title: Hereditary neuropathy with liability to pressure palsies in childhood: Case series and literature update.
abstract: Hereditary Neuropathy with Liability to Pressure Palsy (HNPP) is a rare condition in childhood with a diverse range of clinical presentations. We analyzed the clinical presentation and electrophysiological data of 12 children with a confirmed PMP22 gene deletion and reviewed the published reports of HNPP in children and compared our data with the reports from the literature review. Peroneal palsy was the most common presentation (42%) followed by brachial plexus palsy in 25% of our cases. Nerve conduction studies were always suggestive of the diagnosis demonstrating 3 major patterns: multifocal demyelination at the area of entrapment, generalized sensory-motor polyneuropathy and a combination of the two first patterns in a vast majority (60%). Surprisingly, there was bilateral or unilateral electrophysiological entrapment of the median nerve at the carpal tunnel in all our patients. The clinical presentation of HNPP in childhood is heterogeneous and electrophysiological findings are helpful in establishing the diagnosis. Any unexplained mononeuropathy or multifocal neuropathy should lead to PMP22 gene testing to look for the deletion. Early diagnosis is important in order to facilitate appropriate genetic counseling and also for the appropriate care for these patients.
authors.affiliation: The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada. Electronic address: nicolas.chrestian@sickkids.ca.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Chrestian
authors.affiliation: Children's Hospital of Eastern Ontario, University of Ottawa, 401 Smyth Road, Ottawa, Ontario K1H 8L1, Canada.
authors.forename: Hugh
authors.initials: H
authors.lastname: McMillan
authors.affiliation: The Montreal Children's Hospital, McGill University, 1001 Boulevard Décarie, Montreal, Quebec H4A 3J1, Canada.
authors.forename: Chantal
authors.initials: C
authors.lastname: Poulin
authors.affiliation: Children's Health Research Institute Western University, 800 Commissioners Road East, London, Ontario N6C 2V5, Canada.
authors.forename: Craig
authors.initials: C
authors.lastname: Campbell
authors.affiliation: The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
authors.forename: Jiri
authors.initials: J
authors.lastname: Vajsar
mesh_terms: D000293:Adolescent; D001176:Arthrogryposis / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D017353:Gene Deletion; D015417:Hereditary Sensory and Motor Neuropathy / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D006801:Humans; D008297:Male; D009185:Myelin Proteins / Q000235:genetics; D009431:Neural Conduction
chemical_list: D009185:Myelin Proteins; C073687:PMP22 protein, human
keywords: Childhood; HNPP; Hereditary; Mononeuropathies; PMP22 protein