--you want a specialty facility.

These include:

The Cornell Weill Center for Peripheral Neuropathy (New York)
Massachusetts General Hospital neurology (Boston)
The Jack Miller Center (Chicago)
Washington University Medical Center, Neuromuscular Division (St. Louis)
The University of San Francisco Medical Center (San Francisco)
Johns Hopkins Medical Center (Baltimore)

There are probably others that would provide comprehensive testing and treatment approaches; these are the ones that have been research hotbeds into the condition over the years.