The human immune system, which protects us from disease, is made up of a complex network of highly specialized cells and organs. When any part of this network is faulty, it interrupts the smooth functioning of the immune response and can result in an immulogic disorder. Chronic granulomatous disease (CGD) is actually a group of rare, inherited disorders of the immune system that are caused by defects in the immune system cells called phagocytes. These defects leave patients vulnerable to severe recurrent bacterial and fungal infections and chronic inflammatory conditions such as gingivitis (swollen inflamed gums), enlarged lymph glands, or tumor-like masses called granulomas. While not malignant, granulomas can cause serious problems by obstructing passage of food through the esophagus, stomach, and intestines as well as blocking urine flow from the kidneys and bladder.

Granuloma (large gray area) in photomicrograph of lung tissue.

How normal phagocytes kill bacteria and fungi

Phagocytes (which means "cell eaters") are the white blood cells (all eaters") are the white blood cells (also called neutrophils) that ciculate in the blood and attack fungal and bacterial invaders. They do so by first engulfing the microbes and then showering them with toxic oxygen compunds such as hydrogen peroxide. This process, called the "respiratory burst" because the phagocyte shows a sudden uptake of oxygen, is triggered whenever normal phagocytes come into contact with bacteria or fungi. The phagocytes of CGD patients are defective, resulting in an inability to kill certain types of bacteria and fungi, leading to the development of serious, often life-threatening, and unusually persistent infections.

In CGD, the granulomas form when white blood cells continue to collect in infected areas even after antibotics have eliminated the infection. This happens because the defective CGD phagocytes cannot generate the oxygen compounds that normally help shut down the body's immune defenses

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