Chronic granulomatous disease (CGD) is an infrequent and inherited primary immunodeficiency with significant mortality.[1] It is caused by functional impairment of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex in neutrophilic granulocytes and monocytes.[2] CGD is characterized by recurrent and severe infections, dysregulated inflammation, and autoimmunity[2] because phagocytic cells cannot produce enough hydrogen peroxide to kill catalase-positive bacteria and fungi. Here, CAT is linked to chronic granulomatous disease.