Abstract: Objective To explore the application value of modified Alvarado score and abdominal ultrasound in the diagnosis of acute appendicitis in children, so as to provide relevant reference standards for early diagnosis of acute appendicitis in children. Methods 100 children with suspected acute appendicitis who were treated in Zhenba County Hospital of TCM from May 2018 to May 2022 were selected as the research objects, and ultrasonic abdominal examination and modified Alvarado score evaluation were carried out respectively. This paper mainly evaluated the diagnostic efficacy of abdominal ultrasound and modified Alvarado score for acute appendicitis based on the surgical and pathological results, and calculated the difference between the diagnostic efficacy of combined examination and that of single examination. Results Operative pathology showed that 83 out of 100 children suspected of acute appendicitis were diagnosed as acute appendicitis and 17 as non-specific abdominal pain. The diagnostic accuracy of abdominal ultrasound was 83.00% (83/100), the sensitivity was 91.25% (73/80), and the specificity was 50.00% (10/20). The ROC curve of abdominal ultrasound diagnosis of acute appendicitis was drawn, and the AUC was 0.712 (95% CI=0.556~0.855,P=0.004). The improved Alvarado score in patients with acute appendicitis was significantly higher than that in children with nonspecific abdominal pain, with a statistically significant difference (P<0.05). The ROC curve of the improved Alvarado score for the diagnosis of acute appendicitis showed that its AUC was 0.718 (95% CI=0.581~0.855, SE=0.070, P=0.005). The diagnostic accuracy of the modified Alvarado score alone was 86.00%, sensitivity was 70.59%, specificity was 66.27%, the diagnostic accuracy of abdominal ultrasound alone was 87.00%, sensitivity was 91.25%, specificity was 50.00%, and the diagnostic accuracy of the modified Alvarado score combined with abdominal ultrasound was 96.00%, sensitivity was 93.56%, specificity was 92.16%. The differences between the three methods were statistically significant (P<0.05). The sensitivity and specificity of the combined diagnosis were significantly higher than those of the modified Alvarado score and abdominal ultrasound (P<0.05). There was no significant difference between the modified Alvarado score and abdominal ultrasound alone (P>0.05). Conclusion The improved Alvarado score is slightly better than abdominal ultrasound in the diagnosis of acute appendicitis, but the accuracy, specificity and sensitivity of the combined detection are significantly better than any single detection measure. It is suggested that the combined detection should be extended to the differential diagnosis of acute appendicitis in children.

Key words: improved alvarado score, abdominal ultrasound, acute appendicitis in children, diagnostic performance