Charcot-Marie-Tooth (CMT) disease consists of a group of disorders with progressive nerve degeneration causing difficulties in movement and sensation. Many types caused by gene mutations have been described, often with overlapping symptoms and signs, and in some there is associated damage to the optic nerve. Early-onset (congenital and juvenile) glaucoma can also be present.
Symptoms of weakness, particularly in the arms and legs, often have their onset in late childhood or early adulthood. The disease is relentlessly progressive and often the size of muscles decreases (atrophy). The feet are frequently deformed (pes cavus with hammer toes). Changes in sensation and sometimes numbness are common. Diagnostic tests such the ability of nerves to carry signals (nerve conduction) can be helpful. Mental impairment is uncommon. A few patients suffer hearing loss.
More than 40 gene mutations have been identified in Charcot-Marie-Tooth disease. Inheritance patterns include autosomal dominant, autosomal recessive, X-linked dominant, and X-linked recessive. Due to the overlapping signs and symptoms among the various types of CMT and the variable degrees of severity, gene testing may be the only way to determine which specific condition is present. It may also be necessary to determine the risk of recurrence among subsequent generations.
A neurologist should be consulted to determine the diagnosis. Management requires a multidisciplinary team of neurologists, orthopedic surgeons, physical and vocational therapists, pain specialists, and audiologists. The foot deformities can be minimized with surgery and certain medications help with the nerve pain. Ophthalmologists should be consulted to rule out or treat glaucoma.
Many individuals have only mild disease and lead nearly normal lives. Most patients have some degree of disability (walking, manipulating objects, etc.) but longevity is generally not impacted.