X-linked agammaglobulinemia or Bruton agammaglobulinemia, is an inherited immunodeficiency disease caused by mutations in the gene coding for Bruton tyrosine kinase (BTK). The disease was first elucidated by Bruton in 1952, for whom the gene is named.
X-Linked Agammaglobulinemia (XLA) is an inherited immunodeficiency in which the body is unable to produce the antibodies needed to defend against bacteria and viruses.
A genetic mistake in the BTK gene, prevents B cells from developing normally. B cells are responsible for producing the antibodies that the immune system relies on to fight off infection.
The most common bacteria causing infection in XLA are Streptococcus, Staphylococcus and Haemophilus.
XLA often becomes apparent in infancy once the maternal antibodies wane off, due to recurrent and severe bacterial infections including:
• Ear infections
• Diarrhea due to a parasite called Giardia
Diagnosis of XLA can be made through screening tests that measure immunoglobulin levels or the number of B cells in the blood.
There is no cure for XLA, but the condition can be successfully treated. Immunoglobulin replacement therapy under the watchful monitoring & guidance of an Allergist-Immunologist is a life-long and life-saving treatment that restores some of the missing antibodies. In addition, some people benefit from courses of oral antibiotics to prevent or treat infections.