Definition of Chronic granulomatous disease:

Chronic granulomatous disease is an inherited disorder in which immune system cells called phagocytes do not function properly. This leads to ongoing and severe infection.

Causes, incidence, and risk factors:

Chronic granulomatous disease (CGD) is a genetic disorder in which certain immune system cells are unable to kill some types of bacteria and fungi. The disorder leads to long term (chronic) and repeated (recurrent) infections. The condition is often discovered in very early childhood. Milder forms may be diagnosed during the teen years or even in adulthood.

Impetigo, skin abscesses and furuncles, and perianal and rectal abscesses are common in people with this disorder. Pneumonia that keeps coming back, and is caused by bacteria not typical of most pneumonias, is a significant problem. Chronic swelling of the lymph nodes in the neck, with the formation of abscesses, is common.

Risk factors include a family history of recurrent or chronic infections.

About half of CGD cases are transmitted as a recessive, sex-linked trait. This means that boys are more likely to inherit the disorder than are girls. Boys have an X and a Y chromosome. Girls have two X chromosomes. The defective gene is carried on the X chromosome. So, if a girl has one X chromosome with the defective gene, the other X chromosome may have a working gene to make up for it. A girl has to inherit the defective gene from both parents in order to have the disease.

About 1 in a million people have CGD.