Clinical analysis of the related factors in acute appendicitis.

BACKGROUND: In order to determine reliable clues for early diagnosis of acute appendicitis, this study was conducted to examine the related factors in patients with clinically suspected acute appendicitis. METHODS: We retrospectively analyzed 282 patients with the clinical diagnosis of acute appendicitis at China Medical College Hospital in Taiwan from January to December 2000. To study the significant related factors of acute appendicitis, the t-test, chi-square analysis, and multivariate logistic regression analysis were used. RESULTS: There were 153 males (54.3 percent) and 129 females (45.7 percent). The mean age was 30.3+/-17.4 years (range 1 to 81). The diagnostic rate of acute appendicitis was 86.2 percent. If the combination of elevated C-reactive protein, leukocytosis and elevated neutrophil ratio was used, satisfactory specificity and positive predictive value were achieved in diagnosing acute appendicitis. After controlling for the other covariates, the multivariate logistic regression analysis showed that the significant related factors of acute appendicitis were male sex (odds ratio = 3.4; 95 percent confidence interval = 1.6 to 7.3; p <0.01) and elevated neutrophil ratio (odds ratio = 4.6; 95 percent confidence interval = 2.0 to 10.6; p <0.001). CONCLUSIONS: If an elevated neutrophil ratio was observed, the probability of acute appendicitis was increased in patients with clinically suspected acute appendicitis. Thus, neutrophil ratio appears to be a good parameter for diagnosis of acute appendicitis in primary healthcare settings.