The cat's scream syndrome (sometimes also called Lesian's syndrome) is a rare hereditary disease in which the child has a crying sounding like a cat's meow. The syndrome is considered a chromosomal pathology, because it arises from the lack of a child's piece of genetic information, located in the p-arm of chromosome number 5. This disease is detected in approximately 1 in 45-50 thousand of newborns. The syndrome often develops in girls - in a ratio of about 4k3.
Causes of the cat scream syndrome
The source of a mutation due to which Lesian syndrome arises can be a variety of factors that adversely affect the reproductive organs of the parents or a fertilized egg that is in the process of fragmentation with the subsequent formation of a zygote. Among the main causes of mutation:
Heredity. If there is a child in the family who has this pathology, the probability that the second baby will be born with the same diagnosis is high;
Alcoholic beverages. They are very harmful to the health of the embryo and the germ cells of the mother;
Drugs. They have a destructive effect on the entire genetic apparatus;
Being under the influence of ionizing radiation;
Medicines or chemicals with a powerful effect, which the pregnant woman took on the 1st trimester.
Type of mutation in catcream syndrome
Genetically, this syndrome is explained by partial monosomy. Its occurrence is associated with chromosomal rearrangement, during which it loses from 1/3 to half of the p-arm of chromosome # 5, which contains about 6% of all genetic material. The clinical picture of the disease is affected not only by the magnitude of the missing part, but by what fragment it was lost.
The basis of the syndrome of cat screaming is the changes occurring in the p-arm of chromosome number 5, which usually develop due to division, or, in some cases, due to translocation.
Symptoms of the cat scream syndrome
Among the main symptoms of catnip screaming syndrome are:
Specific sound of crying sick, similar to the cat meowing. This symptom is related to the fact that the larynx has some peculiarities in a sick kid - with thin cartilages, underdeveloped and rather narrow. About a third of all children, this feature disappears until 2 years old, while the rest persists throughout life;
A full-term child has at birth a small weight (less than 2.5 kg);
Problems with swallowing and sucking function;
There is an abundant secretion of saliva;
The face has a lunate, rounded shape (this feature may disappear with age);
Widely planted slanted eyes, their outer corners fall downward, and near the interior there is an epicanthus (a small fold);
The nose is flat, and the nose is wide;
Low ears lowered;
The skull and brain are small in size, there are strongly protruding frontal protrusions. This symptom acquires a sharper outline with age;
Small lower jaw;
Short neck, there are folds of skin on it;
The backwardness in the mental development of the child, physical skills and speech skills also develop with a delay;
Behavior has some features - there are hyperactivity, unmotivated aggression, repetitive motions, hysteria;
Reduced muscle tone of the patient's body;
Heart defects (violation in the structure of partitions (interventricular or interatrial), blue heart disease).
There are several types of mutations that affect the development of the disease:
Short shoulder is completely absent - this is the most frequent variant of the syndrome (and the heaviest). When there is a complete loss of the shoulder, about one-fourth of all genetic information disappears in the chromosome number 5. In addition to the genes themselves, some important parts of the genetic material also disappear, because of which the anomalies that arise in the body become larger and they have a more serious character.
There is a shortening - in this case, only some of the genetic material that is closer to the final section of the chromosome disappears. If this is accompanied by a chromosome rearrangement at the site where the key genes for development are located, Leszmann's syndrome develops. With this variant of defects in the development of the child will be less, because less of the genetic material has disappeared.
Mosaicism is a mild form of the syndrome, which is observed quite rarely. The child receives a DNA from a defect from one of his parents. With this type of mutation, the gene in the zygote was correct at first, chromosome number 5 was full - the disorder occurred already during the development of the fetus. During the separation of chromosomes, the p-arm disappeared without passing the division between the daughter cells. Therefore, some of the cells in the body get an inferior genome. With this form of the syndrome pathological changes will be insignificant, because the division of normal cells to some extent compensates for the defectiveness of the others. Therefore, severe congenital anomalies or any delays in physical development in these children usually does not happen, but here mental abnormalities can still be present.
The ring shape - the two shoulders (short and long) of one chromosome adhere together, which makes the chromosome look like a ring. In this case, chromosome rearrangement takes place in a small terminal area. The syndrome is manifested by any symptoms if the key genes disappear.
Complications and consequences
With Lezgen's syndrome, the patient does not die from the disease itself, but from complications-a kidney or heart failure, various infections.
Diagnostics of the cat scream syndrome
Preliminary diagnosing of the disease can already be done according to the appearance of the kid and his specific crying. To clarify the diagnosis, cytogenetic analysis is performed, as well as a set of chromosomes. A similar examination can be carried out at the parents planning a conception - in those cases if the genus previously had chromosomal diseases.
To diagnose the disease, the newborn takes urine and blood for general, as well as biochemical analysis. Characteristic for the disease in this case will be signs such as a decrease in the blood albumin values, as well as the long-term embryonic hemoglobin.
Methods of instrumental diagnosis of the disease:
Echocardiography, as well as electrocardiography - to detect the presence of heart defects;
The procedure is ultrasound or x-ray to detect abnormalities in the development of the digestive system.
Lesian's syndrome has no specific treatment, only symptomatic therapy of pathologies that result from this disease is performed.
To stimulate the child's psychomotor development, it should be observed in a pediatric neurologist who will conduct massage, drug treatment, exercise therapy and physical therapy courses. In addition, children with this diagnosis need the help of speech therapists, defectologists, and psychologists.
If the baby has heart disease, he often needs correction by surgery, so the patient is referred to a cardiac surgeon who performs the examination, does echocardiography and other necessary procedures.
If a child has a pathology of the urinary system, he is referred to a pediatric nephrologist who assigns to the patient various tests - taking urine and blood for analysis, diagnosing the kidneys through ultrasound, etc.
Prevention of the disease is careful preparation for pregnancy, as well as the exclusion of even before the conception of the possible impact on the body of future parents of any negative factors. If a child is born with Lejeune's syndrome, his parents are required to undergo a cytogenetic examination procedure in order to be tested for the carriage of a balanced chromosomal rearrangement.
The cat's scream syndrome has an unfavorable long-term prognosis. The quality of life, as well as its duration in this syndrome, depends on the type of mutation, the severity of the associated congenital pathologies, and the level of psychological, pedagogical and medical care provided. Children who have completed special education have a vocabulary that allows them to communicate at a household level, but physical and psychological development often remains within the preschool age.
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