Chronic Granulomatous Disease and the Nttroblue Tetrazolium (nbt) Test

Chronic granulomatous disease (CGD) is a congenital disorder characterized by severe and recurrent infections, including pneumonia and deep tissue abscesses, leading to early death from sepsis. (Curnutte and Babior 1987). Two forms of inheritance have been noted. Most cases (80-90%) show X-linked transmission, with the remaining cases being autosomal recessive. Both forms have in common a deficiency in neutrophil and macrophage NADPH-oxidase activity. The X-linked form has a defective btype cytochrome, while autosomal recessives probably carry a defective flavoprotein which cannot reduce the cytochrome. Together these two enzymes normally constitute a plama-membrane-bound short electron-transport chain, unique to phagocytes, which transports electrons from NADPH to 09. The net r e a c t i o n i s a s f o l l o w s : l