Chronic granulomatous disease is due to deficiency of

(Oxydase): (153- Baveja 4th Microbiology)Chronic Granulomatous disease (CGD) is fatal genetic disorder, deficiency of NADPH oxidase. In these patients polymorphonuclear leucocytes phagocytose invading bacteria normally but are unable to kill ingested micro organism because engulfment of bacteria is not followed by activation of oxygen-dependent killing mechanism. The bacteria involved in the recurrent infections are catalase positive organisms such as staphylococci and coliforms Leucocytes from these patients fail to reduce nitroblue tetrazolium (NBT) during phagocytosis. This property has been used (NBT test) for diagnosis of CGD