An Appraisal of Inflammatory Markers in Distinguishing Acute Uncomplicated and Complicated Appendicitis

Abstract

Background: It remains difficult to distinguish between complicated appendicitis (CAP) and uncomplicated appendicitis (UAP). There is a paucity of studies utilizing inflammatory markers to stratify the severity of acute appendicitis. This study aimed to evaluate and demonstrate the potential clinical utility of inflammatory markers as adjuncts in distinguishing CAP and UAP. Methods: A comparative observational study was performed. Patients diagnosed with acute appendicitis were categorized as (a) complicated (necrosis, perforation, abscess) and (b) uncomplicated (inflamed, edematous). Hematological indices were combined to generate the following ratios: white cell lymphocyte ratio (WLR), white cell neutrophil ratio (WNR) and neutrophil lymphocyte ratio (NLR). Parameter accuracy was assessed using summary receiver operating characteristic (sROC) curves, classification and regression tree analysis and confusion matrix generation. Results: On sROC analysis, neutrophils (area under the curve (AUC) 0.79, p < 0.001), WLR (AUC 0.79, p < 0.001) and NLR (AUC 0.79, p < 0.001) were the most accurate parameters in distinguishing CAP and UAP. White cell count (WCC; AUC 0.76, p < 0.001) and C-reactive protein (AUC 0.75, p < 0.001) were less accurate. WCC >12.25 (sensitivity 70%, specificity 68%) and NLR >5.47 (sensitivity 78%, specificity 70%) were the most accurate in identifying CAP. Conclusion: Inflammatory marker cutoff points can be generated and utilized to differentiate between UAP and CAP. This may be useful when deciding between conservative and operative management.