Abstract: Objective To analyze the risk factors of nonoperative treatment failure in children with acute appendicitis, and to improve the understanding of the disease. Methods In this retrospective study, data of 158 patients with acute appendicitis after nonoperative treatment in our hospital from January 2013 to December 2018 were analyzed, including success group (n=110) and failure group (n=48). Clinical characteristics and laboratory findings including appendiceal imaging characteristics were compared between the two groups. Logistic regression analysis was used to determine the risk factors of failure in nonoperative treatment of acute appendicitis in children. Results There were no significant differences in age, gender, duration of abdominal pain, fever, vomiting, diarrhea, abdominal distension, metastatic right lower abdominal pain and onset season between the two groups (all P＞0.05). There were no significant differences in laboratory testing at admission including white blood cells, neutrophils, lymphocytes and C-reactive protein between the two groups (all P＞0.05). The abdominal ultrasound results showed that appendiceal fecalith (31.3% vs. 4.5%, χ2=21.555) and intraluminal appendiceal fluid (39.6% vs. 12.7%, χ2=14.587) were significantly higher in failure group than those of success group (P＜0.01). However, there were no significant differences in appendiceal maximal diameter, appendiceal wall enhancement and the proportion of abdominal enlarged lymph nodes between the two groups (P＞0.05). The multiple Logistic regression analysis showed that the appendiceal fecalith (OR=11.081, 95%CI: 3.567-34.421) and intraluminal appendiceal fluid (OR=5.196, 95%CI: 2.189-12.332) were the independent predictors of failure of nonoperative treatment in children with acute appendicitis. Conclusion Appendiceal fecalith and intraluminal appendiceal fluid are the risk factors for the value of nonoperative treatment in children with acute appendicitis. Such patients should arouse the attention and take surgical treatment as early as possible.

Key words: appendicitis, child, risk factors, nonoperative treatment, appendiceal fecalith, intraluminal appendiceal fluid