Effectiveness of pre-operative routine blood tests in predicting complicated acute appendicitis

BACKGROUND: Early prediction and diagnosis of perforation in acute appendicitis allow surgeons to choose the most appropriate treatment. The purpose of this study is to evaluate whether pre-operative routine laboratory examinations have a role in predicting complicated acute appendicitis. METHODS: In the study, 783 patients operated with the diagnosis of acute appendicitis between the years 2014 and 2019 were analyzed retrospectively. Among the patients with non-perforated and perforated acute appendicitis, pre-operative laboratory tests include leukocyte (WBC), neutrophil, lymphocyte, platelet (PLT), mean platelet volume (MPV), platelet distribution width (PDW), C-reactive protein (CRP), and neutrophil-to-lymphocyte rate (NLR) parameters were compared. RESULTS: Appendicitis was not detected histopathologically in 81 cases. In the study, 89.9% (n=631) of the 702 patients were non-perforated and 10.1% (n=71) were perforated acute appendicitis cases. Perforation rate was higher in elderly patients (p<0.01). It was seen that lymphocyte count was significantly lower in the perforated group, and CRP and NLR were significantly higher (p=0.048, p=0.001, p=0.028, respectively). In the diagnosis of perforated acute appendicitis, cutoff values were 44.0 mg/dL for CRP, 7.65 for NLR and 1.7/mm(3) for lymphocytes. There was no statistical difference between the groups in terms of WBC, neutrophil, PLT, MPV, and PDW values. CONCLUSION: Low lymphocyte count, high CRP, and high NLR were found to be reliable and strong predictive parameters in the diagnosis of complicated acute appendicitis.