Chronic granulomatous disease

- rare immunodeficiency due to a defect in neutrophil killing and characterised by deep seated infection
- defect in production of NADPH-oxidase found in phagocytes
- patients with CGD have defective phagocytes that are able to engulf bacteria, but once engulf unable to kill them, leads to granuloma and microabscesses in skin, liver and bone
- nitroblue tetrazolium test is a simple screening test of reducing power of phagocytes