopsy.  This should tell us if we are dealing with a primary neuropathic problem or not.  However, this should be discussed well with her doctors since this would entail a biopsy procedure that can be uncomfortable and painful.  Regards.