The Use of Delta Neutrophil Index and Myeloperoxidase Index for Predicting Acute Complicated Appendicitis in Children

BACKGROUND: In children with acute appendicitis, 30% to 75% present with a complication, such as perforation, and the early diagnosis of complications is known to improve outcomes. Serum delta neutrophil index (DNI) and myeloperoxidase index (MPXI) are new inflammatory markers, and thus, in the present study, the authors evaluated the predictive values of these two markers for the presence of a complication in children with acute appendicitis. METHODS: This retrospective observational study was conducted on 105 consecutive children (<12 years old) with acute appendicitis treated over a 31-month period. DNI, MPXI, C-reactive protein (CRP), and white blood cells (WBCs) were measured in an emergency department and investigated with respect to their abilities to predict the presence of acute complicated appendicitis. RESULTS: Twenty-nine of the 105 patients (median age, 9 years) were allocated to the complicated group (27.6%) and 76 to the non-complicated group (72.4%). Median serum DNI and CRP were significantly higher in the complicated group [0% vs. 2.2%, p<0.001 and 0.65 mg/dL vs. 8.0 mg/dL, p<0.001], but median MPXI was not (p = 0.316). Area under curve (AUC) for the ability of serum DNI and CRP to predict the presence of acute complicated appendicitis were 0.738 and 0.840, respectively. Multiple logistic regression analyses showed initial CRP [odds ratio 1.301, 95% confidence interval (1.092–1.549), p = 0.003] significantly predicted the presence of a complication. The optimal cutoff for serum CRP was 4.0 mg/dL (sensitivity 69%, specificity 83%, AUC 0.840). CONCLUSIONS: Although serum DNI values were significantly higher in children with acute complicated appendicitis, no evidence was obtained to support the notion that serum DNI or serum MPXI aid the differentiation of acute complicated and non-complicated appendicitis in the ED setting.