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X-linked Agammaglobulinemia

(Bruton Disease)


James Fernandez

, MD, PhD, Cleveland Clinic Lerner College of Medicine at Case Western Reserve University

Reviewed/Revised Jan 2023
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X-linked agammaglobulinemia is characterized by low levels or absence of immunoglobulins and absence of B cells, leading to recurrent infections with encapsulated bacteria.

As a result, male infants have very small tonsils and do not develop lymph nodes; they have recurrent pyogenic lung, sinus, and skin infections with encapsulated bacteria (eg, Streptococcus pneumoniae, Haemophilus influenzae). Patients are also susceptible to persistent central nervous system (CNS) infections resulting from live-attenuated oral polio vaccine and from echoviruses and coxsackieviruses; these infections can also manifest as progressive dermatomyositis Autoimmune Myositis Autoimmune myositis is characterized by inflammatory and degenerative changes in the muscles (polymyositis, necrotizing immune-mediated myopathy) or in the skin and muscles (dermatomyositis)... read more Autoimmune Myositis with or without encephalitis. Risk of infectious arthritis Acute Infectious Arthritis Acute infectious (septic) arthritis is a joint infection that evolves over hours or days. The infection resides in synovial or periarticular tissues and is usually bacterial—in younger adults... read more Acute Infectious Arthritis , bronchiectasis Bronchiectasis Bronchiectasis is dilation and destruction of larger bronchi caused by chronic infection and inflammation. Common causes are cystic fibrosis, immune defects, and recurrent infections, though... read more Bronchiectasis , and certain cancers is also increased.

With early diagnosis and appropriate treatment, prognosis is good unless viral infections of the central nervous system develop.

Diagnosis of X-linked Agammaglobulinemia

  • Low immunoglobulin levels and absent B cells

  • Genetic testing

Diagnosis of X-linked agammaglobulinemia is by detecting low (at least 2 standard deviations below the mean) levels of immunoglobulins (IgG, IgA, IgM) and absent B cells (< 1% of all lymphocytes are CD19+ cells, detected by flow cytometry). Transient neutropenia may also be present.

Treatment of X-linked Agammaglobulinemia

  • Immune globulin replacement therapy

Prompt use of adequate antibiotics for each infection is crucial; bronchiectasis may require frequent rotation of antibiotics. Live-virus vaccines are contraindicated.

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