Delta neutrophil index and symptomatic time are effective factors for predicting perforated appendicitis

Appendicitis is a common intra-abdominal inflammatory disease, and morbidity increases with age when perforation occurs. Because, not all patients require emergency surgery, there have been numerous studies on factors for predicting perforated appendicitis. In this study, we aimed to confirm whether the delta neutrophil index (DNI) and the time from symptom onset to surgery are effective predictors for perforated appendicitis in different age groups. This was a retrospective study conducted on 542 appendicitis patients who underwent surgery at Kangdong Sacred Heart Hospital. The simple group consisted of 431 subjects, and the perforation group consisted of 111 subjects. Multiple logistic regression analyses demonstrated that age, neutrophil percentage, DNI, C-reactive protein (CRP), and symptomatic time were significant predictors of perforation. Analysis of the receiver-operating characteristic curve showed that the DNI was the most reliable predictive value. In the analyses according to age, the perforation rate was higher in the >65-year-age group; these patients also had a higher DNI, CRP, and symptomatic time. In the DNI analysis using receiver operating characteristic (ROC) analysis, the area under the curve was higher in the >65-year-age group than in other age groups. In addition, the cutoff values have been determined and perforation occurred significantly in the group with a DNI value of 2.1 or higher and a symptomatic time of 33 hours or longer. DNI is effective in predicting perforation in patients with appendicitis compared with other inflammatory factors. Furthermore, the simultaneous measurement of symptomatic time and DNI is helpful in predicting perforation and determining whether emergency surgery is necessary.