X-Linked Agammaglobulinemia

One out of 100,000 people have XLA. Genetic alterations on the X chromosome cause XLA. Boys get XLA if they inherit an X chromosome that contains the alteration. Girls, on the other hand, are protected by having two sets of X chromosomes because one healthy chromosome can override the malfunctioning one.

XLA is also called

• Bruton type agammaglobulinemia
• X-linked infantile agammaglobulinemia
• congenital agammaglobulinemia

What causes XLA?

Mutations in a gene found on the X chromosome cause XLA. This gene normally produces a protein that B cells need to mature.

What are the signs and symptoms of XLA?

Infants with XLA develop frequent pus-producing infections of the inner ear, lungs, and sinuses. Serious infections can develop in the bloodstream and internal organs. They tend to cope well with most short-term viral infections, but are very susceptible to chronic viral infections such as hepatitis, polio, and ECHO viruses.

They may fail to grow to normal height or to gain weight. Their tonsils and adenoids are often missing.

How is XLA diagnosed?

Patients with XLA have extremely low levels of mature B cells. Blood tests also show overall immunoglobulin levels to be low. They don't develop antibodies to specific germs (as seen after immunizations, for instance).

How is XLA treated

For the rest of their lives, people with XLA must have their antibodies replaced through monthly injections of intravenous immunoglobulin (IVIG).

For More Information:

• Primary Immunodeficiency

^{reproduced from the National Institute of Allergy and Infectious Diseases Fact Sheet on Primary Immune Deficiency}