Red blood cell distribution width (RDW) as a predictor of multiple organ dysfunction in pediatric critical care: a retrospective study.

backgroundRBC distribution width is a key variable in complete blood counts, associated with immature RBC release into circulation due to various processes, including systemic inflammation. RDW correlates with elevated acute inflammatory markers like ESR, CRP, and interleukin-6, and is a biomarker in conditions like kidney disease and multiple myelomas. It independently predicts disease severity in critically ill adults and is associated with morbidity, mortality and length of stay in pediatric intensive care unit, though its potential as an early biomarker for detecting pediatric patients with multiple organ dysfunction (MODS) remains unknown.

methodsThe study retrospectively reviewed PICU patients admitted to Aga Khan University Hospital from September 2018 to December 2022, excluding those admitted for less than 48 h for elective procedures, received recent RBC transfusions, or were anemic. RDW > 14.0% was considered elevated. MODS, defined as dysfunction in two or more organs, was the primary outcome. Data included demographics, PRISM III scores, laboratory values (RDW, BUN, creatinine, CRP, etc.), and clinical outcomes. Patients were stratified into three RDW groups: <13.4%, 13.4-14.3%, and > 14.4%. Analysis focused on associations between RDW levels and MODS within the first 7 days of PICU admission.

resultsThe study included 680 patients. Higher RDW was associated with younger age and higher PRISM III scores, but not with sex. RDW Group III had longer hospital stays, higher mortality, and higher incidence of MODS, but not significant. Hemoglobin and MCHC levels were lower in Group III, whereas BUN and creatinine levels showed no significant differences across groups. The OR for MODS was highest for Group II.

conclusionsThis retrospective study evaluated the prognostic value of RDW in predicting length of stay, mortality, and early identification of MODS within seven days. Among 680 pediatric patients, higher RDW levels were associated with increased mortality, longer LOS, and higher rates of sepsis and MODS, though these findings lacked statistical significance. Elevated RDW was linked to inflammation and critical illness severity but did not correlate well with pediatric severity scores or MODS trends. Future multicenter studies are recommended to explore RDW's utility in predicting early organ dysfunction and critical illness outcomes.