Diagnostic Value of the Derived Neutrophil-to-Lymphocyte Ratio for Acute Appendicitis

Abstract

Purpose The diagnosis of appendicitis in children can present several challenges, leading to an increased risk of complications. Herein, we aimed to evaluate the diagnostic value of the derived neutrophil-to-lymphocyte ratio (dNLR) as a novel adjunctive diagnostic tool for appendicitis. Methods This diagnostic study included patients with appendicitis and non-surgical abdominal pain (AP), who were admitted to our hospital between 2020 and 2022. White blood cell (WBC) count, neutrophil-to-lymphocyte ratio (NLR), and dNLR were compared between the two groups of patients. Results In total, 202 patients were enrolled, including 101 with acute appendicitis (69% male, age 9.9 years) and 101 with non-surgical AP (56% male, age 9.4 years). WBC, NLR, and dNLR were significantly higher in patients in the appendicitis group than in those in the non-surgical AP group (16.47 vs. 11.18 × 103 cells/mm3, p ≤ 0.0001; 9.5 vs. 3.3 p ≤ 0.0001; and 5.2 vs. 2.3 p ≤ 0.0001, respectively). The sensitivity, specificity, positive predictive value, negative predictive value, area under the receiver operating characteristic curve, and cutoff point of dNLR for the diagnosis of acute appendicitis were 71%, 74%, 73%, 72%, 0.811, and 3.78, respectively. The positive likelihood ratios for WBC count, NLR, and dNLR were 1.95, 2.05, and 2.77, respectively. Conclusions dNLR is a novel and noninvasive biomarker with high accuracy for diagnosing appendicitis. Its inclusion as an additional diagnostic tool in clinical practice may aid in determining the need for further studies in cases with ambiguous presentations and a dNLR value ≥ 3.78.