what is the treatment for this disorder? Is there a permanent cure?
From Vincent Iannelli, M.D.,
Your Guide to Pediatrics.
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Hyper-IgM is a rare immunodeficiency disease in which the immune system fails to produce IgA and IgG antibodies.
What causes hyper-IgM syndrome?
A flawed gene (or genes) in T cells is responsible for hyper-IgM syndrome. The faulty T cells do not give B cells a signal they need to switch from making IgM to making IgA and IgG. Most cases of hyper-IgM syndrome are linked to the X chromosome. Because boys carry only one X chromosome, unlike girls whose second X chromosome helps to protect against the disease, more boys than girls have IgM syndrome.
What are the symptoms of hyper-IgM syndrome?
Infants usually develop recurring upper and lower respiratory infections within the first year of life. Other signs of the disease include enlarged tonsils, liver, and spleen, chronic diarrhea, and an increased risk of unusual or opportunistic infections and non-Hodgkin's lymphoma.
How is hyper-IgM syndrome diagnosed?
The doctor will order laboratory tests that show normal numbers of T and B cells, but high levels of IgM and very low IgG and IgA. Patients also may have neutropenia, a low number of white blood cells. The doctor may ask whether the family recalls other relatives who had immune system problems in infancy.
How is hyper-IgM syndrome treated?
Patients receive injections of intravenous immunoglobulin (IVIG) every three or four weeks. For neutropenia, patients can take G-CSF, a protein that stimulates the body to produce more granulocytes. Their doctor may also prescribe antibiotics to prevent the lung disease, Pneumocystis carinii pneumonia.
In a mouse model of this PI, scientists have restored the animal's ability to make antibodies and improved their survival by giving them artificial CD40 ligand, a molecule that allows T cells to communicate with B cells. A study to determine whether this treatment will be effective in humans is underway.