Common variable immunodeficiency (CVID) is an immune system disorder in which you have low levels of several of the proteins (antibodies) that help you fight infections. CVID leaves you open to recurrent infections in your ears, sinuses and respiratory system, and increases your risk of digestive disorders, blood disorders and cancer.
Signs and symptoms of common variable immunodeficiency may appear during childhood or adolescence, though many people don't experience them until adulthood. The condition can be inherited, or it can be acquired during your lifetime.
Common variable immunodeficiency care at Mayo Clinic