IL13 and nasal cavity polyp: Besides, in severe asthma group, compared with CRS patients without nasal polyps, those with nasal polyps had higher expression of IL-13 (P = 0.004) and IL-5 (P = 0.009) in nasal tissue but similar results in other cytokines, ILC2 cell numbers, yearly decline in pulmonary functions, and post-operative ACT scores.