Proximal spinal muscular atrophy type 2 3. Types of sma

Genetic diseases are the most insidious, because it is not clear when such a disease will occur. Spinal muscular atrophy is one such disease. This disease is considered rare, since one case of the disease occurs in 6-10 thousand people. healthy people. With this ailment, the patient's lower limbs suffer, while the hands remain practically untouched. But first things first…

So, spinal muscular atrophy includes several diseases that differ in the variant of the occurrence and nature of the course of diseases. This type of disease was first described in 1891 by the scientist Werdingt. In the future, his research was supplemented by a description of the disease by another specialist - Hoffman. As a result, the most common muscular atrophy in children is called Werding-Hoffman amyotrophy.

Causes

As mentioned earlier, the disease is inherited, and the main causes of development are genetic mutations. As a result, the production of a special protein responsible for the functioning of motor neurons stops. Thus, those neurons that have managed to form and begin their full-fledged activity are destroyed, and this leads to the impossibility of transmitting nerve impulses and, as a result, a violation or complete absence muscle control.

For the formation of the disease, it is necessary that the mother and father were carriers of the wrong gene. In this case, muscle atrophy develops in a child with a probability of 25%.

To the question of the presence of the wrong gene in the body of parents: every 50 people are carriers of this gene.

Classification

In modern neurology, there are four main types of disease, which include:


Werding-Hoffmann disease

The most terrible type of disease that affects infants under the age of six months. The lethality of the disease is almost 100%, if the disease manifested itself before 3 one month old the newborn dies within 6 months. When diagnosing an illness after 3 months, there is a chance that a small patient will live from 2 to 9 years.

There are three types of disease (congenital, early and late)

congenital type

This form of the disease occurs in early childhood(up to 3 months) and during prenatal development fetus. When the fetus is in the mother's abdomen, the disease is characterized by weak movements of the child. Death occurs before 1.5 years. hallmark- pose of a frog (divorced to the sides and bent at the elbows and knees of the limb).

early type

This form develops after a year and a half and the main impetus to its progression is the transferred infection. Death occurs before 5 years of age. The child gradually loses all acquired skills.

late type

This variant of the course of the disease has almost the same symptoms as the first two, with the exception of a longer period of disease progression. It is diagnosed in babies after 5 years of age, and the lethal outcome occurs by the age of 15–18. The patient loses the ability to walk independently between 10 and 12 years of age.

The symptoms of Werding-Hoffmann disease are as follows:

  • problems with sucking and swallowing (there is a possibility of food getting into respiratory system, which is fraught with the development of pneumonia and death);
  • the presence of the effect of a "traveling wave" in the baby's tongue is noted;
  • involuntary contraction of the muscles of the tongue is called fasciculation;
  • apathy of the baby (manifested in behavior and sluggish cry);
  • respiratory failure (occurs as a result of atrophy of the intercostal muscles and diaphragm);
  • violations of motor development (lack of skills of holding the head, sitting and turning over).

The disease is also insidious in that it completely eliminates the developed skills of the baby. For example, if the baby has learned to hold his head or roll over, these skills will be completely lost.

Often, muscle atrophy in children develops in parallel with other disorders in the body, for example:

  • oligophrenia;
  • small skull;
  • undescended testicles;
  • heart disease;
  • clubfoot;
  • congenital fractures;
  • hemangioma.

The lethal outcome is associated primarily with concomitant diseases.

Dubovitz disease

Type 2 disease or Dubovitz's disease is an intermediate form of the disease and manifests itself in babies aged 6 months to 2 years. The survival rate of sick children is also low, and the average life expectancy with such a diagnosis is 13–15 years.

The disease manifests itself, like the first type, suddenly and has the following symptoms:

  • loss of tendon reflexes;
  • hand tremor;
  • drooping head (associated with weak neck muscles);
  • deformation bone department(eversion hip joint, the development of scoliosis, and possibly the formation of "chicken" chest);
  • fasciculation of the tongue;
  • bulbar paralysis;
  • trembling fingers.

The development of this muscle atrophy, as a rule, develops according to the standard scenario. First, the lower extremities (thighs) are affected and gradually the disease progresses upwards.

Spinal muscular atrophy types 1 and 2 are similar in that all the skills acquired by the child are gradually lost.

Kugelberg-Welander disease

Muscular atrophy type 3 or Kugelberg-Welander disease ( juvenile disease) differs from the first two more favorable prognosis regarding mortality. The defeat of the body occurs in the period from 1.5 to 12 years. The life expectancy of such patients is up to 25–40 years, with proper care and proper treatment.

The difficulty in detecting the disease from the very beginning of its progression lies in the presence subcutaneous fat, which somewhat cancels out Negative influence muscle atrophy, but not for long.

The disease begins to progress already at the age when the baby has learned to walk, and, accordingly, the first blow falls on this skill. At first, the little patient begins to walk as clockwork doll. Often stumbles and gradually the skill of walking is lost. In the future, the movement of the patient without the help of a wheelchair or a special cane is unlikely.

Nevertheless, in more than 60% of cases it is impossible to speak of complete disability. The nature of the lesion is such that the patient is able to independently (without outside help) to move around, and even work in enterprises for people with disabilities.

The order of inheritance of the disease

The main symptoms of this disease include:

  • scoliosis;
  • tremor of the upper limbs;
  • convulsive manifestations of the lower extremities;
  • chest deformity;
  • joint contracture;
  • trembling fingers;
  • fasciculation of the tongue;
  • bulbar syndrome.

The patient loses the ability to move normally at the age of 10–12 years.

adult atrophy

Type 4 of this disease is not in vain called the adult disease, as it affects mainly people over 35 years old. It is characterized by a gradual loss of the ability to move independently, due to atrophy of the muscles of the lower extremities.

This type of disease does not affect the life expectancy of the patient.

In addition to the above ailments, there are several amyotrophies, including:

  1. Kennedy's bulbospinal amyotrophy (characteristic only for males over 30 years of age. It manifests itself as a gradual violation of the motor functions of the legs for 10–20 years. In addition, it can manifest itself by trembling of the upper limbs and head, and endocrine system disorders).
  2. Distal spinal Duchenne-Aran atrophy (characterized by the formation of the so-called skeletal arm. As a result of the development of the disease, the hands suffer, and progresses to the forearm. The course of the disease is favorable, with the exception of accompanying development Parkinson's disease or torsion dystonia).
  3. Scapulo - Vulpian's peroneal amyotrophy (characterized by a rather slow course. The patient has the ability to move independently up to 40 years. Progression begins from the upper limbs as a result of development, pterygoid scapulae are formed, after which the disease affects the muscle groups responsible for flexion and extension of the feet and legs).

Diagnostics

For precise setting diagnosis little analysis clinical picture development of the disease, it is necessary to comprehensive research, which includes:

  1. Study of the patient's history.
  2. Electrocardiogram (ECG).
  3. Biopsy of skeletal muscles.
  4. Genetic research.

The complex of these studies allows you to accurately diagnose and draw up a treatment plan. As for young parents, passing a genetic examination when planning a pregnancy, if there are relatives who suffered from such a pathology, is a prerequisite. In case of detection of an ailment in the fetus, in 99% of cases, the pregnancy is terminated.

What happens to the spine

Treatment

Treatment for spinal muscular atrophy is aimed at relieving general condition sick, because effective measures to eliminate the disease has not been identified. Research is currently underway to stimulate the production of a special protein that is responsible for neural connection but the results are far from ideal.

What does the therapy include:

  • a course of drugs for the metabolism of nerve tissues and muscles (Cerebrolysin, Cytoflavin, Glutamic acid);
  • B vitamins;
  • anabolic steroids (retabolil, nerobol);
  • drugs to improve the passage of nerve impulses (prozerin, dibazol, galantamine);
  • massage;
  • physiotherapy;
  • physiotherapy procedures;
  • orthopedic correction of the spine;
  • neuromuscular stimulation;
  • special diet.

A special style of eating…

To special diet in this disease are good nutrition, fat rich, carbohydrates, amino acids and minerals

The disease is associated with muscle function, and therefore implies the need to feed them with amino acids. Foods rich in amino acids:

  • cereals and legumes;
  • mushrooms;
  • almost all types of nuts;
  • meat dishes;
  • fish dishes;
  • eggs;
  • dark rice;
  • dairy products;
  • wheat dishes;
  • chicken fillet;
  • oats.

In addition, the use of anabolic steroids is not enough, to make up for the so-called deficiency, you can use foods that promote natural muscle growth, including:

  • herring;
  • grapefruit;
  • yogurt;
  • green tea;
  • coffee;
  • broccoli;
  • tomatoes;
  • parsley and spinach;
  • garlic and onions;
  • watermelon;
  • blueberry;
  • sunflower seeds.

An additional source of L-carnitine is:

  • liver;
  • beef, veal;
  • pork;
  • turkey;
  • goose;
  • duck;
  • sour cream, cream and milk.
  • parsnip;
  • horseradish root;
  • parsley;
  • ginseng;
  • dill;
  • bee pollen;
  • lean meat;
  • homemade alcohol in a small amount.

Undoubtedly, for a better assimilation of all of the above, it is necessary to use vitamin complexes including vitamins B, E, C.

Prevention

Due to the special nature of the manifestation of the disease, preventive actions are somewhat limited, and they can only include explaining to future parents the severity of the consequences at the birth of a sick child. Up to 14 weeks, it is possible to decide to terminate the pregnancy.

So, spinal muscular atrophy is hereditary incurable disease severe course and it requires close attention. You should not leave the solution of the discovered problem to chance, but it is better to trust a specialist. Take care of your children and loved ones, do not self-medicate, especially such dangerous ailments.

SMN-associated SMA, or 5qSMA, or proximal SMA is generally classified into three categories. It is conditionally possible to single out CMA0 (zero) and CMA4. Thus, there are several main types of SMA, and they all proceed differently. The process can develop at different periods of life, have its own clinical features, its own course, prognosis, and the necessary amount of help and support.

Type 1– the heaviest, with the earliest debut, type 3- the least severe late age start. Some experts distinguish another type 4 to denote moderate or mild SMA with onset in adulthood.

The specificity of the disease is that in each child, even within the same group, SMA proceeds differently, individually. Outwardly, this is manifested in the possible range of movements - some children are able to hold their heads, raise their arms a little and raise their legs, while others simply lie in the classic “frog” position and can only slightly move their feet and fingers.

Victor Dubovitz, one of the luminaries in the field of SMA management, in the 90s proposed, in addition to ordinary classification use a more sophisticated scale. For example, there is CMA1 and its subtypes will be 1.1, 1.2, 1.3, i.e. from 1.1 to 1.9. This scheme is used in Italy.

The American system is based on the ABC scale, where B is the classic type, A is the weak type, and C, respectively, is the stronger type. The system with ABC subtypes clearly describes the SMA clinic and allows you to select maintenance therapy for the child depending on the subgroup and the corresponding prognosis. This system is beginning to be used in Russia and other countries.

Important! A genetic test does not determine the type of SMA. The type is set based on functionality child.

CMA0

Symptoms of the disease manifest themselves in utero in the absence of motor activity in the fetus. From birth, the child has expressed generalized muscular hypotension with a characteristic “frog” posture, spontaneous physical activity. Tendon reflexes are not elicited.

As a rule, these children are observed by pediatricians and neurologists for a long time with a diagnosis of perinatal encephalopathy. Sometimes doctors associate the symptom complex of a sluggish child with a difficult birth. But all children perinatal encephalopathy and with the consequences of difficult childbirth, they adapt quickly and well, gradually improve, in contrast to children with SMA.

The prognosis is extremely unfavorable - children die, as a rule, at a very early age (up to six months) from intercurrent diseases (complicating the course of the underlying disease).

Usually CMA0 and CMA1 are combined.

CMA1

With type I spinal muscular atrophy (Werdnig-Hoffmann type) mother already during pregnancy can pay attention to the late and weak movement of the fetus. From birth, the child has a widespread decrease in muscle tone (the "sluggish baby" syndrome). From the first months of life, weakness and atrophy of the muscles of the upper and lower extremities appear, followed by involvement of the muscles of the trunk and neck. Such muscle changes lead to the fact that children cannot sit. Muscle atrophy and twitching muscle fibers usually masked by well-defined subcutaneous fat. characteristic symptom is a small trembling (tremor) of the fingers of outstretched handles. Sometimes twitching of the muscles of the tongue is found.

A typical symptom is also the weakening or complete disappearance of tendon reflexes (knee, Achilles), limitation normal mobility in the joint, skeletal deformities. Due to the weakness of the intercostal muscles, the child's chest becomes flattened. Since as a result of muscle weakness there is not sufficient ventilation of the lungs, frequent respiratory infections, there are various respiratory disorders. mental development children are not affected.

Infants may experience respiratory problems and inability to eat. Congenital contractures varying in severity from simple clubfoot to generalized arthrogryposis (multiple congenital pathology movement apparatus, manifested by numerous contractures of the joints, muscle hypotrophy and lesions spinal cord), occur in approximately 10% of severely affected neonates. Children infancy lie in a relaxed “frog” position, spontaneous motor activity is reduced, children cannot overcome the gravity of the limbs, they do not hold their heads well.

Usually, except in very rare, severe cases, the diagnosis of SMA is not made in the hospital. The child is discharged home healthy, and when parents notice a low muscle tone, they either do not attach serious importance to this if they do not know how to move healthy baby, or calm down with the advice of a doctor in a clinic: “Don’t worry, everyone develops in their own time, they will still get up and run.” Parents may not understand the severity of the problems, this should be seen by the doctor, but, unfortunately, in polyclinics, the symptoms of SMA are poorly known.
These children show the first signs of the disease before the age of 6 months. This means that they do not acquire the skills to sit, crawl, walk on their own. As a result, the range of motion in such children is very small. At the same time, SMA does not affect the cognitive sphere, children understand everything, and sensitivity is not affected. If you deal with them as with ordinary children - play, read, collect pyramids - then these children develop absolutely normally mentally and mentally, and all developmental delays that neurologists can put on them are associated with impaired motor activity and conditions in which which they are.

More than 2/3 of children with this disease die before 2 years of age, in many cases death occurs at an early age. infancy in connection with the defeat of the respiratory muscles and the occurrence of various complications from the lungs.

CMA2

With type II spinal muscular atrophy, the disease first manifests itself somewhat later (in the first 1.5 years of a child's life) and is characterized by a slower course. The main sign is the inability of the child to stand up.

Children with SMA2 are usually able to suck and swallow, and respiratory function is not impaired in early infancy. Nasal tone of voice and swallowing disorders appear at an older age. Despite progressive muscle weakness, many of them survive to school age and beyond, although late stages diseases, there is a severe degree of disability, and children need wheelchairs. Ordinary strollers are not suitable for them, additional supports, stops, special devices are needed that optimally fix the position of the body.

In many patients with a long life expectancy, one of the main complications of the disease is scoliosis and contractures, which develop very quickly. Even in bedridden children, scoliosis develops quite significantly, the curvature of the spine occurs not from stress, but from weakness.

Children with SMA2 are stable enough for a period of time that parents can maintain the set of skills that these children have already acquired.

There is such a term “disease plateau”, which means a certain period during which children are quite stable, and there is no significant deterioration in the condition, progression of the disease. It may look like this: children gain skills, like all ordinary children, when the disease “starts”, they stop developing, and then the regression of their condition can go very slowly or, conversely, very quickly, each child has his own way. Or so: children gain skills for a certain time, then some event or illness occurs, some of the skills are lost, and then a rather long “plateau” sets in, during which there may even be slight improvements, but then inevitable deterioration occurs. The rate of progression of the disease, the duration of the "plateau" (or lack thereof) and subsequent deterioration - all this is very individual.

CMA3

Kugelberg-Welander disease- most mild form spinal muscular atrophy (SMA type III). It begins at the age of 1.5 to 17 years. With such a disease, people live longer, the progression is slow. Muscle atrophy begins with the legs and then spreads to the arms. In infancy clinical manifestations disease may not be present. Progressive weakness develops in the proximal limbs, especially in the muscles of the shoulder girdle. Patients retain the ability to walk independently. Symptoms of weakness of the muscles of the bulbar group are rare. Approximately 25% of patients with this form of SMA have more muscle hypertrophy than muscle atrophy; therefore, muscular dystrophy can be misdiagnosed. Patients may live to adulthood.

SMA in this large group of children is detected at the age of over one and a half years, i.e. The child is usually able to walk independently. The disease manifests itself so individually that the diagnosis can be made at a year and a half, or maybe at nine years. Depending on this, there will be different forecasts both in terms of duration and quality of life.

In children with SMA3, life expectancy is almost the same as the standard one, they live up to 30 and 40 years. Their symptoms do not progress so quickly, but these children also need to be given rehabilitation and physical therapy classes.

Now there's enough a large number of adult patients with SMA, and this is not the fourth type, these are children with SMA2 and SMA3 who have grown up. They have big problems that are not related to movement and breathing. No matter how long they live, 20 years or 30, they are already disillusioned with medicine, because no one knows what to do with them. Every mother of a child with SMA and every adult patient with SMA can tell about the same story about a doctor’s appointment: “Don’t come to me, we don’t know what to do with you”; "You're not dead yet, ah, wow." Indeed, doctors do not know what to do with these patients, and they say: “Well, what you want from me is not being treated, to be honest, I don’t know what to do with you.” Nobody deals with them, after 18 years they don’t know what to do with them at all.

These patients (often invisible patients because they stay at home) do not believe in medical care because they have been brushed aside all their lives. And they seek help only when it is no longer possible to ignore the symptoms, when strong pain, i.e. late - almost already on his deathbed. Until recently, there was no work with this category of patients. Now there is an opportunity to somehow improve the situation, more assistance is provided charitable foundations more attention is being paid to this issue.

SMA3 disease does not develop very rapidly, gradually there is a general weakening of the body and a slow loss of acquired skills.

CMA4

The fourth type of SMA occurs in people over 25 years of age. The disease develops rather slowly, with virtually no effect on life expectancy. With SMA4, tremors can develop, a general weakening, including muscle strength, can occur. Over time, SMA4 can lead to loss of the ability to move independently.

Spinal amyotrophy of Werdnig-Hoffmann (acute malignant infantile spinal amyotrophy of Werdnig-Hoffmann, type I spinal amyotrophy) is a hereditary disease nervous system characterized by the development muscle weakness in almost all muscle structures of the body. It leads to a violation of the ability to sit, move and self-service. effective means there is no cure for the disease. Prenatal diagnosis helps to avoid the birth of a sick child in the family. From this article you can learn about how this disease is inherited, how it manifests itself and how such patients can be helped.

The disease is named after the two scientists who first described it. AT late XIX century Werdnig and Hoffman proved the morphological essence of the disease. They assumed the only similar form diseases. However, in the 20th century, Kukelberg and Welander described a different clinical form spinal amyotrophy, which had the same genetic cause as Werdnig-Hoffmann spinal amyotrophy. To date, the concept of spinal amyotrophy combines several clinically distinct forms of the disease. But they are all associated with the same hereditary defect.

Causes of spinal amyotrophy

The disease is hereditary. It is based on genetic mutation on the 5th human chromosome. The gene responsible for the production of the SMN protein undergoes mutation. The synthesis of this protein provides normal development motor neurons. In the case of the development of a mutation, motor neurons are destroyed or are underdeveloped, which means that the transmission of an impulse from nerve fiber to the muscle is impossible. The muscle doesn't work. Consequently, all movements associated with a non-working muscle are not performed.

The wrong gene has an autosomal recessive pattern of inheritance. This means the following: in order for spinal amyotrophy to develop, two mutant genes from the mother and from the father must match. That is, the mother and father of the child must be carriers of the pathological gene, but at the same time they are not sick due to the simultaneous presence of a healthy dominant (predominant) gene in them (each person has paired genes). If the mother and father are carriers of the pathological gene, then the risk of having a sick child is 25%. It is estimated that approximately one in 50 people on the planet is a carrier of the mutated gene.


Symptoms

To date, 4 forms of spinal amyotrophy are known. All of them differ in terms of the onset of the disease, some symptoms and life expectancy. Common to all forms is the absence of sensory and mental disturbances. Functions pelvic organs never suffer. All symptoms are associated only with the defeat of the motor sphere.

Spinal amyotrophy type I


The onset of the disease before the age of 6 months is extremely poor prognosis.

There may be violations of sucking and swallowing, difficult movements of the tongue. The tongue itself may show fasciculations (involuntary muscle contractions, “waves” running through the tongue) and appear atrophied. The cry of the child is sluggish and weak. If the pharyngeal reflex is reduced, then there are problems with feeding, as a result of which food enters the Airways. And this causes aspiration pneumonia, from which the child can die.

Damage to the diaphragm and intercostal muscles is manifested by a violation of the act of breathing. Initially, this process is compensated, but gradually the respiratory failure worsens.

It is characteristic that the mimic muscles of the face and the muscles responsible for eye movements are not affected.

Such children lag behind in motor development: they do not hold their heads, do not roll over, do not reach for an object, do not sit. If some motor skills could be realized before the onset of the disease, then they will be lost.

Except movement disorders the disease is characterized by deformity of the chest.

If signs of the disease are visible immediately after birth, then such children often die within the first 6 months of life. If signs appear after 3 months, then the life span is somewhat longer - about 2-3 years. Inevitably, an infection accompanies due to respiratory disorders from which such children die.

Spinal amyotrophy may be associated with birth defects development: oligophrenia, small skull, heart defects, congenital fractures, hemangiomas, clubfoot, undescended testicles.

Spinal amyotrophy type II

This form of the disease occurs between the first 6 months and 2 years of life. Prior to this, the child does not reveal any violations. He begins to hold his head in time, roll over and sit, and sometimes even walk. And then gradually there is muscle weakness. It usually starts with the thigh muscles. Slowly, walking becomes impossible, they decrease and are lost. Muscle weakness progresses slowly. All limbs are involved. Muscle atrophy develops. The process can also capture the respiratory muscles. Also, as with Type I spinal amyotrophy, facial muscles and eye muscles are not affected. Perhaps trembling of the hands, twitching in the tongue and limbs. Weakness of the neck muscles is manifested by drooping of the head.

Very characteristic are osteoarticular deformities: scoliosis, funnel chest, dislocation of the hip joint.

This form has a more benign course than type I spinal amyotrophy, but most patients have respiratory problems by adolescence. Poor chest excursion contributes to the attachment of infections from which the child may die.

Spinal amyotrophy type III

This form is described by Kukelberg and Welander. It is considered juvenile spinal amyotrophy. The onset of the disease is between 2 and 15 years of age.

The first symptom is always unsteady walking due to increasing weakness in the legs. The tone in the legs decreases, muscle atrophy develops (muscles become thinner), but this is not always noticeable due to the well-developed layer of subcutaneous fatty tissue by this age. Children stumble, fall, move awkwardly. Gradually, movements in the legs become impossible, and the patient stops walking.

Gradually, the disease also captures the upper limbs, the hands are affected later. With this form, weakness of the facial muscles develops, but eye movements persist in in full. There are no reflexes from those muscle groups that are already involved in the process.

Skeletal deformities are also characteristic: funnel-shaped chest, joint contractures.

This form of the disease during maintenance therapy allows patients to live up to 40 years.

Spinal amyotrophy type IV

This form of the disease is considered "adult", because it manifests itself after 35 years. Also, there is weakness in the muscles of the legs, a decrease in reflexes, muscle atrophy, which, in the end, leads to a complete loss of movement in the legs. At the same time, the respiratory muscles are not involved in the process, there are no respiratory disorders. Life expectancy in this form of the disease is almost the same as in healthy people. The course is the most benign in comparison with other forms.


Diagnostics

When symptoms similar to spinal amyotrophy appear, electroneuromyography is performed (spontaneous activity is detected in the form of fasciculation potentials at rest and an increase in the average amplitude of motor unit action potentials).

The final diagnosis is made after genetic research(DNA diagnostics): find a gene mutation on the 5th chromosome.

In families where there were cases similar diseases, carry out prenatal (antenatal) DNA diagnostics in the fetus. When a pathology is detected, the issue of termination of pregnancy is decided.


Principles of treatment of spinal amyotrophy

Unfortunately, this is an incurable hereditary disease. At the present stage, research is being carried out that may help regulate SMN protein synthesis, but there are no results yet.

To alleviate the condition of patients with spinal amyotrophy help:

Spinal Werdnig-Hoffman amyotrophy, like other forms of this disease, is a pathology that is inherited. The appearance of the disease in a child is explained by the presence of a mutant gene in both the mother and the father. The disease is characterized mainly by muscle weakness, which causes immobility and respiratory disorders. The disease is currently incurable.


Spinal muscular atrophy (SMA), or spinal Werdnig-Hoffmann amyotrophy, is autosomal recessive hereditary disease which is characterized by progressive hypotension and muscle weakness.

The characteristic weakening of muscle tissues is due to the progressive degeneration of alpha motor neurons in the anterior horns of the spinal cord. Thus, the basis of the disease is the pathology of the spinal cord, which can be inherited.

A feature of the disease is a more active manifestation of weakness in skeletal muscles located more deeply than those located closer to the surface of the body. In this material, we will talk about the symptoms and treatment of Werdnig-Hoffmann spinal muscular atrophy.

The information will be useful to everyone who, for a number of reasons, had to deal with this serious, often fatal disease.

In some patients in pathological process cranial motor neurons may also be involved, especially in pairs V through XII. In this case, the disease originates from dorsal horn cells of the spinal cord, which in addition to everything causes insufficiency of the muscles of the diaphragm, gastrointestinal tract, heart and sphincters.

In 1890, Werdnig first described the classic infantile form of SMA, a manifestation of the syndrome in children. early age. Many years later, in 1956, Kugelberg and Welander classified less severe form spinal muscular atrophy in older patients.

Thanks to these scientists, physicians today can accurately differentiate SMA from different types diseases with similar symptoms, for example, muscular dystrophy Duchenne.

Spinal amyotrophy is the most common diagnosis in girls, with severely progressive weakness. This is one of the most common genetic reasons death in children.

The SMA syndrome is divided into four types based on the age of the patient as follows:

  • Type I (spinal Werdnig-Hoffman amyotrophy). Develops before the age of 6 months.
  • Type II - at the age of 6 to 12 months.
  • Type III (Kugelberg-Welander disease) - aged 2 to 15 years
  • Type IV in adult patients.

Spreading

The incidence of the disease is approximately one case per 15-20 thousand people. If we talk only about newborns, then this figure will be approximately 5-7 cases per 100 thousand. Since spinal amyotrophy is a hereditary recessive disease, many parents may be carriers and not know about it.

The prevalence of SMA carriers is 1 in 80, in other words, every 80th family can have a child suffering from spinal muscular atrophy. This risk increases several times when both parents are carriers of the mutated gene.

Thus, SMA syndrome is the most common degenerative disease nervous system in children after cystic fibrosis and, as noted above, this is the leading hereditary cause infant mortality.

The lethal outcome is due to respiratory failure. The younger the patient in the early stages of the disease, the worse the prognosis. General average age at the time of death is about 10 years. The state of intelligence and other indicators psychosomatic development child does not affect the progression of the disease.

In contrast to younger patients, adult males are more likely to be affected than females by a ratio of about 2:1, with the clinical course being more severe in male patients. The increase in cases of the disease in women begins at about 8 years of age and boys "catch up" with girls at the level of 13 years of age.

Spinal muscular atrophy - symptoms

The first type of spinal muscular atrophy causes the first symptoms to appear before the baby is born. Most mothers report abnormal fetal inactivity in the later stages of pregnancy. Symptoms of SMA in newborns are quite obvious - the child cannot roll over on his own, and subsequently take a sitting position.

In addition, progressive clinical deterioration develops, which in the vast majority of cases ends lethal outcome. Death usually occurs from respiratory failure and its complications in patients at 2 years of age.

Patients with type 2 SMA develop normally during the first 4-6 months of life. They may be able to sit up on their own, but they will never be able to walk, in the future they will need disabled carriage for movement. As a rule, such children live much longer than patients suffering from Werdnig-Hoffmann spinal atrophy. Average term life - up to 40 years.

Patients with the third type of disease often have difficulty climbing stairs or standing up from the floor, primarily due to weakness of the hip extensors. Life expectancy is close to normal.

Learn more about the symptoms of SMA

Newborns with type 1 spinal muscular atrophy are inactive. They move their limbs with great difficulty, if at all. The hips are almost constantly bent, weakened and can be easily twisted by hand in different sides. The knees are also bent.

Because the external musculature is usually less affected, the fingers and toes move almost normally. Babies cannot control or raise their head. Areflexia (absence of reflexes) is observed in almost all patients.

Children with type 2 SMA are able to move their heads and 75% of these patients can sit up on their own. Muscle weakness worse in lower limbs than at the top. Reflex patella is absent. Older children may demonstrate biceps and triceps reflexes.

Scoliosis is the most common symptom SMA, and most patients develop hip dislocation, unilateral or bilateral. These signs develop before the age of 10 years.

Patients with type 3 spinal muscular atrophy disease can walk early in life and this ability can be maintained on an outpatient basis throughout adolescence. Weakness can lead to, as well as limited stamina of the body. One third of patients become wheelchair bound by the age of 40.

Treatment

There is currently no known medical treatment spinal muscular atrophy, so it is immediately worth noting that the survival rate among patients of early and middle age is quite low.

Because of their short life expectancy, newborns with Werdnig-Hoffmann spinal muscular atrophy require little orthopedic involvement due to their short life expectancy. Splinting is used in a case that is often observed with weakened muscle activity.

For patients with type II and III SMA, physical therapy can be used to treat joint contracture (restricted joint movement). For more radical treatment contractures surgical treatment is indicated.

As noted above, the most common orthopedic problem in SMA is scoliosis, which is often severe. The progression of the curvature of the spine is about 8° per year, despite the treatment with braces.

Segmental-type posterior fusion is often recommended for young patients in whom spinal curvature cannot be corrected with braces, and for patients older than 10 years with curvature greater than 40°.

Surgery should be delayed until medical point vision is possible. It should be kept in mind that curvature progression is slower in patients with type 3 SMA and appears more frequently at a later age.

Diet

Treatment for spinal muscular atrophy requires individual approach to the rationing of the patient's menu, which, unfortunately, is very often not observed by the attending physicians. Anthropometric indicators, blood composition and biochemical markers of muscle condition are important elements assessments in patients with SMA.

The peculiarity of the course of the disease in a particular patient may require intervention in his diet in order to affect the above indicators, since it is with the help of food that the muscles can be given those nutrients which are necessary for the patient in his case.

Of course, such an approach to the treatment of spinal muscular amyotrophy is relevant only when a diagnosis is made for the second or third form of the disease.

Physical therapy

Additional support for a patient suffering from spinal muscular atrophy of the second and third types is as important as diet. First of all, with the help of a normalized load, it is possible to prevent the progression of joint contracture, as well as maintain strength, endurance and independence in self-care.

Quite a significant role physical exercise play in the educational, social, psychological and professional activities of the patient, since he will have the opportunity to lead an almost normal life, like healthy people.

Spinal muscular atrophy (orspinal amyotrophy) is a group of hereditary diseases characterized by progression muscle weakness and atrophy of muscle fibers due to damage to motor neurons (motor nerve cells) in the spinal cord or brain. The incidence of this pathology is about 1 case per 6-10 thousand newborns. At the same time, every second child with spinal muscular atrophy does not live up to 2 years.

Causes

The cause of spinal muscular atrophy is a mutation of the gene responsible for the synthesis of the SMN protein, localized on chromosome 5q. This defect subsequently leads to gradual death motor neurons of the anterior horns of the spinal cord and brain stem, as a result of which the respiratory, swallowing muscles, as well as the muscles of the face and body are affected (reduced muscle tone) and eventually atrophy. Most forms of spinal amyotrophy (childhood forms) are inherited in an autosomal recessive manner, that is, the disease is possible if both parents are carriers of the defective gene. However, the adult form (type IV) is linked to the X chromosome, and therefore only males are affected.

Symptoms of spinal muscular atrophy

Clinical manifestations of spinal amyotrophy depend on the form of the disease. common features of all forms of spinal muscular atrophy is a manifestation of general and muscle weakness, the preservation of sensitivity and intelligence, a decrease or absence of tendon reflexes.

The mildest course of childhood forms is characteristic of type III spinal muscular atrophy (Kugelberg-Welander syndrome). The first manifestations, as a rule, are found in children after 1.5 years and are characterized by difficulties with complex motor skills (running, climbing stairs, etc.). Symptoms progress slowly, swallowing and chewing disorders develop much later.

Type II spinal amyotrophy is characterized by an earlier manifestation (6-18 months) and a chronically progressive course. In such children, there is a lag in motor development, tremor of the fingers, progression of the weakness of the cough reflex, shallow diaphragmatic breathing and intercostal muscles. Initially, children with this form of the disease can crawl, sit unsupported, and some even stand with support, but these abilities are lost as they grow and gain weight. Skeletal and muscular deformities develop (including scoliosis, chest deformities, and pseudohypertrophy) calf muscle), contractures, as well as respiratory disorders (up to the development of respiratory failure).

Most severe form is type I spinal muscular atrophy (Werdnig-Hoffmann syndrome), manifesting in early childhood (in the first 6 months). The “flaccid child” syndrome is characteristic (weak cry, reduced motor activity, sluggish sucking, weight loss, reduced swallowing, sucking and cough reflexes). Such children are unable to hold the head, roll over and sit, lag behind in motor development (gross delay). Deformities of the joints and limbs, contractures, respiratory and bulbar disorders may develop. The average life expectancy of such children is 2 years. The cause of death is usually severe respiratory failure or the development of pneumonia.

adult form(type IV) has a mild course, in which the muscles of the shoulder girdle are most often affected first.

Diagnostics

Diagnosis of spinal muscular atrophy includes a neurological examination, biochemical analysis blood (creatine kinase may be slightly increased), electroneuromyography (a decrease in nerve impulses with normal sensory nerve conduction is determined), bone radiography (presence of deformities), muscle biopsy (atrophy muscle tissue), as well as genetic testing.

Classification

There are the following forms of spinal muscular atrophy:

Type I - infantile (Verdnig-Hoffman disease);

Type II - intermediate (Dubovitz's disease);

Type III - juvenile (Kyugelberg-Welander disease);

IV type - adult.

Patient's actions

If there is a suspicion of muscle weakness, it is recommended to consult a specialist (geneticist and neurologist).

Treatment of spinal muscular atrophy

Specific therapy that can cure this pathology, not yet developed. However, there was a slight slowdown in the rate of progression of symptoms with the use of B vitamins and medicines that improve trophism nervous tissue. Otherwise, palliative support is indicated to improve the quality of life of patients with spinal muscular atrophy. It consists of providing assistance with self-care and mobility, breathing exercises, massages, occupational therapy, physiotherapy, feeding through a gastrostomy with the development of problems with swallowing, respiratory support (including mechanical ventilation) - with the development of respiratory failure.

Complications

Most often spinal amyotrophies complicated by pneumonia, secondary infections and severe respiratory failure.

Prevention of spinal muscular atrophy

Prevention of this pathology does not exist. Perhaps genetic counseling at the stage