P299 Ulcerative Colitis Severity Assessment through Abdominal Ultrasonography: A Diagnostic Accuracy Meta-analysis

Abstract

Abstract Background Ulcerative colitis, a prevalent form of inflammatory bowel disease, necessitates a precise evaluation of disease severity. While effective, traditional diagnostic methods like colonoscopy are invasive and uncomfortable for patients. Abdominal ultrasonography offers a non-invasive alternative for this assessment, but its differential accuracy in evaluating disease severity in the right and left colon is not fully explored.This study aims to assess the diagnostic accuracy of abdominal ultrasonography in determining the severity of ulcerative colitis, focusing on its performance in the right and left colon. Methods A systematic review was conducted in PubMed, EMBASE, and the Cochrane Library, targeting studies up to June 2023. The selection criteria included studies that used abdominal ultrasonography for ulcerative colitis severity assessment, compared against histopathology or combined clinical, endoscopic, and radiological findings. Data analysis was performed using R software (version 4.0.3) with the mada package. This analysis focused on calculating sensitivity, specificity, diagnostic odds ratio, and positive and negative Likelihood Ratios for both the right and left colon, each with a 95% Confidence Interval. Results The search identified 5 studies with a total of 383 ulcerative colitis patients. In the right colon, the pooled sensitivity was 73.7% (95% CI, 57.6-85.2%, I2=0%), and specificity was 99.5% (95% CI, 1.6-100%, I2=0%). The diagnostic odds ratio was extremely high at 560.1 (95% CI, 0.04-6966551), with a positive Likelihood Ratio of 148.14 (95% CI, 0.01-1713586.1) and a negative Likelihood Ratio of 0.26 (95% CI, 0.15-0.45). In the left colon, sensitivity was higher at 93.7% (95% CI, 87.2-97%, I2=49.1%) with a specificity of 73.3% (95% CI, 41.8-91.3%, I2=70.9%). The diagnostic odds ratio for the left colon was 40.96 (95% CI, 8.67-193.62), with a positive Likelihood Ratio of 3.51 (95% CI, 1.31-9.42) and a negative Likelihood Ratio of 0.08 (95% CI, 0.04-0.19). Conclusion Abdominal ultrasonography shows promising results in assessing disease severity in ulcerative colitis, particularly in the left colon. The high specificity in the right colon is notable, but the wide confidence intervals suggest caution in interpretation, likely due to the small sample sizes and study variability. The left colon's more consistent and reliable performance indicates its suitability for routine clinical use in this region. This study highlights the need for further research with larger patient cohorts and standardized methodologies to solidify these findings and optimize ultrasonography’s role in ulcerative colitis management.