Evaluating monocyte distribution width in pediatric emergency care

Abstract

Background: Pediatric sepsis remains a major global health challenge, complicated by age-related variability in presentation and diagnostic uncertainty. Monocyte Distribution Width (MDW), a measure of monocyte anisocytosis automatically reported with complete blood count, has shown promise as an early biomarker for sepsis in adults. However, its clinical utility in pediatric patients remains unclear. In this study, we explored the usefulness of MDW in pediatric patients presenting to the emergency department (ED). Methods: We conducted a retrospective observational study of pediatric patients (<18 years) who presented to the ED for any cause. Patients were categorized into four groups: controls (no infection), infection, sepsis, and shock. MDW values were compared across groups and stratified by age (≤6 years and > 6 years). A receiver operating characteristic (ROC) curve analysis was performed to assess MDW diagnostic performance. Results: A total of 393 patients were enrolled: 117 controls, 183 with infection, 88 with sepsis, and 5 with shock. Overall, MDW values increased with disease severity, peaking in patients with shock. However, significant overlap was observed between infection and sepsis groups, particularly in children ≤ 6 years, where MDW was elevated even in controls. In children > 6 years, MDW showed a clearer stepwise increase across disease categories. ROC analysis revealed an AUC of 0.73 for distinguishing infected from non-infected patients at a cutoff of 24. Conclusions: MDW is a readily accessible biomarker that may aid in identifying pediatric patients with infection in emergency settings.