Charcot-Marie-Tooth Disease (CMT) Symptom
Peripheral neuropathy is damage to the peripheral nerves and results in a tingling, painful, or burning sensation in the extremities. It most commonly occurs in the legs. Other symptoms of peripheral neuropathy can include weakness and numbness.
*Charcot-Marie-Tooth disease (CMT) facts
*Charcot-Marie-Tooth disease (CMT) facts medically edited on Oct. 28, 2015, by Charles Patrick Davis, MD, PhD
- Charcot-Marie-Tooth disease (CMT) is composed of types of inherited neurological disorders that affect
motor and sensory peripheral nerves (neuropathy), resulting in weakness in the musculature; the disease may get progressively worse over time. It is one of the most common (1 in 2,500 people) inherited neurological disorders. CMT is also known as HMSM (hereditary motor and sensory neuropathy) and peroneal muscular atrophy.
- Symptoms of Charcot-Marie-Tooth disease often begin in adolescence or early adulthood (some may occur early in life) and may include difficulty with
- breathing, and
- loss of muscle bulk, especially in the lower legs.
- The cause of Charcot-Marie-Tooth disease is inherited mutations in genes (also termed a hereditary motor and sensory neuropathy) that produce proteins that are involved in the structure of peripheral nervous system, specifically, axons or their myelin sheaths (myelin insulates and protects nerve cells); infrequently, Charcot-Marie-Tooth disease can occur with spontaneous mutation of the person's gene.
- There are many forms of CMT (for example, CMT 1-4, CMTX,
or type 1 or type 2); these forms or types are related to the mutations in the genes that alter the peripheral nerves and/or their myelin sheaths.
- Charcot-Marie-Tooth disease is diagnosed with the patient's medical history, family history, and neurological examination. The physical examination may reveal
- muscle weakness,
- decreased muscle bulk,
- leg pain,
- foot drop (inability to control position of the foot), and
- foot deformities such as hammertoes, high arches
in the feet, or inverted heels.
- Other tests such as nerve conduction studies, nerve, biopsy electromyography, and/or genetic testing also are available.
- Charcot-Marie-Tooth disease has no cure, but individuals may be helped
(treated) with exercise, stretching, plus physical and occupational therapy. Many patients may benefit from use of orthopedic items, such as ankle braces and other items (thumb splints to help hand weakness), to give support so the patient maintains mobility.
- The majority of patients have a normal life span, but a few do not and experience severe progressive disease.
- Diagnosis is done by the patient's family history, their physical exam, and symptoms; other tests may include nerve conduction studies, electromyography, or nerve biopsy to help distinguish CMT from other diseases like muscular dystrophies.
- The prognosis (outcome) varies with the disease severity and usually ranges from fair to poor, as the disease is progressive.
- Research is ongoing for Charcot-Marie-Tooth disease and includes gene therapy experiments, the use of nerve growth factors, vitamin C, and the use of curcumin (a component of curry) in animal models of this disease.
- A list of government and private organizations that can provide more detailed information about Charcot-Marie-Tooth disease and research on Charcot-Marie-Tooth disease is provided in this article.
What is Charcot-Marie-Tooth disease?
Charcot-Marie-Tooth disease (CMT) is one of the most common inherited neurological disorders, affecting approximately 1 in 2,500 people in the United States. The disease is named for the three physicians who first identified it in 1886 -- Jean-Martin Charcot and Pierre Marie in Paris, France, and Howard Henry Tooth in Cambridge, England.
CMT, also known as hereditary motor and sensory neuropathy (HMSN) or peroneal muscular atrophy, comprises a group of disorders that affect peripheral nerves. The peripheral nerves lie outside the brain and spinal cord and supply the muscles and sensory organs in the limbs. Disorders that affect the peripheral nerves are called peripheral neuropathies.