Eicosanoid receptors mRNA pattern observed suggests that down-regulation of EP1 and EP3 in CRS-NP and up-regulation EP2 and EP4 in CRS and CRS-NP groups may have some role in the development of the diseases and their regulation may not be directly linked to eosinophil activation but involve post-transcriptional events mainly related to other inflammatory cell sources. This evidence concerns the gene PTGER1 and congenital rubella syndrome.