EP.FRI.241 Negative appendicectomy rate and role of biomarkers in predicting the severity of acute appendicitis

Abstract

Aim: Acute appendicitis is the most common general surgical emergency. A recent consensus study has proposed a 10% negative appendicectomy rate. We aimed to determine the negative appendicectomy rate in our centre whilst evaluating the role of biomarkers in predicting the severity of appendicitis Methods: A single-centre retrospective analysis of consecutive laparoscopic appendicectomies from 2019-2020 was performed. Patients were categorised by severity using AAST grading system. Kruskal-Wallis test was used to compare biomarkers levels (WCC, CRP, bilirubin, neutrophil: lymphocyte ratio (NLR) and platelet:lymphocyte ratio (PLR)). T-test, ROC curve and Fisher's exact test were used to differentiate between perforated and non-perforated appendicitis and negative appendicectomy rate. WCC >=11, CRP >=50, bilirubin >=21, NLR >=6.4 and PLR >=153 were the cut-off values. Negative appendicitis was defined as normal appendix at histopathological analysis. Result(s): 224 patients were included; mean age 33.7 years, 57.1% were male. 17 patients (7.6%) had negative appendicectomy. CRP, NLR, bilirubin and PLR increase with AAST score (P<0.001). WCC >=11 (p<0.001) and NLR >=6.4 (p=0.007) predicted acute appendicitis. WCC (p=0.018), CRP (p<0.001), bilirubin (p<0.001), NLR (p<0.001), PLR (p=0.002) were predictive for appendiceal perforation. Conclusion(s): 7.6% negative appendicectomy rate in our centre is below the recommended standard of 10% and lower than other centres. In our centre, raised WCC and NLR were predictive of acute appendicitis. WCC, CRP, bilirubin, NLR and PLR may be used to distinguish between perforated and non-perforated appendicitis. Our results add to the conflicting body of evidence relating to biomarkers and the severity of appendicitis.