# Retrospective analysis of 331 acute appendicitis patients: how appendicolith and CT features aid in differentiating complicated vs. uncomplicated appendicitis

## TL;DR

This study examines how appendicoliths and CT scan features help distinguish between complicated and uncomplicated acute appendicitis in 331 patients.

## Contribution

The study identifies specific CT features and appendicolith characteristics that are independently associated with complicated appendicitis.

## Key findings

- Appendicoliths are independently associated with complicated appendicitis (OR = 1.88).
- Appendiceal diameter and moderate-severe fat stranding are significant indicators of complicated appendicitis.
- Periappendiceal air on CT scans is strongly linked to complicated appendicitis in patients with appendicoliths.

## Abstract

Appendicoliths are one of the important causes of acute appendicitis. Currently, there is no consensus on the relationship between appendicoliths and complicated appendicitis, and opinions on the treatment of appendicolith-associated appendicitis vary. This study aims to determine the significance of appendicolith in acute complicated appendicitis and to assess the characteristics of appendicoliths and Computed tomography (CT) features associated with complicated appendicitis.

A retrospective analysis was conducted on patients who underwent surgical treatment for acute appendicitis at the affiliated hospital of Qingdao University from January 2016 to October 2023. Acute appendicitis was classified into two groups with and without appendicolith based on CT findings, intraoperative observations, and postoperative pathology. The clinical data of the two groups were analyzed and compared. Further subgroup analysis was performed within the appendicolith group based on pathological findings, comparing the location, size, and number of appendicoliths, as well as the length, diameter, and CT features of the appendix.

Among 331 patients with acute appendicitis, 179 had appendicolith, of which 106 were complicated appendicitis and 73 were uncomplicated appendicitis. Among 152 patients without appendicolith, 44 had complicated appendicitis and 108 had uncomplicated appendicitis. appendicoliths were independently associated with complicated appendicitis (OR = 1.88, 95% CI: 1.04–3.40, p = 0.036). In patients with appendicolith appendicitis, three factors were independently associated with complicated appendicitis: appendiceal diameter (OR = 1.20; 95% CI: 1.03–1.40), moderate-severe fat stranding (OR = 17.61; 95% CI: 3.19–97.33), and periappendiceal air (OR = 9.78; 95% CI: 1.17–81.46).

Appendiceal appendicoliths are closely related to acute complicated appendicitis. The diameter of the appendix and moderate-severe fat stranding, periappendiceal air on CT are significant indicators for identifying complicated appendicitis in acute appendicitis with appendicolith.