Risk scoring systems in patients with suspected acute appendicitis scheduled to laparoscopy—a single centre retrospective analysis

Background: The ideal assessment of patients with suspected appendicitis remains a matter of debate, with no national guidelines currently available in Denmark to direct clinical care. We investigated the potential benefit of validated risk scoring systems in patients with suspected appendicitis. Methods: Patients aged 16–45 years old undergoing diagnostic laparoscopy for suspected appendicitis at a single institution from 01/01/2019 to 31/12/2019 were included. The primary endpoint was the negative appendicectomy rate (NAR). Secondary endpoints included the false negative rate (FNR) and specificity of the Appendicitis Inflammatory Response Score (AIRS) and the Adult Appendicitis Score (AAS). Results: A total of 361 patients were included, of whom 188 (52.1%) were female. Appendicectomy was performed in 287 patients (79.5%). The NAR was 6.6%. Alternative diagnoses at laparoscopy were more common in females, who were less likely to proceed to appendicectomy than males (67.6% versus 92.4%, P<0.001). Pre-operative imaging was performed in 62 patients (17.2%), most commonly with computed tomography, which had an FNR and specificity of 12.6% and 83.3%. In males, the AIRS had an FNR and specificity of 7.3% and 44.4%. In females, the AAS had an FNR and specificity of 35.7% and 66.7%. Conclusions: Stratification of patients with suspected appendicitis using clinical judgement was associated with a low NAR but high rates of unnecessary laparoscopy. Risk scoring appears unhelpful in young females, in whom routine pre-operative imaging may be considered.