Esophagus to Small Intestine
BMJ. 2024;384:e078581
Diagnostic accuracy of magnetically guided capsule endoscopy with a detachable string for detecting oesophagogastric varices in adults with cirrhosis: Prospective multicentre study
Objective: To evaluate the diagnostic accuracy and safety of using magnetically guided capsule endoscopy with a detachable string (ds-MCE) for detecting and grading oesophagogastric varices in adults with cirrhosis.
Design: Prospective multicentre diagnostic accuracy study.
Setting: 14 medical centres in China.
Participants: 607 adults (> 18 years) with cirrhosis recruited between January 7, 2021, and August 25, 2022. Participants underwent ds-MCE (index test), followed by oesophagogastroduodenoscopy (OGD, reference test) within 48 hours. The participants were divided into development and validation cohorts in a ratio of 2:1.
Main outcome measures: The primary outcomes were the sensitivity and specificity of ds-MCE in detecting oesophagogastric varices compared with OGD. Secondary outcomes included the sensitivity and specificity of ds-MCE for detecting high-risk oesophageal varices and the diagnostic accuracy of ds-MCE for detecting high-risk oesophagogastric varices, oesophageal varices, and gastric varices.
Results: ds-MCE and OGD examinations were completed in 582 (95.9%) of the 607 participants. Using OGD as the reference standard, ds-MCE had a sensitivity of 97.5% (95% confidence interval: 95.5–98.7%) and specificity of 97.8% (94.4–99.1%) for detecting oesophagogastric varices (both p < 0.001 compared with a pre-specified 85% threshold). When using the optimal 18% threshold for luminal circumference of the oesophagus derived from the development cohort (n = 393), the sensitivity and specificity of ds-MCE for detecting high-risk oesophageal varices in the validation cohort (n = 189) were 95.8% (89.7–98.4%) and 94.7% (88.2–97.7%), respectively. The diagnostic accuracy of ds-MCE for detecting high-risk oesophagogastric varices, oesophageal varices, and gastric varices was 96.3% (92.6–98.2%), 96.9% (95.2–98.0%), and 96.7% (95.0–97.9%), respectively. Two serious adverse events occurred with OGD but none with ds-MCE.
Conclusion: The findings of this study suggest that magnetically guided capsule endoscopy with a detachable string is a highly accurate and safe diagnostic tool for detecting and grading oesophagogastric varices and is a promising alternative to oesophagogastroduodenoscopy for screening and surveillance of oesophagogastric varices in patients with cirrhosis.