I'm sorry I havn't gotten back to you sooner....
I have CIDP an auto-immune form of peripheral neuropathy as well. Tho I'm not Anti-Mag. We have 'relative' conditions.

Here are a few web sites that should help you understand things.
This discusses how doctors should test progressively about neuropathies"
http://www.aafp.org/afp/980215ap/poncelet.html

This is technical, but you will find that there are so many different 'immune' neuropathies that even neuro's well versed in this area can't possibly know them all:
http://neuromuscular.wustl.edu/antib...imdem.html#mag
Also a list of diagnostic testing:
http://neuromuscular.wustl.edu/lab/nvworkup.htm#lab

Lastly a web site put together by some folks on the PN forums here can help you keep track of the tests you have, and maybe should have:
http://www.lizajane.org/

The Peripheral Neuropathy forums are here:
http://neurotalk.psychcentral.com/forum20.html
At the top of the forum are things called 'Important links/stickies' Take a look at many of the sites referenced there, they may help.

One thing I think you MUST get is a copy of your medical records from Iowa!
It may cost you a fee, but that you had been receiving IVIG and are not now is bothersome. I know as I receive it monthly and have for 4 years. Your new neuro must see these records [a copy only! Keep those originals for the future]. IF he shows no interest in really treating you, well, it's time to get another opinion! It took me a year and 3 neuros to get my diagnosis, so please keep at it!

Don't hesitate to ask questions! There are lots of very good and helpful folks here! 's - j