IL1A and polyarteritis nodosa: The IL-1α alarmin was significantly higher in LB/ARAD [3.54 pg/ml (0.23–19.83 pg/ml); P = 0.033] and PAN [5.03 pg/ml (0.99–72.6 pg/ml); P = 0.0011] versus control [0.41 pg/ml (0.06–16.38 pg/ml)].