The diagnostic accuracy of chromoendoscopy for dysplasia in ulcerative colitis: meta-analysis of six randomized controlled trials

Aim: The diagnostic accuracy of chromoendoscopy for dysplasia in ulcerative colitis (UC) was systematically evaluated.

Method: Original studies in any language were searched from PubMed and Embase. Meta-analysis of prospective studies that compared chromoendoscopy with histological diagnosis was carried out. Sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated for each study and pooled together; summary receiver operating characteristic (ROC) and subgroup analyses were performed, while the quality of the study and heterogeneity were assessed.

Results: Six randomized controlled trials were included, which used methylene blue or indigo carmine dye spray. The meta-analysis demonstrated a pooled sensitivity of 83.3% (95% confidence interval (CI), 35.9-99.6%), specificity of 91.3% (95% CI, 43.8-100%), and DOR of 17.544 (95% CI, 1.245-247.14). Subgroup analyses revealed that both the methylene blue dye spray subgroup and the unspecified endoscopist subgroup include the same studies, and their pooled sensitivity and specificity were 0.737 and 0.917, respectively. The other subgroup, which used indigo carmine dye spray, had overall higher sensitivity (0.930) and lower specificity (0.910).

Conclusion: Chromoendoscopy has medium to high sensitivity and a high diagnostic accuracy for dysplastic lesions in UC.