PIK3CD and congenital rubella syndrome: Lastly, to investigate whether PI3K-δ activation could identify a particular subtype of CRS having distinct clinical behavior, we subdivided the CRS patients according to the extent of p110δ expression (i.e. when there was more than 2.833-fold of p110δ expression in NP tissue compared to those of control subjects, those patients were regarded as having NP with higher p110δ expression [NP p110δhi]), and then analyzed the related immune mediators and clinical parameters of those patients.