Examination of factors related to pathological severity and microperforation in patients undergoing surgery for acute appendicitis

Patients suffering from appendicitis with severe pathological findings or microperforation have a poor prognosis. Therefore, when selecting treatments, it is critical to clarify the factors related to histopathological severity and the presence of microperforation in cases diagnosed as mild appendicitis. We retrospectively collected data from 357 consecutive patients diagnosed with acute appendicitis based on symptoms such as fever, physical findings, blood tests, and imaging findings who underwent surgery at the Higashiosaka City Medical Center between January 2016 and December 2020. We investigated the predictors of pathological severity and the presence or absence of microperforations. Of the 335 patients, 252 (75%) had clinically mild appendicitis. In the multivariate analysis, diameter of the appendix ≥10.9 mm (P = .0013) and C-reactive protein ≥5.0 mg/dl (P = .0011) were related to gangrenous appendicitis, with odds ratios of 2.67 (95% confidence interval: 1.23-5.80) and 3.88 (95% confidence interval: 1.71-8.77), respectively. On the other hand, the presence of an appendicolith (P = .0083) and duration from onset to surgery ≥2 days (P = .0033) were related to microperforation, with odds ratios of 6.82 (95% confidence interval: 1.64-28.4) and 3.73 (95% confidence interval: 1.21-12.4), respectively. Patients with gangrenous appendicitis or microperforation had higher rates of postoperative complications, including more cases of Clavien-Dindo classification III and longer hospital stays (P < .05). Even in cases of clinically mild appendicitis, there is a possibility of microperforation or gangrenous appendicitis. Therefore, it is essential to carefully select the treatment in cases with more than 2 days after symptom onset, a dilated appendix, and an appendicolith.