Pediatric Intensive Care Unit Mortality Among Hematopoietic Stem Cell Transplant Recipients: An Updated Systematic Review and Meta-Analysis

Children undergoing hematopoietic stem cell transplantation (HSCT) may require pediatric intensive care unit (PICU) admission; a 2008 meta-regression reported 60% mortality. We estimated contemporary PICU mortality, temporal trends, and mortality risk factors. We searched PubMed, Scopus, and Cochrane Library from 2006 to 2026 for pediatric HSCT studies reporting PICU mortality. Estimates were pooled using a random-effects model, with temporal trends assessed by meta-regression and income-setting subgroup analyses. Of 1555 records, 35 studies including 4553 PICU admissions met inclusion criteria. PICU mortality was 37.35% (95% confidence interval [CI]: 31.54-43.54; I² = 91.6%): 36.24% (95% CI: 30.30-42.63) in high-income and 41.90% (95% CI: 23.55-63.06) in upper-middle-income countries, without significant difference (p = 0.53). PICU mortality did not correlate with cohort midpoint year (p = 0.23). Invasive mechanical ventilation (odds ratio [OR] 5.02; 95% CI: 2.30-10.99), inotropic/vasopressor support (OR 5.75; 95% CI: 3.12-10.60), and continuous renal replacement therapy (OR 3.94; 95% CI: 2.63-5.92) were associated with mortality (all p < 0.001). Mechanical ventilation remained independently associated with mortality. PICU mortality among pediatric HSCT recipients is lower than the 60% reported in 2008, but remains substantial, particularly with organ support. Data from lower-income settings are scarce, representing a major evidence gap.