D80: Immunodeficiency with predominantly antibody defects

D80.4: Selective deficiency of immunoglobulin M [IgM]

The immune system protects the body from pathogens and foreign substances. The immune system can also destroy cells in the body that have pathologically changed. The body's immune system is made up of different types of immune cells. Some immune cells can destroy pathogens or foreign bodies themselves. Other immune cells produce certain antibodies. Some of the immune system’s antibodies can make pathogens and foreign substances visible to the immune system. Other antibodies attack pathogens or foreign substances directly.

There are various antibody groups. Your immune system is not producing enough antibodies in one group. In the early phase, immediately after becoming infected, these antibodies are important in protecting against pathogens.

If you are not producing enough of these antibodies, you may be unable to properly combat various pathogens. Most people affected suffer few or no problems as a result. However, the pathogens may also repeatedly cause infection. The infections can affect the respiratory tract or the skin, for example. The infections may also be more severe and last longer than normal.

As yet there has not been enough research into why some people are deficient in certain antibodies.