Acute Appendicitis in the Presence of Normal Inflammatory Markers: A Single Centre Retrospective Cohort Analysis

Purpose: This study aims to explore the incidence of normal inflammatory markers in patients undergoing appendectomy for acute appendicitis. Materials and Methods: This study presents a single-centre retrospective cohort analysis conducted at Sheikh Khalifa Medical City in Ajman, UAE, examining patients who underwent appendectomy for acute appendicitis between January 1, 2019, and December 31, 2023. The study cohort comprised 500 patients aged 4 to 60 years. Data were systematically extracted from electronic medical records using a standardised data extraction sheet, ensuring both consistency and accuracy in the analysis. Findings: Out of 500 patients, 368 were included in the study. The majority were male (66.8%), while females comprised 33.2%. The mean age of the patients was 23.6 years, with a standard deviation of 13 years. The sensitivity, or true positive rate, for white blood cell (WBC) counts in patients with appendicitis was found to be 71.5% (95% confidence interval: 66.8%–76.1%). In comparison, the sensitivity of C-reactive protein (CRP) was 69.8% (95% CI: 65.1%–74.5%), which is consistent with findings from previous studies. The overall sensitivity for all biomarkers, combining the true positive rates of CRP and WBC, was established at 49.2% (95% CI: 44.1%–54.3%). Conversely, the false-negative rate for WBC counts in appendicitis patients was determined to be 28.5% (95% CI: 24%–33.2%), while the false-negative rate for CRP was 30.2% (95% CI: 25.4%–34.8%). Notably, a total of 7.8% (95% CI: 5.1%–10.6%) of patients with confirmed appendicitis exhibited normal (false negative) preoperative levels of both WBC and CRP. Unique Contribution to Theory, Practice and Policy: we recommend that clinicians remain cautious regarding normal inflammatory markers in patients with a high clinical suspicion of appendicitis.