harlequin's syndrome associated with lupus?

I have lupus, and my 27 year old daughter has been diagnosed with LLS, lupus-like syndrome, which has been explained to us as having virtually the same symptoms as lupus, but less serious.  She has a very strange reaction to exercise--half her face will flush and turn red and sweat profusely, but the other half will remain dry and cool.  The dividing line goes exactly down the center of her face, with sweat dripping down one side of her nose.  Our lupus doctor has said that he thinks it is a type of nerve damage and doesn't seem to worry about it.  What exactly would cause this?  Will any further damage likely occur?  (I read in a popular advice column the description of the same thing, and it was called harlequin's syndrome).  Thank you for any enlightenment on this puzzling question.

[CCF Neuro[P] MD, RPS]

Dear Nell:

Sorry to hear about your daughter.  The first thing that I think of is a central canal (called a syrinx) within the brainstem and/or cervical cord.  We have seen this mimic a harlequin-like event.  I have read that this can be seen in lupus as part of a vasculitis, but I haven't seen it myself.  I would recommend getting a MRI of the brainstem and cervical cord.  If this is indeed the case, there is not much to do, but at least the indictation of lupus would be reduced and likely not at all for this symptom.

Sincerely,

CCF Neuro MD