Muscular spinal atrophy is manifested in early childhood. The first symptoms can occur as early as 2-4 months of age. This is a hereditary disease characterized by the fact that nerve cells gradually die in the brain stem.
Types of problems
Depending on when the first
symptoms of the disease appear, several types of the disease are distinguished from the severity of the course and the nature of the atrophic changes.
Spinal muscle atrophy can develop by:
- the first type: acute (Verdig-Hoffmann form);
- the second type: intermediate (infantile, chronic);
- to the third type: Kugelberg-Velander form (chronic, juvenile).
Three types of the same disease arise, according to experts, due to different mutations of the same gene. Muscular spinal atrophy is an autoimmune disease that occurs when two recessive genes are inherited, one from each parent. The mutation site is located on chromosome 5. It is present in every 40 people. The gene is responsible for encoding a protein that ensures the existence of motor neurons in the spinal cord. If this process is disrupted, then the neurons die.
Verdin-Hoffman disease
You can suspect a problem during pregnancy. If a child develops spinal muscular atrophy of type 1, then a sluggish and late fetal movement during pregnancy is often noted. After birth, doctors can diagnose generalized muscle hypotension.
Atrophies begin to appear in the first months of life. Often in the proximal sections noted fascicular
twitching of the muscles of the back, trunk, limbs. Bulbar disorders are also observed. These include lethargic sucking, a weak cry, a violation of the swallowing process. In children with Verdin-Hoffman's disease, a decrease in vomiting, coughing, pharyngeal, palatine reflexes is often noted. They also note fibrillation of the lingual muscles.
But these are not all the signs by which spinal muscular atrophy can be determined. Symptoms characteristic of type 1 of this disease include weakness of the intercostal muscles. In this case, the chest of the babies looks flattened.
In the first months of life, these children often suffer from respiratory infections, pneumonia, and frequent aspiration.
Diagnosis of Verdin-Hoffman disease
You can determine the disease if you examine the child. There are a number of clinical signs by which specialists can determine that the baby has hereditary spinal muscular atrophy. Diagnostics includes:
- biochemical analysis of blood (a slight increase in aldolase and creatine phosphokinase will be visible in it);
- electromyographic study (the rhythm of the stockade will testify to the defeat of the anterior horns of the spinal cord);
- histological examination of skeletal muscles (clusters of rounded small fibers are detected).
Microscopy of the spinal cord (its front horns) shows that there are degenerative changes in the motor nuclei of the cranial nerves. Spherical swelling and / or wrinkling of motor cells, microglial or astrocytic proliferation, chromatolysis are observed. These phenomena are accompanied by the appearance of dense glial fibers.
It is important to carry out differential diagnostics in order to exclude organic aciduria, congenital or structural myopathies, for example, pemaline, myotubular myopathy or central stem disease.
Prognosis for type I atrophy
Depending on the extent of the lesion, Verdin-Hoffmann disease may begin to manifest itself in the first days after birth. Specialists, even on the position of the child, may suggest that he has spinal muscular atrophy. Photos of these babies are similar: they are in a frog pose. The limbs in the hip and shoulder joints are allotted to them, and in the elbow and knee joints, they are bent.
The proximal located muscles of the lower extremities are the first to suffer. The defeat process is on an ascending line. With the progression of the disease, the muscles of the larynx and pharynx are affected. It happens that the disease appears a little later. But the boundary is the age of 6 months. Children may even begin to lift their heads and roll over, but they never sit down.
Most babies die from heart, respiratory failure or infections in the first year of life. More than 70% of children die before 2 years of age. About 5% of these children survive to 5 years of age.
Atrophy type II
In some cases, other scenarios are possible. Type 2 spinal muscular atrophy appears a little later. Usually the first signs are observed at the age of 8-14 months. For such babies, generalized muscle weakness and hypotension are characteristic.
Thin fingers testify to the disease, a fascicular tremor appears in the muscles of the proximal limbs, in the fingertips. These babies have a period of normal development. They at the right age begin to hold their heads, sit down. But there is no talk of independent walking.
Children can suck and swallow normally; in early infancy, respiratory function is not impaired. But over time, muscle weakness begins to progress. At an older age, swallowing disorders appear, a nasal tone of the voice occurs. One of the most common complications in patients with a significant life expectancy is scoliosis.
Prognosis for atrophy type II
Despite the fact that in the first months the child can develop normally, the situation worsens over time. By the age of two, tendon reflexes of the extremities disappear in children. In parallel, the intercostal muscles weaken. As a result, the chest is flattened, there is a delay in motor development.
Only 25% of children who have been diagnosed with spinal muscular atrophy can themselves sit or stand with support. The late stages of the disease are characterized by the appearance of kyphoscoliosis. Many children die between the ages of 1 and 4 years. The most common causes of death are pneumonia or damage to the respiratory muscles.
When diagnosing spinal muscular atrophy, it is necessary to conduct differential diagnosis with congenital or structural myopathies, an atonic-astatic form of cerebral palsy.
More than 70% of patients live more than two years. The average life expectancy of such children is about 10-12 years.
Kugelberg-Velander disease
The most favorable prognosis is in those patients in whom type III spinal muscular atrophy was diagnosed. It can occur between the ages of a year and 20 years. Most often, the first manifestations are recorded at the age of 2-7 years. The proximal pelvic muscles are the first to suffer.
Patients have difficulty walking, running, squatting, and having to climb stairs. It is worth remembering that the clinical manifestations of this disease in this form are similar to Becker's progressive dystrophy.
The proximal parts of the hands and shoulder girdle are affected only a few years after the first manifestations of the disease. Over time, the chest is deformed, fascicular tremor of the hands and uncontrolled contraction of various muscle groups appear. In this case, tendon reflexes decrease and bone deformities begin to progress. The chest, feet, ankle joints are changing, spinal scoliosis appears.
Prognosis for type III disease
Kugelberg-Velander Disease is an adult spinal muscular atrophy. Over the years, the disease complicates the lives of patients somewhat, but does not lead to severe disability. It progresses quite slowly. Therefore, most people with this diagnosis live to adulthood.
Before starting treatment, it is important to conduct a differential diagnosis with various muscular dystrophies, type 5 glycogenosis and structural myopathies. There is a method with which you can determine spinal atrophy. This is a direct DNA diagnosis. It is necessary, because the clinical manifestations of Kugelberg-Velander disease can vary.
In approximately 50% of cases, patients lose their ability to walk from 12 years old. At the same time, muscle weakness only progresses with age. Hypermobility and contracture of the joints are observed , an increased risk of fractures appears.
Important Signs
As a rule, Verdin-Hoffman disease is diagnosed in the first months of life. If the child does not have movements from birth, then he does not live to even a month old.
Weakness and muscle contractions in infancy, hand tremors and motor retardation should alert both doctors and parents. Such children do not stand up. Only a quarter of all patients can stand with support. Kids are confined to a wheelchair.
But the most difficult to determine Kugelberg-Velander disease. Indeed, in a quarter of patients, muscle hypertrophy is pronounced. Therefore, they can be mistakenly diagnosed with muscular dystrophy, and not spinal muscular atrophy. The causes of this disease were established in 1995, when it was possible to identify the mutating SMN gene. Almost all patients experience a homozygous deletion of SMN7, characterized by the loss of two telomeric copies of this gene and intact centromere copies.
Treatment tactics
Unfortunately, spinal muscular atrophy is an autoimmune disease, the development of which cannot be prevented. Complicating the situation is the fact that there is no specific treatment.
In some cases, doctors can only slightly alleviate the condition of patients with the help of physiotherapy. Improve the quality of their life allows special orthopedic appliances.
Particular attention should be paid to the nutrition of such patients. Often prescribed drugs that can improve metabolism. But this is not all that can be done if spinal muscular atrophy has been confirmed. Treatment consists in the appointment of gymnastics. Physical activity for such patients is important. They are necessary in order to improve the functioning of muscles and increase their mass. True, the load should be calculated by the doctor. In this case, physical education will have a beneficial effect on the whole organism as a whole. Its restorative effect will be apparent. Appointed can be therapeutic or hygienic morning exercises, exercises in water, or just a restorative massage.