What is Common Variable Immune Deficiency (CVID)?

Common Variable Immune Deficiency (abbreviated as CVID) is a rare, congenital immune disorder, affecting about 1 in 25,000 people.

Background of defense disorders and CVID

Immune disorders are (congenital) diseases that are the result of a disorder in the development or function of the human immune system. The human immune system consists of various (white blood) cells and proteins and ensures that infections caused by bacteria, viruses, fungi and parasites are cleaned up. The different (white blood) cells each have their own function in the defense.


One of those white blood cells is the B lymphocyte. The B-lymphocyte makes antibodies (or immunoglobulins), which attach to bacteria as they enter our body and ultimately ensure that bacteria are cleaned up.

In CVID there is a disorder in the development of the B-lymphocytes, leading to too low amounts of antibodies in the bloodstream, resulting in a higher risk of serious and recurrent infections, for example from the airways (lungs, nose and jaw sinus, ears).  and the gastrointestinal system. Repeated infections can lead to damage to organs, for example lungs, which may cause lung capacity and lung function to deteriorate.

CVID: not just infections

Although there is a shortage of antibodies in patients with CVID, some of these antibodies (autoantibodies) can attack cells or tissues of the body. Patients with CVID therefore have a higher risk of autoimmune diseases, such as breakdown of red blood cells (leading to anemia) and platelets (resulting in an increased risk of major bleeding). Auto antibodies can also target tissues and organs, such as joints and cause joint inflammations, as we also see in patients with joint rheumatism.

Patients with CVID have an increased risk of developing a malignant gastrointestinal disorder or starting from blood cells from the bone marrow due to their disease.


In recent years, several genetic abnormalities have been found in the DNA that can lead to CVID, but in most patients with CVID no known genetic defect has yet been demonstrated. The exact causes of CVID therefore often remain unknown. In addition, CVID is a condition that is different in every patient and leads to other complications (more infections or more autoimmunity). The origination mechanism of CVID therefore seems very complex.

Explanation of antibody shortages

For a short video about the immune system and antibody shortages see the video below:


Immune disorders

It is the most common of the serious antibody deficiencies and both children and adults, and both men and women can be affected by this disease.