How do you evaluate a patient with MGUS and peripheral neuropathy?

When I see a patient with MGUS and peripheral neuropathy, I think about it in stages:

1. Does the patient have an IgM-monoclonal gammopathy? If so, then I think about DADS-M. An EMG/NCS, anti-MAG antibody, PET scan, and bone marrow biopsy are generally all part of the workup. I try to do MYD88 testing...