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Chronic granulomatous disease is a genetic disorder responsible for a defect in the NADPH oxidase of phagocytic cells. It impairs the oxidative burst necessary to the intracellular inactivation of microorganisms and predisposes to an increased risk of infections by various microorganisms, including fungi like Aspergillus spp. and other less frequently encountered or emerging fungal species. Here we review the genetic basis, pathogenesis and clinical presentation associated with fungal infections in chronic granulomatous disease as well as the current prophylaxis and newly available therapies., (© 2012 médecine/sciences – Inserm / SRMS.)

Chronic granulomatous disease (CGD) is a rare inherited disorder in which phagocytes lack NADPH oxidase activity. Patients with CGD suffer from recurrent bacterial and fungal infections because of the absence of superoxide anions (O2- degrees ) generatingsystem. The NADPH oxidase complex is composed of a membranous cytochrome b558, cytosolic proteins p67phox, p47phox, p40phox and two small GTPases Rac2 and Rap1A. Cytochrome b558 consists of two sub-units gp91phox and p22phox. The most common form of CGD is due to mutations in CYBB gene encoding gp91phox. In some rare cases, the mutated gp91phox is normally expressed but is devoided of oxidase activity. These variants called X+ CGD, have provided interesting informations about oxidase activation mechanisms. However modelization of such variants is necessary to obtain enough biological material for studies at the molecular level. A cellular model (knock-out PLB-985 cells) has been developed for expressing recombinant mutated gp91phox for functional analysis of the oxidase complex. Recent works demonstrated that this cell line genetically deficient in gp91phox is a powerful tool for functional analysis of the NADPH oxidase complex activation.