Leukoglycemic index and inflammatory markers in acute abdominal pain: Comparison of non-specific pain and acute appendicitis severity

PURPOSE: The diagnosis of acute appendicitis and the early identification of complicated disease remain challenging in emergency practice. This study aimed to evaluate the potential role of the leukoglycemic index (LGI) in distinguishing acute appendicitis from non-specific acute abdominal pain and to explore its performance in identifying complicated appendicitis, in comparison with commonly used inflammatory markers. METHODS: This retrospective study included adult patients presenting with acute abdominal pain between 2017 and 2024. Patients were categorized as controls with non-specific abdominal pain, non-complicated acute appendicitis, or complicated acute appendicitis. LGI, white blood cell count (WBC), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) were calculated at admission. Multivariable logistic regression and receiver operating characteristic (ROC) analyses were performed. RESULTS: A total of 642 patients were analyzed, including 320 with acute appendicitis and 322 controls. Among patients with appendicitis, 179 (55.9%) had non-complicated and 141 (44.1%) had complicated disease. LGI was significantly higher in patients with acute appendicitis compared with controls (p < 0.001) and was independently associated with appendicitis in the adjusted multivariable model (OR 60.0, p < 0.001), with diagnostic performance comparable to WBC (AUC 0.844 vs. 0.867). In addition, age, sex, and comorbidity status were also significantly associated with appendicitis in the adjusted analysis. In patients with complicated appendicitis, LGI, NLR, WBC, and SII were significantly elevated compared with non-complicated cases (all p < 0.001). In ROC analysis for complicated appendicitis, LGI demonstrated good discriminative ability (AUC 0.857), while WBC showed an AUC of 0.826; NLR and SII showed the highest overall performance (AUC 0.951 and 0.931, respectively). CONCLUSIONS: LGI is independently associated with acute appendicitis and demonstrates diagnostic performance broadly comparable to white blood cell count. However, it does not outperform simpler, routinely available markers, and its clinical utility remains uncertain. In addition, its potential incremental value beyond established inflammatory markers was not formally assessed and therefore cannot be inferred from the present data. LGI may be considered as a complementary parameter requiring further validation.