Misdiagnosis and diagnostic pitfalls of chronic inflammatory demyelinating polyradiculoneuropathy.

Over- and underdiagnosis of CIDP is common. Diagnostic pitfalls include lack of attention to proximal muscle weakness as a diagnostic hallmark of CIDP, insufficient recognition of clinical atypical phenotypes, overreliance on CSF protein levels, misinterpretation of nerve conduction studies and poor adherence to electrodiagnostic criteria, and failure to exclude other causes of polyneuropathy.