Severe Cytokine Release Syndrome After CAR T Cell Therapy in a Pediatric Patient With Relapsed ALL

Cytokine release syndrome (CRS) is a potentially life-threatening complication of chimeric antigen receptor (CAR) T cell therapy, particularly in pediatric relapsed acute lymphoblastic leukemia (ALL).

A 7-year-old boy with early bone-marrow relapse of hypodiploid ALL received anti-CD19 CAR T cells and developed severe CRS with persistent fever, hypotension, hypoxemia, encephalopathy, and multiorgan dysfunction requiring pediatric intensive care.

He received tocilizumab, high-dose dexamethasone, continuous intravenous (IV) anakinra, and emapalumab, plus advanced supportive care (mechanical ventilation, vasopressors, and continuous renal replacement therapy). Sequential, multiagent immunomodulation was associated with transient hemodynamic stabilization.

This case highlights practical bedside sequencing and escalation for refractory pediatric CRS and suggests a potential role for continuous IV anakinra and emapalumab when first-line therapy is inadequate.