Charcot–Marie–Tooth disease

Charcot–Marie–Tooth disease
Name	Charcot–Marie–Tooth disease
Specialty	Neurology

Contents

Charcot–Marie–Tooth disease is a hereditary neuropathy characterized by progressive peripheral nerve degeneration affecting distal muscles and sensory function. First described by Jean-Martin Charcot, Pierre Marie, and Howard Henry Tooth in the 19th and early 20th centuries, it is studied across neurology centers such as Mayo Clinic, Johns Hopkins Hospital, and Massachusetts General Hospital and is the subject of patient advocacy by organizations including Muscular Dystrophy Association, CureDuchenne, and Hereditary Neuropathy Foundation. Research into its molecular basis involves institutions like National Institutes of Health, Broad Institute, and Wellcome Trust Sanger Institute with contributions from laboratories at University of Oxford, Harvard University, and Stanford University.

Signs and symptoms

Patients typically present with distal muscle weakness, foot deformities, and sensory loss; clinicians at Cleveland Clinic, Royal College of Physicians, and American Academy of Neurology note common findings such as pes cavus, hammer toes, and gait instability. Examination often reveals distal atrophy and reduced tendon reflexes, prompting referrals to specialists at Great Ormond Street Hospital, UCSF Medical Center, and Toronto General Hospital for multidisciplinary assessment involving orthopedists like those at Mayo Clinic and physiatrists associated with American Academy of Physical Medicine and Rehabilitation. Secondary complications include repetitive strain injuries, falls leading to care at St. Thomas' Hospital, and cosmetic concerns addressed by teams at Johns Hopkins Hospital and Mount Sinai Hospital.

The disorder is genetically heterogeneous, with pathogenic variants identified in genes such as PMP22, MPZ, GJB1, and MFN2; genetic testing panels developed by laboratories at GeneDx, Invitae, and Ambry Genetics are routinely used. Inheritance patterns include autosomal dominant, autosomal recessive, and X-linked transmission, concepts clarified in pedigree analyses taught at Stanford University School of Medicine, University of Cambridge, and Yale School of Medicine. Molecular mechanisms involve demyelination and axonal degeneration mediated by Schwann cell dysfunction, myelin protein abnormalities, and mitochondrial dynamics influenced by proteins studied in research groups at Max Planck Institute for Brain Research, Salk Institute, and Cold Spring Harbor Laboratory. Animal models developed at The Jackson Laboratory, Institut Pasteur, and Karolinska Institutet have demonstrated pathogenic processes such as abnormal nerve conduction, impaired axonal transport, and altered lipid metabolism; these findings inform therapeutic strategies explored in clinical trials registered with U.S. Food and Drug Administration, European Medicines Agency, and ClinicalTrials.gov.

Diagnosis integrates clinical history, neurologic examination, nerve conduction studies performed in electrophysiology labs affiliated with Mayo Clinic, Johns Hopkins Hospital, and Massachusetts General Hospital, and genetic testing provided by GeneDx, Invitae, and 23andMe-linked research programs. Electromyography results and reduced nerve conduction velocities support demyelinating forms while preserved velocities with reduced amplitudes suggest axonal forms, interpretations refined in guidelines from European Academy of Neurology, American Academy of Neurology, and British Peripheral Nerve Society. Differential diagnosis often requires exclusion of metabolic, toxic, and inflammatory neuropathies encountered in referrals to centers such as Cleveland Clinic, UCLA Medical Center, and Mount Sinai Hospital; nerve biopsy, when indicated, is analyzed by neuropathologists trained at Columbia University Irving Medical Center and University College London.

Management is multidisciplinary, combining physical therapy, orthotics, pain management, and surgical correction of deformities delivered by teams at Mayo Clinic, Hospital for Special Surgery, and Great Ormond Street Hospital. Rehabilitation strategies informed by research from World Health Organization collaboratives and clinical programs at Rehabilitation Institute of Chicago emphasize strength training, balance therapy, and gait training. Pharmacologic approaches address neuropathic pain using medications developed and approved by regulatory agencies such as U.S. Food and Drug Administration and European Medicines Agency, while investigational therapies including gene therapy, antisense oligonucleotides, and small-molecule modulators are being evaluated in trials led by Biogen, Novartis, and academic consortia at University of Pennsylvania and University of California, San Diego. Orthopedic interventions, ankle-foot orthoses, and tendon transfers are performed by surgeons affiliated with Johns Hopkins Hospital, Mayo Clinic, and Hospital for Special Surgery; genetic counseling is provided through services at Genetic Alliance, National Society of Genetic Counselors, and university clinics.

Prognosis varies by genotype, phenotype, and comorbidities; longitudinal cohorts studied at National Institutes of Health, University of Oxford, and University of London report variable progression from mild disability to severe impairment necessitating assistive devices, with life expectancy often near normal in many genotypes. Prevalence estimates, compiled by epidemiologists at World Health Organization, Centers for Disease Control and Prevention, and national registries in Denmark, Sweden, and United Kingdom, suggest a global prevalence of approximately 1 in 2,500 individuals, though founder effects reported in populations studied by researchers at University of Toronto, University of Barcelona, and Tel Aviv University produce regional variation. Ongoing natural history studies and registries maintained by Hereditary Neuropathy Foundation, Muscular Dystrophy Association, and academic centers aim to refine genotype–phenotype correlations and inform future therapeutic trials sponsored by entities such as Bill & Melinda Gates Foundation and Wellcome Trust.