DiGeorge Syndrome affects the production of lymphocytes and can cause various autoimmune diseases, among other things. It is a genetic and congenital condition that can affect 1 in every 4,000 births, and is sometimes detected until adulthood.
Next We will see what DiGeorge syndrome is and what are some of its consequences and main manifestations.
DiGeorge Syndrome is an immunodeficiency disease caused by an excessive growth of certain cells and tissues during embryonic development It generally affects the thymus gland, and with this, and the production of T lymphocytes, which results in the frequent development of infections.
Causes
One of the main characteristics that 90% of people diagnosed with this syndrome have is that a small part of chromosome 22 is missing (from position 22q11.2, specifically). For this reason, Digeorge Syndrome is also known as chromosome 22q11.2 deletion syndrome
Likewise and due to its signs and symptoms, it is also known as Velocardiofacial Syndrome or Abnormal Conotruncal Face Syndrome. Deletion of a fraction of chromosome 22 may be caused by random events involving sperm or eggs, and in few cases due to hereditary factors. So far what is known is that the causes are non-specific.
Symptoms and main characteristics
The manifestations of DiGeorge Syndrome can vary according to the organism itself. For example, there are people who have severe heart conditions or some type of intellectual disability and even special susceptibility to psychopathological symptoms, and there are people who do not have any of this.
This symptomatic variability is known as phenotypic variability, since it depends largely on the genetic load of each person. In fact, this syndrome is considered a clinical condition with high phenotypic variability. Some of the most common features are as follows.
1. Characteristic facial appearance
Although this does not necessarily occur in all people, some of the facial characteristics of Digeorge Syndrome include a very developed chin, heavy-lidded eyes, and ears turned slightly back with part of the upper lobes over them. There may also be a cleft palate or poor palate function
2. Cardiac pathologies
It is common for different alterations of the heart to develop, and therefore of its activity. Generally these alterations affect the aorta (the most important blood vessel) and the specific part of the heart where it develops. Sometimes these alterations may be very slight or may be absent.
3. Alterations in the thymus gland
In order to act as a protector against pathogens, the lymphatic system must produce T cells. In this process, the thymus gland plays a very important role This gland begins its development in the first three months of fetal growth, and the size it reaches directly affects the number of T-type lymphocytes that develop. People who have a small thymus produce fewer lymphocytes.
While lymphocytes are essential for protection against viruses and for producing antibodies, people with DiGeorge Syndrome have a significant susceptibility to viral, fungal and bacterial infections. In some patients, the thymus gland may even be absent, requiring immediate medical attention.
4. Development of autoimmune diseases
Another consequence of the lack of T lymphocytes is that some autoimmune disease can develop which is when the immune system (antibodies) tends to act inappropriately towards the body itself.
Some of the autoimmune diseases caused by DiGeorge Syndrome are idiopathic thrombocytopenic purpura (which attacks platelets), autoimmune hemolytic anemia (against red blood cells), rheumatoid arthritis or autoimmune thyroid disease.
5. Alterations in the parathyroid gland
DiGeorge syndrome too can affect the development of a gland called the parathyroid (located in the front of the neck, near the thyroid). This can cause changes in metabolism and alterations in calcium levels in the blood, which can lead to seizures. However, this effect usually becomes less severe as time passes.
Treatment
The recommended therapy for people who have DiGeorge Syndrome is directed toward correcting changes in organs and tissues. However, and due to the high phenotypic variability, The therapeutic indications may be different depending on the manifestations of each person
For example, to treat disorders of the parathyroid gland, calcium compensation treatment is recommended, and for cardiac disorders there is specific medication or, in some cases, surgical intervention is recommended. It can also happen that T lymphocytes function normally, therefore, no therapy is required for immunodeficiency. Likewise, it may occur that the production of T lymphocytes gradually increases with age.
Otherwise, specific immunological care is needed, which includes constantly monitoring the immune system and the production of T lymphocytes. For this reason, it is recommended that if a person has recurrent infections without an apparent cause, tests are performed to evaluate the entire system. Finally, in the event that the person completely lacks T cells (what can be called “Complete DiGeorge Syndrome”), a thymus transplant is recommended.
