APEX1 and Fever: As shown in Figure 2, the mean level of APE1/Ref-1 in the refractory KD group was 0.803 ± 0.111 ng/mL compared to that of 0.459 ± 0.290 ng/mL in the fever group (p = 0.011) and 0.596 ± 0.044 ng/mL in non-refractory KD (p = 0.046).