Common Variable Immune Deficiency (CVID)
Common Variable Immune Deficiency (CVID) is the most common form of antibody deficiency, usually presenting with recurrent chest and sinus infections in childhood or early adulthood, although most cases are diagnosed in adults. Early recognition can prevent bronchiectasis -permanent damage to the lungs.
CVID affects both males and females. Most people with CVID are not diagnosed until 30 to 40 years of age however around 1 in 5 people with CVID will have symptoms of CVID in childhood, from 2 to 16 years of age. Normal antibody responses are required to fight infections caused by germs such as bacteria, moulds, parasites and viruses. Most people with CVID have recurrent infections due to their reduced antibody responses. These infections usually occur in the ears, sinuses, nose and lungs, which may start in early childhood, adolescence or adult life. Other common infections in CVID include conjunctivitis and persistent diarrhoea. Unusual infections may also occur, including meningitis and blood stream infection. Although people who don’t have CVID can also suffer from these infections, the difference in people with CVID is that the infections are unusually recurrent, prolonged, severe or resistant to normal treatment. When infections are unrecognised or not treated properly in people with CVID, they can result in damage to organs in the body, such as the sinuses, causing chronic sinusitis, or the airways of the lung (bronchi), causing bronchiectasis. This organ damage can lead to tissue damage, causing ongoing mucus secretion and the persistent need to clear phlegm (sputum) or thick white, yellow or green mucus from the nose. Once tissue damage is established, infection tends to become more persistent and difficult to clear.