The DiGeorge syndrome is characterized by absence or hypoplasia of the thymus and parathyroid glands, which leads to a T cell immune deficiency and parathyroid insufficiency.
(See also Overview of immune deficiency disorders, and approach to the patient with an immunodeficiency disorder.)
The DiGeorge syndrome is characterized by absence or hypoplasia of the thymus and parathyroid glands, which leads to a T cell immune deficiency and parathyroid insufficiency. (See also Overview of immune deficiency disorders, and approach to the patient with an immunodeficiency disorder.) DiGeorge syndrome is a primary immunodeficiency disease including T-cell defects. It results from gene deletions in the DiGeorge chromosomal region 22q11, mutations in genes of chromosome 10p13 and other unknown genes, resulting in the eighth week of pregnancy to embryonic malformations of the pharyngeal pouches. Most cases are sporadic and both sexes equally affected. The DiGeorge syndrome is characterized by a partial or complete T-cell defect. Symptoms and complaints The affected infants have low-set ears, median facial clefts, a small, receding chin, hypertelorism, a shortened philtrum, mental retardation and congenital heart disease (eg. As interrupted aortic arch, truncus arteriosus, tetralogy of Fallot, septal defects of the atrium or the ventricle). By absence or hypoplasia of the thymus and parathyroid glands leads to a T cell defect and hypoparathyroidism. Recurrent infections occur soon after birth, but the severity of the immune deficiency varies considerably, so it may be a spontaneous improvement in T cell function. A hypocalcemic tetany occurs within 24-48 hours after birth. The prognosis is often determined by the severity of heart disease. Diagnosis immune function assessment with immunoglobulin (Ig) levels, and Impfstofftitern subset counts of lymphocytes assessment of parathyroid function chromosome analysis The diagnosis of DiGeorge syndrome is based on clinical criteria. If a leukopenia is detected, the absolute number of lymphocytes is determined, followed by the number of B- and T-cells and subsets of lymphocytes; Blood tests to determine the T cells and parathyroid function are performed. Ig levels and Impfstofftiter be measured. When a complete DiGeorge syndrome is suspected, the T-cell receptor Exzisionskreis- (TREC) test should also be conducted. A lateral chest x-ray, the rating of a thymic shadow serve. Using fluorescence in situ hybridization (FISH) assay may chromosomal deletions are shown in the region 22q11; Standard-chromosome tests for the diagnosis of other anomalies can also be performed. When a DiGeorge syndrome is suspected, an echocardiogram is performed. A cardiac catheterization may be necessary when present the patient with cyanosis. Since most cases are sporadic, the screening of relatives is required. Therapy Partial Syndrome: calcium and vitamin D supplement Complete syndrome transplant cultivated thymic tissue or hematopoietic stem cell from partial DiGeorge syndrome parathyroid insufficiency is treated with a calcium and vitamin D substitution; the long-term survival is unaffected. The treatment of complete DiGeorge syndrome is the transplantation of Thymusgewebekulturen or hematopoietic stem cell transplantation. Without treatment, this disease leads to death.