IL17A and urticaria: Concerning the urticaria activity, severe group (271.51 ± 19.76 ng/l) of CSU patients had significantly higher IL-17 levels than the moderate (255.21 ± 28.56 ng/l) and mild (248.44 ± 21.30 ng/l) groups (P = 0.028 and 0.007, respectively; Fig. 2A).