Spinal muscular atrophy is a severe pathology that often makes simple activities such as walking, sitting, inaccessible to the child. The kid may be deprived of even such a natural opportunity as spontaneous breathing. It is very difficult to make predictions for this pathology, after all, there is no special treatment or prevention, and everything depends on the form of the disease and factors, which medicine cannot find an explanation.
What is it?
Speaking of spinal muscular atrophy, they mean not one specific disease, but a whole group of diseases under the general abbreviation SMA. All of them are hereditary and are associated with degeneration of the nerve cells of the spinal cord, which are responsible for motor functions.
Among genetic pathologies in children, spinal muscular atrophies occupy the leading places in terms of frequency of spread. And about one in 6 thousand children is born with such a terrible diagnosis. In 50% of cases, children do not live to be two years old and die. The life of the rest is a disability.
The problem, according to geneticists, is much wider than it might seem according to the above statistics.
The disease develops due to mutation of certain genes, and one of them is SMN1, which is considered the main "culprit" of pathology, in a modified form is recessively present in every fiftieth inhabitant of the planet. This means that healthy parents who do not even know that they are recessive carriers of the mutated gene may well have a baby with spinal muscular atrophy.
The group of diseases was first described in the 19th century by Guido Verding, after whom one of the children's varieties of SMA was later named.
Classification
The most common form of SMA in children is proximal. It is represented by several types of the disease, not all of which become apparent immediately after the birth of the child.
- Werding-Hoffmann disease - SMA type 1, severe infant illness, which manifests itself in the first six months of a child's life. The prognosis with her is the most unfavorable, most patients die. A child with SMA type 1 cannot stand, sit, or roll over on their own. Many newborns have impaired sucking and swallowing reflexes. Often there is no possibility of spontaneous breathing or breathing is difficult.
- Atrophy Dubovitsa - SMA type 2, late infant. It usually appears at the age from six months to one and a half years and later. The child cannot walk, stand, but is able to sit, food is not disturbed, he copes with the task of swallowing and sucking. How long the baby will live depends on the state of the respiratory muscles.
- Kugelberg-Welander atrophy - type 3 SMA, infantile. Usually found at the age of one and a half years, more often at two years. More favorable prognostic form. Little patients can stand, sit, move, but they experience extreme weakness, and therefore in most cases they need a wheelchair, without which normal life is difficult for them.
- Kennedy atrophy - type 4 SMA, bulbospinal. It is usually considered an adult form, but it is rarely detected in children after 15 years. It rarely affects life expectancy, muscle weakening occurs slowly, gradually, a person who led a normal life and considered himself healthy, eventually becomes disabled and loses the ability to move independently.
More or less hearsay Duchenne atrophy and Vulpian's atrophy - SMA "adults", the first is usually detected after 18 years, and the second - after 20 years.
In children, not only isolated forms of SMA are recorded, when, apart from muscle dystrophy, nothing bothers, but also combined forms, when spinal atrophy is not the only diagnosis and the child has other genetic or congenital problems, for example, heart and vascular defects, oligophrenia.
Causes
As already mentioned, we are talking about a genetic disease, and therefore the causes of its occurrence are the area of search for geneticists. The child inherits one of the recessive genes on the fifth chromosome (these can be genes SMN, NAIP, H4F5, BTF2p44).
The carrier has a high probability of passing on such a gene to the offspring - 25%. If both mom and dad are hidden carriers of the mutated gene, then the probability of SMA in a child is 50%. The affected abnormal gene does not allow the SMN protein production to proceed normally, and the nerve cells responsible for the motor functions of the muscles in the spinal cord begin to gradually die. The process of their death continues even after the baby is born.
Manifestations
Symptoms depend on the type of illness. Since we are considering only four types of children, it should be noted that all are characterized by muscle weakness, muscle atrophy. Otherwise, each type has its own clinical picture and distinctive features.
- Type 1 SMA (Werding-Hoffmann atrophy) available for detection even during pregnancy. The doctor can suspect a disease in the fetus with very sluggish movements. But it is difficult to confirm the diagnosis at the stage of bearing a child, this usually happens after childbirth. A kid with such atrophy cannot hold his head himself, toss and turn from side to side, does not sit down. He almost constantly lies on his back, his posture is relaxed, he does not raise his legs, does not bring them together, does not fold the palms of his hands together. At the very early stage, there can be huge problems in order to feed the child, because he is very bad at swallowing or does not succeed. Most of the children die before the age of two. Some manage to live up to seven to eight years, but the atrophy only intensifies. Usually death occurs due to failure of the heart, lungs, digestive organs.
- SMA type 2 (Dubovitsa atrophy) at birth, it is usually not detected, because the child is able to breathe, swallow food, and only after six months the progress of muscle atrophy becomes obvious. If the first symptoms occur at the age when the child has already learned to stand in the crib, then a clear sign may be the limp of the legs, the causeless falling of the crumbs. Gradually it becomes difficult for him to swallow. Over time, the child begins to need a wheelchair.
- Type 3 SMA (Kugelberg-Welander amyotrophy) can show up at any age after 2 years of age. A child who was growing and developing normally gradually begins to complain of weakness, usually in the area of the shoulders and forearms. As he progresses, it becomes difficult for him to run, walk up stairs, and squat. It all depends on the care - some retain the ability to move independently for many years.
- Type 4 SMA (Kennedy atrophy) occurs only in male patients, since it is considered linked to the sex chromosome X. The first signs are weakness in the femoral muscles, the cranial nerves are gradually affected. The disease progresses slowly.
Treatment
Unfortunately, today medical science cannot offer methods and remedies for the treatment of SMA. There are no such methods. To maintain body functions and maximize the period while the child can move on his own, medications such as "Proserin", "Oksazil". They reduce the activity of an enzyme capable of cleaving acetylcholine, which transmits an excitation impulse along the fibers of the nervous system.
Also recommended systematic intake of funds that enhance energy metabolism at the cellular level, B vitamins, nootropics, as well as potassium and nicotinic acid preparations.
A child with SMA shows adherence to a high protein diet, but recent studies have shown that the role of diet is somewhat exaggerated - there is no evidence that high protein content in food in any way affects the rate of progression of the disease.
But with calories, you should be more careful - due to reduced muscle activity, a child can quickly gain extra pounds.
Help to extend the period of more or less full life will help therapeutic massage, UHF, electrophoresis, respiratory gymnastics programs to maintain respiratory muscles, swimming. The wearing of supportive spinal and thoracic orthopedic devices is recommended.
The specialist tells more about the disease in the video below.
