X-linked agammaglobulinemia

X-linked agammaglobulinemia (XLA) is a condition that affects the immune system and occurs almost exclusively in males. It is part of a group of disorders called primary immunodeficiencies (or inborn errors of immunity), in which part of the immune system does not function as it should. People with XLA have very few B cells, which are specialized white blood cells that help protect the body against infection. B cells can mature into the cells that produce special proteins called antibodies or immunoglobulins. Antibodies attach to specific foreign particles and germs, marking them for destruction. Individuals with XLA are more susceptible to infections because their body makes very few antibodies.

Children with XLA are usually healthy for the first 1 or 2 months of life because they are protected by antibodies acquired before birth from their mother. After this time, the maternal antibodies are cleared from the body, and the affected child begins to develop recurrent infections. .cf0{font-style:italic;font-family:Segoe UI;font-size:9pt;}Children with XLA generally take longer to recover from infections, and infections often occur again, even in children who are taking antibiotic medications.

The most common bacterial infections that occur in people with XLA are lung infections (pneumonia and bronchitis), ear infections (otitis), pink eye (conjunctivitis), and sinus infections (sinusitis). Infections that cause chronic diarrhea are also common. Recurrent infections can lead to organ damage. .cf0{font-style:italic;font-family:Segoe UI;font-size:9pt;}Treatments that replace antibodies can help prevent infections, improving the quality of life for people with XLA.