Neutrophil alkaline phosphatase (NAP) elevated in active AOSD. 141 AOSD compared to Bcell lymphoma, SLE, aPL & controls. NAP pos. correl w/ Systemic Dz activity score (R=0.71), & 0.59 for CRP/ANC/ferritin. NAP scores higher in pre-MAS, but lower w/ MAS (w/lower WBC). NAP responds https://t.co/YbYPaJUEbz