Trisomy 22 is a hereditary disease in which chromosome 22 is present three times. The disease causes both cognitive and physical disabilities. Those affected can suffer from the restrictions to varying degrees.
What is trisomy 22?
Trisomy 22 is a genetic disease that leads to mental and physical impairments. Disability can vary in severity. A trisomy is caused by an error in cell division. Normally, human cells have a double (diploid) set of chromosomes, in which every single chromosome is present twice. In the case of a trisomy, however, the affected chromosome appears three times in the genome. For ketoacidosis definition and meaning, please visit eshaoxing.info.
Medicine differentiates between different sub-forms of trisomy 22:
- In free trisomy 22, all body cells have three 22nd chromosomes that are independent and clearly separated from each other.
- In the case of translocation trisomy 22, the extra chromosome shifts and joins with another. At first glance, the chromosome set therefore appears to have the correct number of chromosomes.
- In partial trisomy 22, only one section of a chromosome is duplicated. Accordingly, this part (Latin “pars”) is present three times. Visually, partial trisomy is characterized by the fact that one of the affected chromosomes is longer: it carries the extra part.
- In contrast, people with mosaic trisomy have both trisome cells and disome cells; the trisomy is limited to just one cell line. Most of those affected have such a mosaic trisomy, since the probability of survival with this type is significantly higher than with other forms.
Causes
Trisomy 22 is caused by an error in cell division. Normally, when a cell divides, one chromosome of each type migrates into one of the two halves of the cell. Immediately after division, the new cells therefore have a simple (haploid) set of chromosomes. Only then does the cell copy the genetic information so that two chromosomes of each type are present again. However, errors can occur in this process.
If the chromosomes do not divide correctly between the two halves of the cell, one of them has one chromosome too many. Despite this, the cell makes a copy of one of the chromosomes; the finished cell therefore contains three chromosomes 22 instead of just two. Cell division errors of this kind can occur in both men and women. The cause of trisomy 22 in the child can therefore lie equally with the father or the mother.
Symptoms, Ailments & Signs
The symptoms of trisomy 22 include both mental and physical impairments. The psychological symptoms primarily include cognitive limitations. For example, those affected may have a lower intelligence quotient (IQ). Cognitive impairments therefore show up in different areas of thinking.
In the case of trisomy 22, especially the mosaic type, it is very important how much the brain cells are affected by the trisomy. A heart defect manifests itself in about 50 percent of the affected children. This is a malformation of the organ: The anatomical shape of the heart or its blood vessels has special features. They lead to the heart not working properly or tiring prematurely.
Doctors therefore recommend regular monitoring even for heart defects that do not pose an acute risk. Heart defects in trisomy 22 are just one of the possible organ damage. In the case of mosaic trisomy 22, it depends on which cells of the organism are affected by the trisomy – the type and extent of the organic malformations also depend on this.
Diagnosis & course of disease
External physical characteristics can provide the first signs of trisomy 22. The affected children often have a strikingly broad skull and a high forehead. The face is often flat with wide-set eyes, low-set ears and a beaked nose. The lower jaw typically protrudes. A genetic test can unequivocally identify trisomy 22.
Complications
Trisomy 22 leads to many different limitations and symptoms. As a rule, those affected suffer from a number of different cognitive and motor disorders that cannot be treated directly. Mental retardation also occurs, so that the patients are dependent on the help of other people in their lives.
However, trisomy 22 can also promote a heart defect, so that those affected can die of sudden cardiac death. The heart itself cannot work properly due to the malformation, so that the patients quickly appear tired and exhausted. For this reason, you are dependent on regular examinations to avoid further complications.
However, other organs can also be damaged by trisomy 22. The disease can also lead to aesthetic problems. The patients often do not feel beautiful and suffer from reduced self-confidence or, in childhood, from bullying or teasing.
Since a causal therapy of trisomy 22 is not possible, only the individual complaints and symptoms of the disease can be alleviated. There are no complications. Relatives and parents are often affected by the psychological symptoms of the disease and therefore also need treatment.
When should you go to the doctor?
In the case of trisomy 22, the person affected is dependent on medical examination and treatment so that further complications can be prevented. In the worst case, if left untreated, this disease can lead to the death of the affected person, so that early diagnosis with subsequent treatment always has a very positive effect on the further course of trisomy 22. Since it is also a genetic disease, genetic counseling should also be carried out if you wish to have children.
A doctor should be contacted if the person concerned suffers from significantly reduced intelligence. Heart problems or malformations all over the body can also indicate this disease and should be examined by a doctor. Rapid tiredness or permanent exhaustion can also indicate this disease.
As a rule, trisomy 22 is diagnosed by a pediatrician or a general practitioner. Further treatment depends on the exact symptoms and is carried out by a specialist. In some cases, the life expectancy of those affected is also reduced by this disease. It is not uncommon for parents and relatives to need psychological treatment.
Treatment & Therapy
Like all trisomies, trisomy 22 cannot be cured. The affected cells have three 22nd chromosomes from birth and cannot lose the extra chromosome. The treatment is therefore primarily directed against the damage that occurs as a result of the mutation. The treatment can therefore look very different in individual cases.
Since heart defects are particularly common, medical therapy often focuses on this vital organ. Physiotherapy and occupational therapy usually support the treatment of physical disabilities. If children with trisomy 22 show severe behavioral problems, psychotherapeutic approaches can also be considered. They can also be useful when those affected suffer greatly from the social or emotional consequences of the disability.
Prevention
Anticipatory family planning is beneficial to prevent trisomy 22 and similar diseases. The probability of such mutations increases the older the child’s mother is. Doctors consider a mother’s age of less than 35 years to be relatively uncritical. In this age range, the risk of trisomy is significantly lower.
Nevertheless, these are only probabilities: Even if the mother is young, there is no guarantee that a trisomy or other genetic defects can be completely ruled out. In mothers over 35, prenatal diagnosis may be useful, since children with trisomy 22 are often not born alive. Older fathers also increase the risk of trisomy in the child.
Aftercare
Since the clinical picture of trisomy 22 is very different, individually tailored aftercare is also required. The follow-up measures are about observing the peculiarities associated with the chromosomal disorder and, if necessary, initiating treatment of problems if they can be reduced in this way. Patients, who are in most cases cognitively impaired, benefit from lifelong support measures that are initiated at an early stage.
Restrictions in the musculoskeletal system and motor skills can be improved as part of the aftercare with physiotherapy or occupational therapy. The heart defects that occur in about every second person affected require close monitoring even after the actual treatment. In this way, deterioration can be detected at an early stage and the treating cardiologist can take appropriate measures if necessary.
Follow-up care also includes caring for family members. The parents of children with trisomy 22 must be supported in such a way that they can take care of the child in the best possible way. If necessary, psychological help can be useful. After a woman has given birth to a child with trisomy 22, human genetics can be used to determine whether there is an increased risk of recurrence.
During a subsequent pregnancy, prenatal diagnostics can provide information as to whether the child is affected again. However, the risks of invasive diagnostic measures should not be ignored.
You can do that yourself
Trisomy 22 from the group of hereditary diseases cannot be cured, but there are self-help and support options with which the quality of life can be sustainably increased.
Due to the heart defect, it is important to pay attention to a healthy diet. In particular, avoiding overeating and high-cholesterol foods has a positive effect. Excessive sport must not be driven, but easy running in the fresh air is recommended. A regular check-up of the heart must be carried out by a specialist several times a year. Ergotherapy and physiotherapy for the treatment of motor impairments can help, in particular it serves to maintain existing skills and abilities. Specially trained motologists help to experience the body’s own limits and build a positive relationship with it.
Psychotherapeutic treatment is indicated to accompany and support you in everyday life. Emotional and social stress factors are identified and resolved in a protected environment. Talking and behavioral psychotherapy is particularly suitable for this purpose. Systemic psychotherapy has a positive effect on problems affecting the social and family environment. A broad social environment with various contact points has a positive effect. Self-help groups offer a place where experiences can be exchanged and further information and help options are offered.
