Charcot-Marie-Tooth type 2 and distal hereditary motor neuropathy: Clinical, neurophysiological and genetic findings from a single-centre experience

OBJECTIVES: CMT is a group of heterogeneous motor and sensory neuropathies divided into demyelinating (CMT1) and axonal forms (CMT2). Distal Hereditary Motor Neuropathy (dHMN) is a motor neuropathy/neuronopathy which resembles CMT. Final genetic diagnosis is poor in CMT2 and in dHMN when compared with CMT1. Our aim is to report clinical, neurophysiological and genetic findings in a cohort of patients with axonal inherited neuropathies. PATIENTS AND METHODS: We report clinical, neurophysiological and genetic findings from 45 patients with CMT2 or dHMN, coming from 39 unrelated families, observed in our Institute of Neurology over a 20-year period. RESULTS: Clinical and electrophysiological examinations showed that 38 patients had CMT2 and 7 patients presented dHMN. Extensive genetic evaluation showed 6 mutations in MFN2, 4 mutations in HSPB1, 2 mutations in BSCL2, 3 mutations in GJB1, 1 mutation in MPZ. CONCLUSION: Since next-generation sequencing will not be easily accessible, epidemiological data and clinical "phenotyping" remain the best strategy for clinicians to reach a correct genetic diagnosis in CMT2 and dHMN patients.