title: Rapidly progressive asymmetrical weakness in Charcot-Marie-Tooth disease type 4J resembles chronic inflammatory demyelinating polyneuropathy.
abstract: Charcot-Marie-Tooth disease type 4J (CMT4J), a rare form of demyelinating CMT, caused by recessive mutations in the phosphoinositide phosphatase FIG4 gene, is characterised by progressive proximal and distal weakness and evidence of chronic denervation in both proximal and distal muscles. We describe a patient with a previous diagnosis of CMT1 who presented with a two year history of rapidly progressive weakness in a single limb, resembling an acquired inflammatory neuropathy. Nerve conduction studies showed an asymmetrical demyelinating neuropathy with conduction block and temporal dispersion. FIG4 sequencing identified a compound heterozygous I41T/K278YfsX5 genotype. CMT4J secondary to FIG4 mutations should be added to the list of inherited neuropathies that need to be considered in suspected cases of inflammatory demyelinating neuropathy, especially if there is a background history of a more slowly progressive neuropathy.
authors.affiliation: MRC Centre for Neuromuscular Diseases, Department of Molecular Neurosciences, National Hospital for Neurology and Neurosurgery, UCL Institute of Neurology, London, UK.
authors.forename: Ellen
authors.initials: E
authors.lastname: Cottenie
authors.forename: Manoj P
authors.initials: MP
authors.lastname: Menezes
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Rossor
authors.forename: Jasper M
authors.initials: JM
authors.lastname: Morrow
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Yousry
authors.forename: David J
authors.initials: DJ
authors.lastname: Dick
authors.forename: Janice R
authors.initials: JR
authors.lastname: Anderson
authors.forename: Zane
authors.initials: Z
authors.lastname: Jaunmuktane
authors.forename: Sebastian
authors.initials: S
authors.lastname: Brandner
authors.forename: Julian C
authors.initials: JC
authors.lastname: Blake
authors.forename: Henry
authors.initials: H
authors.lastname: Houlden
authors.forename: Mary M
authors.initials: MM
authors.lastname: Reilly
mesh_terms: D000328:Adult; D001369:Axons / Q000648:ultrastructure; D002607:Charcot-Marie-Tooth Disease / Q000175:diagnosis / Q000235:genetics*; D003937:Diagnosis, Differential; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D009154:Mutation / Q000235:genetics*; D020277:Polyradiculoneuropathy, Chronic Inflammatory Demyelinating / Q000235:genetics*