CAT and chronic granulomatous disease: The importance of the phagocyte NADPH oxidase is underlined by chronic granulomatous disease (CGD), a severe monogenic immunodeficiency caused by loss of individual components, which presents as susceptibility to infections with catalase-positive organisms (including Staphylococcus aureus, Salmonella, and Burkholderia species) but also with autoinflammatory manifestations, characterised by sterile granulomatous inflammation (Alimchandani et al., 2013; Salvator et al., 2015; Goldblatt et al., 1999).