Derived neutrophil-to-lymphocyte ratio as a predictor of negative appendectomy in acute appendicitis

Aims: This study aimed to evaluate the association between preoperative derived neutrophil-to-lymphocyte ratio (dNLR) and negative appendectomy in patients undergoing surgery for acute appendicitis. The secondary aim was to investigate the diagnostic value of preoperative dNLR by examining its differences across the histopathology-based groups. Methods: This retrospective observational study included 669 adult patients who underwent appendectomy for a preoperative diagnosis of acute appendicitis between August 2018 and December 2023 at our hospital. Based on the histopathological results, the patients were categorized into negative appendectomy and positive appendectomy (complicated and uncomplicated) groups. Preoperative complete blood count parameters, including dNLR, were compared between the groups. The diagnostic performance of dNLR was assessed using receiver operating characteristic (ROC) curve analysis.Results: The rate of negative appendectomy was 20.3%. The negative appendectomy group had a significantly lower dNLR, leukocyte count, neutrophil count, and NLR (p