Hi everyone! I just wanted to update you after my appointment with the Neurologist (finally).
The fellow was kind, thorough, intelligent and caring. He was a little old-school, but I liked that and I was happy with his assessment. I am glad for the referral to this particular doctor and I think I really got lucky.
So... drum roll... it turns out he was confident that my signs and symptoms are as a result of an infectious sacral plexus neuritis (probably HSV-1, HSV-2, EBV, or VZV viruses) and NOT fully attributable to FND. The expansion of the pins and needles and pain he believed were functional/hypervigilance, but the original severe weakness and pins and needles in the S1 innervated muscles were as a result of nerve root inflammation.
He looked at my MRI again and pointed out some swelling and reduced CSF flow in the L S1 nerve root as it exited the foramen that had not been picked up previously. This increased my confidence in him and the diagnosis.
He recommended NO further tests as my symptoms are SLOWLY resolving, though was confident that I would achieve 100% recovery as long as I look after my nerves (B12 supplement, limit alcohol, do exercise and reduce anxiety). I just have to follow up with my GP to ensure that the symptoms continue to resolve (if not, more tests will follow to check for the differential dx's).
I am so happy that I can go back to my GP and tell her "see! I told you so!" Having had FND before, I knew my original symptoms were organic this time and I have been vindicated. YAHOO. Never give up when you know your body!