CAT and chronic granulomatous disease: We demonstrated significantly enhanced activity of antioxidant enzymes such as CAT (5.99 ± 1.88 vs. 3.3 ± 1.46 nmol/H2O2/mg of protein, p < 0.0001) and SOD (1.09 ± 0.41 vs. 0.74 ± 0.26 mU/mg of protein, p < 0.05) in the sera of patients with CGD as compared to the control group.