The role of CT in decision for acute appendicitis treatment

PURPOSE: Acute appendicitis is the most common cause of acute abdomen requiring surgery. Although the standard treatment has been surgery, it has been seen in recent years that treatment is possible with antibiotics and non-operative observation. In this study, our aim is to determine whether the computed tomography (CT) findings in patients diagnosed with acute appendicitis can be used for directing treatment. METHODS: A retrospective analysis was conducted on 138 patients with acute appendicitis who underwent CT between 2015 and 2019. In this study, medical treatment group (n = 60) versus surgical treatment group (n = 78) and successful antibiotic treatment group (n = 23) versus unsuccessful antibiotic treatment group (n = 14) were compared. Appendiceal wall thickness, appendiceal diameter, the severity of mural enhancement, intra-abdominal free fluid, the severity of periappendiceal fat stranding, size of pericecal lymph node, appendicolith, adjacent organ findings, and the CT appendicitis score of groups were compared with Pearson Chi-square and Mann–Whitney U tests. Multivariable logistic regression was used to identify predictors of surgical treatment, expressed as odds ratios (ORs) with 95% CIs. Diagnostic efficacies of appendiceal diameter, the CT appendicitis score, and the developed model were quantified by receiver operating characteristic curves. RESULTS: Appendiceal diameter (P < .001), adjacent organ findings (P = 0.041), the CT appendicitis score (P < .001), the severity of periappendiceal fat stranding (P = .002), appendicolith (P = .001), and intra-abdominal free fluid (P < .001) showed statistically significant differences between the medical and surgical treatment groups. According to the logistic regression test, if the patients are with appendiceal diameter ≥13 mm (OR = 5.1, 95% CI: 1.58-16.50), appendicolith (OR = 4, 95% CI: 1.17-13.63), and intra-abdominal free fluid (OR = 3.04, 95% CI: 1.28-7.20), surgeons should prefer surgical treatment. The area under the curves for the CT appendicitis score, the appendiceal diameter, and the model were 0.742 (95% CI: 0659-0824), 0.699 (95% CI: 0.613-0.786), and 0.745 (95% CI: 0.671-0.819), respectively. As the successful and unsuccessful medical treatment groups were compared, the only significant parameter was the severity of mural enhancement (P = .005). CONCLUSION: CT findings may be helpful in patients with uncomplicated acute appendicitis whose treatment surgeons are indecisive about. We can recommend surgical treatment in cases with appendix diameter ≥13 mm, intra-abdominal free fluid, appendicolith, high CT appendicitis score, and severe mural enhancement.