Hypogammaglobulinemia (HI-po-GAM-uh-GLOB-you-luh-NEE-mee-uh) is an abnormally low level of immunoglobulins (antibodies also called proteins that help fight infections) in the blood.

More to Know

The body's immune system uses white blood cells, or leukocytes, to seek out and destroy disease-causing organisms or substances. Lymphocytes are a type of white blood cell, and the two types of lymphocytes are B lymphocytes and T lymphocytes.

B lymphocytes produce antibodies (immunoglobulins) that target foreign substances for destruction. When someone has hypogammaglobulinemia, his or her body is lacking in B lymphocytes. This leads to low levels of immunoglobulins, making the person more likely to be infected by a bacteria or virus.

Doctors don't always know what causes hypogammaglobulinemia, but it can be present at birth (congenital) or develop later in life (acquired). People with hypogammaglobulinemia typically have a lot of respiratory problems, sinus and ear infections, and gastrointestinal disorders. They also face a greater risk of more serious infections.

Keep in Mind

Most children born with transient hypogammaglobulinemia of infancy will grow out of it between the ages of 2 and 5. Other types of hypogammaglobulinemia are lifelong conditions. The risk of infection can be reduced by different treatments, depending on the type and cause of hypogammaglobulinemia. One of the more common treatments is an intravenous (IV) form of replacement immunoglobulins.

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