What early clinical findings help in differentiating CIDP vs. POEMS?

I would like to share that I had a very challenging experience last year with a patient ultimately diagnosed with POEMS by myself, after more than one year of treatment as CIDP. There were multiple reasons it was challenging:

1.) The patient presented initially with NO systemic features - just the neuropathy, which was clearly demyelinating, associated with proximal + distal weakness, and at least one nerve showed clear motor conduction block.

2.) He initially showed a partial objective positive response to steroids + IVIG.

3.) He did have an IgA lambda monoclonal protein upfront, but VEGF levels were normal before treatment, and remained normal 6 months later. They only became slightly abnormal at 12 months (a couple of hundreds, not thousand...

Aside from the factum manifestum of the clinical/laboratory manifestations of “POEMS” which differentiate CIDP from POEMS, the electrophysiologic differentiators were well delineated by Mauermann et al., PMID 22396441. This study establishes that EDx studies must supplement a purely clinical examination.

The information-dense abstract follows:

Objective: POEMS syndrome (the acronym reflects the common features: Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal protein and Skin changes) is a paraneoplastic disorder with a 'demyelinating' peripheral neuropathy that is often mistaken for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). The nerve conduction study (NCS) and electromyography (EMG) attributes that might diffe...