Correlation of Computed Tomography, Pathological Findings, and Clinical Outcomes for Appendicoliths in Appendicitis.

Objectives: To correlate preoperative imaging of fecaliths with what is seen in surgical specimens.

Background: Early studies considered radiological findings of appendicoliths as a contraindication for nonoperative treatment of appendicitis. There is no standard definition for what is labeled as an appendicolith radiologically and little is known about the pathological correlates of these lesions.

Methods: A single center, retrospective study of a consecutive series of adult patients who underwent appendectomy for acute appendicitis from March 2021 to February 2022 was performed. The primary outcome was concordance between preoperative cross-sectional imaging description of appendicolith with postoperative gross pathology description. Images were retrospectively reviewed by an independent radiologist, and the presence and characteristics of appendicoliths and appendices were examined.

Results: Of 88 cases of appendicitis, 86 were diagnosed preoperatively by computed tomography (CT) imaging. Appendicoliths were seen either on CT or pathology in 45 (51%) patients. Of these 45 patients, a total of 38 (84%) were identified radiographically, and 28 (62%) were identified on pathology. Of the 38 appendicoliths diagnosed on preoperative imaging, only 21 (55%) were confirmed pathologically. Additionally, of the 28 appendicoliths observed on pathology, only 21 (75%) were identified preoperatively on imaging. There was no appendiceal obstruction in 10 of the 40 cases (25%) in which retrospective radiological review identified appendicoliths.

Conclusions: Discrepancies were observed between CT and pathology findings of appendicoliths. Not all appendicoliths seem to cause appendicitis. Because the presence of appendicolith influences the treatment decisions, there is a need to standardize their radiological diagnosis and better understand their pathophysiology.