What is the primary infection risk associated with chronic granulomatous disease?

Chronic granulomatous disease (CGD) is a genetic disorder characterized by a defect in the NADPH oxidase enzyme, which leads to the inability of phagocytes to produce reactive oxygen species. This impairment leaves patients particularly susceptible to certain types of infections. The primary risk associated with CGD involves catalase-positive organisms.

These organisms have the ability to decompose hydrogen peroxide (H2O2) into water and oxygen, negating one of the few reactive oxygen species that would typically help kill pathogens in phagocytes that are unable to produce their own. As a result, individuals with CGD are prone to infections from bacteria and fungi that produce the enzyme catalase. Common pathogens include species like Staphylococcus, Aspergillus, and Burkholderia.

While patients are at risk for infections from various pathogens (including fungi and some gram-negative bacteria), the specific and heightened risk from catalase-positive organisms is the defining feature of CGD. This risk emphasizes the underlying immunological challenge faced by these patients due to their inability to effectively eliminate these particular pathogens.