DiGeorge syndrome is a congenital immunodeficiency disorder in which the thymus gland is absent or underdeveloped at birth.
Usually, DiGeorge syndrome is due to a chromosomal abnormality, but it does not usually run in families. Boys and girls are equally affected. The fetus does not develop normally, and abnormalities often occur in the following:
The prognosis usually depends on the severity of the heart disorder.
Doctors suspect the diagnosis based on symptoms. Blood tests are done to determine the total number of blood cells and the number of T and B cells and to evaluate how well T cells and the parathyroid glands are functioning. Blood tests are also done to determine how well the body produces immunoglobulins in response to vaccines.
A chest x-ray may be taken to check the size of the thymus gland. Chromosomal tests may be done to look for abnormalities.
For children who have some T cells, the immune system may function adequately without treatment. Infections that develop are treated promptly. Calcium and vitamin D supplements are given by mouth to prevent muscle spasms.
For children who have very few or no T cells, the disorder is fatal unless transplantation of thymus tissue is done. Such transplantation can cure the immunodeficiency. Before the thymus tissue is transplanted, it is placed in a culture dish and treated to eliminate mature T cells. These cells may identify the recipient's tissue as foreign and attack it, causing graft-versus-host disease (see Graft-versus-host disease). Stem cell transplantation may also be done.
Sometimes the heart disease is worse than the immunodeficiency, and surgery to prevent severe heart failure or death may be needed.
Last full review/revision February 2014 by James Fernandez, MD, PhD