CD79A and juvenile idiopathic arthritis: Furthermore, using the cut-off values of 25.86 AU/mL for IgA, 52% (16 of 31 samples) of JIA, 33% (18/55) of CD, 53% (31/59) of CrD, 65% (13/20) of HPF, and 4% (1/29) of PFAPA sera were above the cut-off (AAE IgA+) (Figure 1(a), Table 2).