FIG4 and polyneuropathy: For example, it has been previously described that the pathophysiology of CMT 4J resembles that of acquired polyneuropathies (Hu et al., 2018), and that some patients with pathogenic variants in FIG4 have been initially misdiagnosed as CIDP (due to clinical, electrophysiological, and imaging features common in both CIDP and CMT 4J, such as asymmetric involvement, conduction blocks, and temporal dispersion).