Jones, Lyell K.

ABSTRACTIntroduction: Valosin containing protein (VCP) mutations cause a rare disorder characterized by hereditary inclusion body myopathy, Paget disease of bone (PDB), and frontotemporal dementia (FTD) with variable penetrance. VCP mutations have also been linked to amyotrophic lateral sclerosis and Charcot‐Marie‐Tooth disease type 2. Methods: Review of clinical, serological, electrophysiological, and myopathological findings of 6 VCP‐opathy patients from 4 unrelated families. Results: Patients manifested muscle weakness between ages 40 and 53 years and developed predominant asymmetric limb girdle weakness. One patient had distal weakness at onset and co‐existing peripheral neuropathy. Another patient had PDB, 1 had mild cognitive deficits, and 1 had FTD. All patients had myopathic and neurogenic electromyographic findings with predominant neurogenic changes in 2. Rimmed vacuoles were infrequent, while neurogenic changes were prominent in muscle biopsies. Conclusions: VCP‐opathy is a multifaceted disorder in which myopathy and peripheral neuropathy can coexist. The electrophysiological and pathological neurogenic changes raise the possibility of coexisting motor neuron involvement. Muscle Nerve, 2015 Muscle Nerve 54: 94–99, 2016 Muscle Nerve 54: 94–99, 2016