IL4 and peeling skin syndrome: As shown in Figure 3C, higher levels of IL-4 and IL-17 were detected in patients with IgG4-RD as compared to HC and pSS patients (82.4 ± 16.8 pg/ml versus 24.1 ± 5.6 and 89.7 ± 48.1 pg/ml for IL-4; p < 0.0001 and p = 0.02, respectively; and 120.4 ± 65.4 pg/ml versus 15.5 ± 5.5 and 80 ± 49 pg/ml for IL-17; p = 0.006 and p = 0.01, respectively).