X-linked agammaglobulinemia (Bruton's disease) is a hereditary immunodeficiency disorder due to an abnormality in the X chromosome. It results in few or no B cells (lymphocytes) and very low levels of antibodies (immunoglobulins).

X-linked agammaglobulinemia affects only boys. For about the first 6 months after birth, immunoglobulins from the mother protect against infection. At about age 6 months, levels of these immunoglobulins start to decrease, and affected infants start having recurring infections of the ears, sinuses, and lungs, usually due to bacteria such as pneumococci, streptococci, and Haemophilus bacteria. Some unusual viral infections of the brain may develop. The tonsils are very small, and lymph nodes do not develop.

Blood tests are done to measure immunoglobulin and antibody levels and the number of B cells.

Infusions of immune globulin are given throughout life to provide the missing antibodies and thus help prevent infections. Antibiotics are promptly given to treat bacterial infections and may be given continuously. Despite these measures, chronic sinus and lung infections often develop. With treatment, life span is often unaffected, unless brain infections develop.

Last full review/revision September 2008 by Rebecca H. Buckley, MD