Primary Immunodeficiency (PI) : Treatments, Part 6

by National Institute of Health

(Page 10 of 13)

Children with AT gradually lose more and more control of their muscles, and they may develop writhing and jerking movements. By the time they are in their teens, many are confined to a wheel chair. Their infections multiply, too. In addition, they are liable to develop cancers, especially cancers related to immune system cells and organs.

However, the symptoms and severity of AT differ greatly from one child to another, and the disease develops at a different rate for each one. Some have lived well into adulthood, attending college and living independently.

Medical researchers have tried a number of new approaches, including transplants of thymus tissue and BMT. To date, however, nothing has succeeded in halting the disease's advance.

Treatment is geared to helping the children maintain as normal a lifestyle as possible. They are encouraged to attend school and participate in a wide variety of activities. Physical therapy helps the children remain mobile and active.

Infections, of course, need to be treated promptly. AT in children with an IgG deficiency may benefit from IVIG.

T Cell Deficiencies

DiGeorge Anomaly is the result of a birth defect. In the growing fetus, a group of cells that give rise to various parts of the head and neck develops abnormally. Developmental changes can affect the face, parts of the brain, and the heart, as well as the thymus, where T cells mature.

The symptoms of DiGeorge Anomaly may be different for each child, depending on which organs are abnormally affected. The abnormalities can range from mild to severe.

Some children with DiGeorge Anomaly have a distinctive look, with an underdeveloped chin, eyes that slant downward, and misshapen ear lobes. Some children also have underdeveloped parathyroid glands. The parathyroids, located in the neck next to the thyroid gland, produce a hormone that helps to control levels of calcium in the blood; when calcium levels are not balanced, the child can develop convulsions. Children with DiGeorge Anomaly may also have a variety of heart defects, which causes symptoms ranging from a heart murmur to heart failure.

Many children with DiGeorge Anomaly have a very small thymus that is normal. In others, the thymus is missing altogether. With too few T cells, or T cells that are not functioning properly (which means B cells dependent on T cells aren't functioning, either), the child falls prey to infection.

Because of the unusual mixture of characteristic features, DiGeorge Anomaly is usually diagnosed soon after birth. Laboratory analysis of the chromosomal defects in the child's blood cells can be used to confirm the diagnosis.

Treatments are geared to correcting the various defects. The heart malformation, which is usually the most serious problem, requires drugs and often surgery. The child may be given IVIG to prevent infections and drugs to defend against Pneumocystis pneumonia. Other treatments include calcium supplements and parathyroid hormone.

For many children with DiGeorge Anomaly, a tiny thymus will eventually grow big enough to produce enough T cells to stave off infection. About a quarter of all children, though, will require some sort of treatment, and researchers are working to find what works best.

An experimental approach is an identically matched BMT which contains T cells that are mature and thus work independently of a thymus. Another experimental technique being used is the transplantation of fetal thymus tissue.

Cartilage Hair Hypoplasia is an immune system abnormality linked to dwarfism. The child has abnormally short limbs and thin, sparse hair. The skin forms extra folds around the neck, hands, and feet, and the joints are loose.

Youngsters with Cartilage Hair Hypoplasia can get frequent infections of the skin and mouth, the result of too few T cells. Their biggest danger is chicken pox which can be deadly.

The prognosis is considerably better than most T cell immunodeficiencies, because the susceptibility to infection is less. Although some children succumb to overwhelming infections in infancy, most get relatively few infections and some live normal lives. Some children have been successfully treated with BMT.

About the Author

NIH is the nation's medical research agency - making important medical discoveries that improve health and save lives. The National Institutes of Health (NIH), a part of the U.S. Department of Health and Human Services, is the primary Federal agency for conducting and supporting medical research.