Negative appendectomy rate in the era of computed tomography
DOI:
https://doi.org/10.18203/2349-2902.isj20261985Keywords:
Acute appendicitis, Negative appendectomy, Computed tomography, Diagnostic imagingAbstract
Background: Acute appendicitis remains a diagnostic challenge. Historically, a negative appendectomy rate (NAR) of up to 20% was considered acceptable to avoid missed diagnoses. With increasing use of computed tomography (CT), the impact of routine preoperative imaging on NAR warrants further evaluation. This study assessed the negative appendectomy rate among patients undergoing preoperative CT and evaluated its diagnostic contribution.
Methods: A retrospective study was conducted including all adult patients who underwent emergency open or laparoscopic appendectomy between January 2023 and April 2025 at King Fahad Hospital Hofuf, Kingdom of Saudi Arabia. Demographic data, preoperative CT findings, inflammatory markers, operative findings, and histopathological results were reviewed. Statistical analysis was performed using statistical package for the social sciences (SPSS) version 24.
Results: A total of 386 patients were included (62.2% male), with a mean age of 29 years. All patients underwent preoperative CT imaging. A normal appendix was identified intraoperatively in five patients (1.4%). Histopathological examination revealed catarrhal appendicitis in 66%, suppurative appendicitis in 18.7%, perforated or phlegmonous appendicitis in 13%, gangrenous appendicitis in 0.6%, and normal appendix in 1.4%. One case of appendiceal carcinoid tumor was identified. Normal leukocyte counts were present in 16.6% of patients.
Conclusions: Routine preoperative CT imaging was associated with a very low negative appendectomy rate. These findings support the role of CT in reducing unnecessary appendectomies.
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