Comparison of Contrast-enhanced versus Non-enhanced Helical Computed Tomography in the Diagnosis of Acute Appendicitis: A Meta-analysis

The aim of this review was to compare the performance of contrast-enhanced versus non-contrast-enhanced helical computed tomography (CT) for acute appendicitis as reported. A systematic search of PubMed and Embase was conducted. The sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary receiver operating characteristic curves (AUC) were evaluated using Meta-DiSc. Quality was assessed using QUADAS 2. Eight articles with 1602 patients were included. For contrast-enhanced CT, the pooled sensitivity was 0.95 (95% CI: 0.93-0.96) with a specificity of 0.94 (95%CI: 0.93-0.96). The PLR, NLR, and DOR were 14.74 (95%CI: 9.06-23.97), 0.06 (95%CI: 0.03-0.11), and 305.31 (95%CI: 107.14-870.08), respectively. For non-contrast-enhanced CT, the pooled sensitivity was 0.85 (95% CI: 0.82-0.87) with a specificity of 0.93 (95%CI: 0.92-0.95). The PLR, NLR, and DOR were 12.22 (95% CI: 9.52-15.69), 0.15 (95%CI: 0.09-0.25), 80.98 (95%CI: 41.65-157.45), respectively. The AUC was not statistically different (Z=0.737, p=0.461). This data suggest that the contrast-enhanced CT has better diagnostic performance for acute appendicitis than non-contrast CT.