Charcot-Marie-Tooth disease

　　First, the cause of the disease

　　The disease is mainly caused by genetic factors, CMT1 and CMT2 are both autosomal dominant inheritance patterns, and there may be sporadic cases.

　　1, CMT1 type:The CMT1A disease-causing gene is located at 17p11.2-12, encoding peripheral nerve myelin protein 22 (PMP22). The gene duplication mutation leads to overexpression, causing an increase in PMP22 protein; a small number of patients are caused by mutations in the PMP22 gene, producing abnormal PMP22 protein leading to the disease;

　　2, CMT2 type:The CMT2A gene is located on chromosome 1p35-36, CMT2B on 3q13-22, CMT2C on 5q, CMT2D on 7p14, CMT2E on 8p21. CMT also has X-linked dominant (CMTX) and chromosome recessive (CMT4) modes.

　　Second, pathogenesis

　　1. Genetic mode

　　(1) CMT1 type: It can be inherited in two ways, autosomal dominant, recessive, and X-linked dominant or recessive. Recent studies have shown that CMT1 can be divided into 1A, 1B, and 1C types. CMT1A is the most common (56% to 60%), caused by a mutation in the PMP-22 gene on chromosome 17P11.2-12. CMT1B is rare (30%), and the pathological gene is located at 1q21-23, related to the mutation of the myelin protein P0 (MPZ) gene. The pathological gene of 1C is unknown to date, and the X-linked pathological gene is located at Xq13-1.

　　(2) CMT2 type: There are three types of genetic modes, usually autosomal dominant, recessive, and X-linked inheritance. The autosomal dominant pathological gene of this disease is located at 1p35-36, and the autosomal recessive and X-linked pathological genes are unknown.

　　2. Pathological changes

　　(1) CMT1 type: The biopsy results of CMT1 are mainly a significant reduction in the number of large and medium-sized fibers, intramuscular collagen hyperplasia. With the increase in age, the density of myelinated fibers progressively decreases, and demyelination becomes more severe. Due to the enhanced segmental demyelination and remyelination process, Schwann cell hyperplasia and endoneurial components form a concentric 'onion bulb' structure around the axon. There is posterior cord degeneration in the spinal cord, with the fasciculus gracilis being more obvious than the fasciculus cuneatus.

　　(2) CMT2 type: The pathological change of CMT2 is mainly axonal degeneration, with insignificant demyelination. Schwann cell hyperplasia presents as 'onion bulb' changes and is very rare.

　　This disease often has symptoms such as swelling, cyanosis, ulcers, and nerve nutritional disorders. Occasionally, there may be optic atrophy, changes in the pupil, nystagmus, and trigeminal neuralgia. In the later stage, the interosseous muscles of the hands may atrophy, along with the muscles of the hypothenar and thenar eminences, forming an ape-like hand deformity. However, the atrophy generally does not extend above the elbow joint. The injury to the legs starts from the gastrocnemius muscle, and then gradually extends to the interosseous muscles, the flexor muscles of the lower leg, and finally involves the lower third of the thigh muscle. However, the upper part is completely normal, forming a 'crane's leg' or inverted bottle-shaped deformity. The atrophied muscles may have fasciculation, and the Achilles reflex may be weakened or disappear early. Due to the weakness of the foot dorsiflexion, it often presents with an equine valgus deformity.

　　It is a typical case of Charcot-Marie-Tooth disease (CMT). The lower limbs present an inverted bottle shape, also known as cranes' legs, accompanied by high arches, claw toes, equine valgus deformity, and other malformations. When walking, it exhibits a special gait of leaping. There are symptoms such as muscle weakness, atrophy, fasciculation, and decreased or absent tendon reflexes. The onset is in the muscles of the hands and forearms, and atrophy of the distal muscles of the lower limbs is only seen in a few cases. The extremities may appear with glove or sock-like sensory disturbances and a series of autonomic and nutritional metabolic disorders. Local skin may appear cyanotic, with low skin temperature and ulcer formation.

　　How should muscular atrophy of the fibula be prevented?

　　What kind of laboratory tests should be done for muscular atrophy of the fibula muscle?

　　Laboratory examination:

　　1. Cerebrospinal fluid examination: most are normal, a few may have increased protein content. Electromyography examination shows denervation changes in atrophic muscles, with a decrease in the conduction velocity of the limbs (NCV), even disappearance, more obvious in the lower limbs than in the upper limbs, and the conduction velocity of motor nerves is more obvious than that of sensory nerves. In familial cases, NCV changes are similar within the same family, and there are many differences between different families. Some patients have abnormal visual, auditory, and somatosensory evoked potentials, indicating involvement of the central nervous pathway.

　　2. Serum protein electrophoresis: routine examination should be performed for idiopathic peripheral neuropathy of unknown cause.

　　3. There may be a significant increase in serum phytanic acid levels, with an increase in fatty acids of 10% to 20%. Blood cholesterol, high-density lipoprotein, and low-density lipoprotein are moderately reduced.

　　First, the dietary therapy of muscular atrophy of the fibula muscle

　　1. Yam Sparerib Soup

　　Ingredients: yam, spareribs, scallion, ginger, salt, yellow wine.

　　Preparation:

　　(1) Wash the yam, peel and cut it into pieces, and steam for 2 minutes.

　　(2) Wash the spareribs, fill the sand pot with water, bring to a boil, and skim off the foam.

　　(3) Add ginger slices and scallion bundles, add yellow wine, and turn the heat to low.

　　(4) Boil for an hour, remove the scallion bundle, add yam, and then turn the heat to medium and then to low after boiling.

　　(5) After half an hour, add an appropriate amount of salt, continue to stew for half an hour until the yam and spareribs are tender and soft.

　　2. Zishen Field Chicken Congee

　　Main ingredients: 100 grams of glutinous rice, 200 grams of field chicken.

　　Accessories: 50 grams of lean pork, 30 grams of Taiizi参, 20 grams of dried lily, 10 grams of green beans.

　　Seasonings: 5 grams of scallion, 2 grams of salt, 3 grams of sesame oil, 6 grams of starch (from soybeans), 5 grams of cooking wine, 1 gram of monosodium glutamate.

　　Preparation:

　　(1) Wash the glutinous rice, soak it in cold water for half an hour, remove it, and drain the water.

　　(2) Peel and clean the field chicken, then cut it into pieces.

　　(3) Wash the lean pork, slice it, add starch, cooking wine, and monosodium glutamate, and marinate for 15 minutes.

　　(4) Wash the lily, tear it into petals; wash Taiizi参 and cut it into pieces; wash the green beans.

　　(5) Put the glutinous rice into the boiling water pot, boil it, add Taiizi参, lily, and green beans, then boil it with high heat, add lean pork and field chicken, and cook it with low heat until the congee is done. Sprinkle with chopped green onions, salt, and monosodium glutamate, pour in sesame oil, and it is ready to serve.

　　2. What is good for the body for patients with muscular atrophy of the fibula muscle?

　　1. It is recommended to eat more foods rich in vitamin B and vitamin E.

　　2. In daily life, chickens, ducks, and fish can all be eaten.

　　3. It is recommended to choose high-protein, high-vitamin, and easily digestible foods, and increase the appetite of patients through reasonable nutrition and appropriate cooking as much as possible to meet the nutritional and energy needs of the body.

　　Third, what is not good for the body of排骨肌萎缩症 patients

　　1. Avoid spicy, fatty, and刺激性 foods in the diet, and avoid seafood with fishy smell such as shrimps, crabs, clams, and snails.

　　2. Avoid various seasonings containing glutamic acid, such as monosodium glutamate, chicken essence, Wang Shouyi Thirteen Spices, and Fifteen Spices.

　　3. Avoid foods containing glutamic acid, such as instant noodles, biscuits, and other food additives.

　　4. Avoid spicy foods, such as chili.

　　5. Quit smoking and drinking.

　　This disease is a group of genetic diseases, and the only effective preventive method is prenatal genetic diagnosis. By genetic diagnosis, determine the genotype of the proband, analyze the fetal genotype using fetal villi, amniotic fluid, or umbilical cord blood, and determine prenatal diagnosis and terminate pregnancy.

      Western Treatment Methods for排骨肌萎缩症

　　1. Treatment

　　Currently, there is no specific treatment method, mainly对症 treatment. Medications such as B vitamins, vitamin E, citicoline, ATP, coenzyme A, and nerve growth factors can be used to promote the improvement of neurological function. Patients with foot drop or equinovarus deformity can undergo orthopedic surgery or wear orthopedic shoes, and undergo limb functional training. Pay attention to limb warming and avoid heavy physical labor.

　　The natural course is usually slow but does not affect life. Due to the mild involvement of proximal muscle strength, walking ability is rarely completely lost. CMT4 type can adopt dietary therapy, limit the intake of phytanic acid to alleviate the symptoms of peripheral nerves and cerebellum, and prevent the progression of the disease. Milk, butter, eggs, and vegetables and fruits rich in chlorophyll contain a high amount of phytanic acid, and the intake should be limited.

　　2. Prognosis

　　The prognosis of this disease is generally good, the course of the disease progresses extremely slowly, and patients can still survive for decades after onset. This disease can cause sudden death due to acute heart failure caused by heart damage.