Patients with sCRS exhibited higher CD19/22 CAR T Cmax and AUC0–28 d values than those with grade 0–2 CRS, but these differences were not statistically significant (P = 0.229 and P = 0.102, respectively), indicating that higher levels of CAR T cells expansion in PB may be correlated with more severe CRS. Here, CD19 is linked to congenital rubella syndrome.