This result was in line with the retrospective studies, which showed that vitamin D deficiency status was more prevalent in CRSwNP subjects.7, 8, 9 Meanwhile, Wang and Mostafa found the 25(OH)D3 level in CRSwNP patients was significant lower than that in CRSsNP ones.7, 29 Studies have shown that vitamin D status is associated with systemic expression of dendritic cells, activation of T-cells and basic fibroblast growth factor in patients with CRSwNP. Here, FGF2 is linked to vitamin D deficiency.