Primary immunodeficiency diseases (PID) are a group of disorders in which the patient has a defective or absent part of the immune system, which makes him susceptible to infections by different infectious agents. These infections happen repeatedly and can affect the skin, respiratory, gastrointestinal system or any other organ system. They are often severe and unusually difficult to treat.
By primary, we mean that these diseases are not secondary to another disorder. Most of the cases are genetics. The patient is usually born with the defect that results in the abnormal function of the immune system.
There are more than 250 different diseases. We will talk briefly about each one of them.
