D84: Other immunodeficiencies

D84.1: Defects in the complement system

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. Certain proteins in the blood also form part of the immune system. These proteins are important in protecting against pathogens.

Depending on which protein is affected, different illnesses can occur. Depending on the illness, the symptoms can vary widely. For example, with certain illnesses, repeated swellings may occur. With other illnesses, pathogens may cause problems more frequently. Such pathogens include certain bacteria, for example.