Early hematologic cellular effects of IgM-enriched intravenous immunoglobulin in pediatric sepsis: a retrospective...

Immune dysregulation plays a central role in the pathophysiology of pediatric sepsis, prompting interest in adjunctive immunomodulatory therapies. IgM-enriched intravenous immunoglobulin (IgM-IVIG) has been used in selected cases of severe pediatric sepsis; however, evidence supporting its use remains limited and inconsistent. In this retrospective propensity score-matched cohort study, we evaluated early laboratory and clinical changes associated with IgM-IVIG therapy in children admitted to a tertiary pediatric intensive care unit with sepsis or septic shock. A total of 74 patients were included, of whom 37 received IgM-IVIG. Baseline demographic characteristics and disease severity scores were similar between groups. Patients treated with IgM-IVIG required more intensive organ support and had longer pediatric intensive care unit stays, while mortality rates did not differ significantly between groups. Within the first 24 h following IgM-IVIG administration, significant reductions in leukocyte and neutrophil counts were observed, accompanied by a decrease in platelet counts and an increase in mean platelet volume. No significant changes were detected in lactate levels, vasoactive-inotropic score, or other systemic inflammatory markers.

Adjunctive IgM-enriched intravenous immunoglobulin therapy in pediatric sepsis was associated with early cellular and hematological changes suggestive of immunomodulatory activity; however, these biological effects did not translate into measurable clinical benefit. Further prospective pediatric studies are needed to better define patient subgroups that may benefit from targeted immunomodulatory interventions.

• Pediatric sepsis is associated with complex immune dysregulation and high morbidity and mortality. • Evidence supporting the clinical benefit of IgM-enriched intravenous immunoglobulin in pediatric sepsis is limited.

• IgM-enriched intravenous immunoglobulin is associated with early changes in leukocyte, neutrophil, and platelet indices in pediatric sepsis. • These early cellular effects do not appear to translate into improved clinical outcomes.