Charcot-Marie-Tooth disease (hereditary)Definition Charcot-Marie-Tooth disease defines a group of inherited, slowly progressive disorders that result from progressive damage to nerves. Symptoms include numbness and wasting of muscle tissue, first in the feet and legs, then in the hands and arms. Causes, incidence, and risk factors Charcot-Marie-Tooth diseases involve damage to nerves (neuropathy), usually from loss of the electrical insulation (myelin ) around nerve fibers. All nerves are affected, but motor nerves (the nerves that stimulate movement) are most severely affected. The nerves in the legs are affected first and most severely. Symptoms usually begin between mid-childhood and early adulthood. The disorder is inherited, with autosomal dominant, autosomal recessive as well as X-linked recessive inheritance patterns. At least 4 genes have been discovered to be the cause of this group of diseases. Charcot-Marie-Tooth disease causes destruction of the myelin sheath in some people. In other people, the central (axon) portion of the nerve cell degenerates. The disorder most commonly affects the nerves to the feet and legs, most significantly the peroneal nerve. The damage is slowly progressive, usually beginning with foot drop and progressing up the legs. There is a loss of muscle control and muscle tone, and eventual loss of muscle mass caused by lack of nervous stimulation to the muscles. Symptoms
Signs and tests An examination by touch may reveal thickened nerve bundles under the skin of the legs in the demyelinating form of Charcot-Marie-Tooth disease. The stretch reflexes in the legs are absent. There is loss of muscle control and atrophy in the foot or leg. There is difficulty with lifting up the foot (dorsiflexion) and with toe-out movements (eversion).
Treatment There is no known cure for Charcot-Marie-Tooth disease. Treatment is aimed at maximizing independence. Orthopedic surgery or equipment (such as braces or orthopedic shoes) may make it easier to walk. Vocational counseling, occupational therapy, or physical therapy may be appropriate for some people to help maintain muscle strength and maximize independent functioning. Expectations (prognosis) Charcot-Marie-Tooth disease is slowly progressive, eventually causing disability. It is not life-threatening. It is not usually painful, but there may be numbness in the area. Complications
Calling your health care provider Call for an appointment with your health care provider if there is persistent weakness or decreased sensation in the feet or legs. Prevention Genetic counseling and testing is advised if there is a strong family history of the disorder. Illustrations
Page Content: Progressive neuropathic (peroneal) muscular atrophy; Hereditary peroneal nerve dysfunction; Neuropathy - peroneal (hereditary); Hereditary motor and sensory neuropathy ; hereditary motor and sensory neuropathy |