Cytokine release syndrome (CRS) and Immune effector Cell-Associated Neurotoxicity Syndrome (ICANS) after Chimeric antigen receptor (CAR) T cell treatment are common, and severe CRS (sCRS) could be life threatening. IL-6 receptor antibody and steroid are recommended for CRS, but no clear strategies exist for steroid-resistant sCRS. Thus, this study reported a case of resistance to tocilizumab and pulse therapy of methylprednisolone while suffering from grade 4 CRS and ICANS. After plasma exchange for two times and continuous renal replacement treatment combined with ruxolitinib, the patient survived with only renal injury, and achieved complete remission with negative minimal residual disease.

Background: In pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL), the IKZF1 gene deletions is an molecular marker of poor prognosis. We aimed to assess the prognostic effect of different levels of IKZF1 gene deletions in pediatric BCP-ALL. Procedure: IKZF1 Δ2-8/ALB deletions were quantified using multiplex real-time quantitative PCR (RQ-PCR) in newly diagnosed pediatric BCP-ALL patients between June 2014 and January 2018. Seventy-four patients with IKZF1 deletions of ≥ 0.01% were included. Clinical characteristics, laboratory data, and treatment outcomes were analyzed. Results: The patients were divided into two groups: IKZF1 deletions of < 1% (Group A) and of ≥ 1% (Group B). Patients in group B had a higher BCR-ABL1 positive rate than those in group A (P = 0.001). The proportions of patients who had an age at onset of ≥10 years old, and white blood cell count ≥ 50×109/L were significantly higher in group B than in group A (P < 0.05). The 3-year overall survival (OS) and 3-year event-free survival (EFS) rates in group B were 79 ± 8.8% and 62.4 ± 9.7%, respectively, which were significantly lower than the 3-year OS (97.7 ± 2.2%, P = 0.022) and 3-year EFS (83.2 ± 5.8%, P = 0.019) in group A. Multivariate analysis revealed that the level of IKZF1 deletions of ≥ 1% and CNSL were independent risk factors of EFS. Conclusions: Pediatric BCP-ALL patients with high levels of IKZF1 gene deletions have a poorer prognosis than those with low levels.