Delta neutrophil index, CRP/albumin ratio, procalcitonin, immature granulocytes, and HALP score in acute appendicitis: Best performing biomarker?

Aim: This study investigates the diagnostic accuracy of five inflammatory biomarkers - delta neutrophil index (DNI); C-reactive protein/albumin ratio (CAR); procalcitonin (PCT); immature granulocytes count (IGc); and hemoglobin, albumin, lymphocyte, platelet score (HALPs) - in detecting acute appendicitis (AA) and identifying the most reliable marker for distinguishing complicated from non-complicated cases. Materials and methods: A prospective, cross-sectional study was conducted in a tertiary hospital emergency department, including 100 histopathologically confirmed AA patients and 100 healthy controls. Biomarker levels were analyzed using receiver operating characteristic curves. Sensitivity, specificity, and optimal cut-off values were determined via the Youden index, while logistic regression identified independent predictors of complicated appendicitis (CA). Results: DNI exhibited the highest diagnostic accuracy for AA (AUC: 0.87, 95% CI: 0.821-0.919, p < 0.001) with 92% specificity and 69% sensitivity at a cut-off of 71.88. CAR (AUC: 0.853) and PCT (AUC: 0.852) showed similar performance, whereas IGc (AUC: 0.695) and HALPs (AUC: 0.627) were less effective. DNI also outperformed the Alvarado score in predicting CA (AUC: 0.698 vs 0.626) and was an independent predictor (OR: 3.18, 95% CI: 1.40-7.24, p = 0.006). Conclusions: DNI demonstrated superior diagnostic performance for AA and was the most reliable marker for identifying CA. Its integration into clinical practice may enhance early diagnosis and reduce unnecessary surgeries, improving outcomes.