Assistant Professor MassGeneral Hospital for Children Boston, Massachusetts, United States
Background: Early determination of disease severity in an emergency setting is paramount for improving patient outcomes and healthcare costs. Monocyte anisocytosis, quantified as monocyte distribution width (MDW), has been shown to correspond with immune dysregulation in sepsis, severe COVID-19, and Multisystem Inflammatory Syndrome in Children. Objective: We hypothesize that MDW could broadly predict illness severity related to host-immune dysregulation in children. Design/Methods: We designed a retrospective study to analyze MDW from whole blood samples that were collected and analyzed on a UniCel DxH 900 analyzer (Beckman Coulter, Inc., Brea, CA) between 4/2020-9/2022. We analyzed samples collected from children presenting to the ED, outpatient clinics, or admitted to the hospital of either Mass General for Children or Johns Hopkins Children’s Center. We analyzed samples collected from healthy children to serve as controls. Medical information was extracted from electronic medical records. Pediatric Sequential Organ Failure Assessment (pSOFA) scores were assigned to each patient. Outcomes were analyzed by t-test, and receiver operating characteristic (ROC) curve assessed accuracy of MDW in identifying disease severity. Results: We analyzed samples from 435 children presenting with illness (mean age of 8 years, range 4 days to 18 years) and 216 healthy children (mean age of 12 years, range 1 to 18 years). MDW was significantly higher in children with illness requiring hospitalization (24.9 ± 6.7 mean and standard deviation) than in healthy controls (16 ± 1.7). Those admitted with fever showed an even greater increase in MDW (27.2 ± 6.4). Children with confirmed infection and a pediatric Sequential Organ Failure Assessment (pSOFA) score >1 (signifying signs of end-organ involvement) had MDW of 28.4 ± 6.9. A ROC curve comparing infected children with a pSOFA of 0 with a pSOFA >1 displayed an area under the curve of 73, suggesting MDW may serve as a useful tool in identifying children with severe disease.
Conclusion(s): When children present to the urgent care/emergency setting with signs of infection, MDW may serve as a useful tool to aid clinicians in identifying those are at high risk for severe illness and require closer monitoring/intervention and those who may be safely discharged home for outpatient follow up. Multi-center prospective trials are underway.
