X-linked Agammaglobulinemia

What is X-linked Agammaglobulinemia?

X-linked agammaglobulinemia is a genetic condition that causes problems with a person’s immune system. This condition affects males almost exclusively. X-linked agammaglobulinemia is also sometimes referred to as Bruton’s agammaglobulinemia. When a person suffers from this genetic disorder, they have very few B cells in the body. B cells are specialized white blood cells. Their function in the body is to help protect the body from possible infections. B cells also mature and produce immunoglobulins and antibodies that are necessary to fight off infections.

When a person has X-linked agammaglobulinemia, they are much more prone to infections and are very likely to develop severe infections when other people may develop only minor ones.  The cause of X-linked agammaglobulinemia is a mutation to the BTK gene. The BTK gene is responsible for providing the body with instructions to create what is known as the BTK protein, which in turn is vital to the development of B lymphocytes (B cells).

X-linked agammaglobulinemia is associated with the X chromosome and due to the fact that males only have one X chromosome, they only need one mutated copy of the BTK gene to cause the condition (which is why it is so much more likely to affect men than women). It follows what is known as an autosomal recessive inheritance pattern.

What are the Symptoms of X-linked Agammaglobulinemia?

Suffering from recurrent and prolonged infections is the most common symptom of X-linked agammaglobulinemia.

The infections most commonly associated with this genetic condition include lung infections such as chronic bronchitis and pneumonia (primarily bacterial pneumonia). Sinusitis (sinus infections) are also very common for men who have X-linked agammaglobulinemia.

Other chronic or recurrent infections can include otitis (ear infections), conjunctivitis (pink eye), and chronic diarrhea due to various bacterial and parasitic infections. These infections generally first occur during infancy leading to a diagnosis, but sometimes, it can take longer to determine the cause of chronic infections.

X-Linked Agammaglobulinemia Causes

X-Linked Agammaglobulinemia, also called XLA, is a rare genetic disorder that causes sufferers – almost exclusively men – to have fewer B cells, which are specialized white blood cells to be less effective at fighting infections.

The exact cause of XLA is unknown, but the result is a genetic mistake that causes B cells to develop abnormally. As a result, several infections such as streptococcus, staphylococcus, and haemophilus can appear.

Children that have XLA are normally healthy for the about the first month after their birth. This is thought to be caused by the presence of maternal antibodies that are still present in the child’s system for that period of time. After that time, however, the XLA can become active, making the child’s body susceptible to the mutation, and as a result the related infections and other problems.

How is X-linked Agammaglobulinemia Treated?

X-linked agammaglobulinemia is not curable. There are, however, treatments that can help a person to manage it.

Treatments include antibiotics will help to treat bacterial infections that can occur. Sometimes, these antibiotics are given as a preventive measure (prophylactically) if a person has been exposed to infection (such as having a family member or spouse with a contagious infection) or even on a daily basis. Immunoglobulins can also be injected into the vein as well. This can help boost the immune system and protect a person with X-linked agammaglobulinemia from developing infections and reducing the severity of infections when they do occur.

X-Linked Agammaglobulinemia Prevention

At the present time, there are no preventive measures that can be taken for XLA. Even for children who might be susceptible to the mutation, there is no test to determine whether XLA will be a problem in the future.

XLA is a condition that needs to be closely monitored, however, once it is discovered. This is because once it has been identified, the problems it can cause can create serious difficulties. This includes not only infections as a primary issue, but ultimately problems such as organ damage and eventually death.

Once infections come about, they need to be treated aggressively. Treatments usually consist of antibiotics that are given for longer periods of time than are normal with otherwise healthy people. This ensures that treatment is effective and prevents the chances of common complications such as chronic sinusitis and lung disease.

Last Reviewed:
October 11, 2016
Last Updated:
September 08, 2017