Fecal Calprotectin and Imaging Have High Accuracy in Detecting Post-Surgery Crohn’s Relapse: Meta-Analysis

The researchers reported, "The meta-analysis highlights that fecal calprotectin and imaging tools like CT/MR enterography and intestinal ultrasound can effectively detect Crohn’s disease recurrence. Fecal calprotectin showed moderate accuracy, while imaging methods offered higher sensitivity. Optimized ultrasound parameters further improved specificity, making these non-invasive tools promising alternatives to colonoscopy."

Colonoscopy is currently the gold standard for detecting postoperative CD recurrence. However, the procedure is invasive, costly, and can be burdensome for patients. In this context, the study explored whether non-invasive diagnostic methods like blood and stool markers or advanced imaging could offer a reliable substitute.

The research team reviewed studies published through January 31, 2024, focusing on the diagnostic performance of C-reactive protein (CRP), fecal calprotectin, CT/MR enterography (CTE/MRE), and intestinal ultrasound (IUS) when compared with colonoscopy findings.

The key findings were as follows:

• Analysis of 17 studies involving 1,080 patients showed that CRP had a sensitivity of 45% and specificity of 83%, indicating limited effectiveness in detecting recurrence alone.
• Fecal calprotectin (threshold 50 μg/g) showed moderate diagnostic accuracy with 76% sensitivity and 66% specificity.
• Imaging methods performed better overall, with CT and MR enterography achieving 89% sensitivity and intestinal ultrasound reaching 92%.
• Specificity for CTE/MRE and IUS was 65% and 76%, respectively.
• When optimized radiographic parameters were applied, the specificity of IUS improved to 85%, enhancing its reliability for monitoring Crohn’s disease recurrence.

“These results suggest that non-invasive tools, particularly fecal calprotectin, and cross-sectional imaging, could significantly reduce the dependence on colonoscopy for routine postoperative monitoring,” the authors noted.

The findings hold particular relevance for improving patient comfort, reducing procedural risks, and lowering healthcare costs. With IUS and calprotectin showing high sensitivity, these methods may help clinicians identify early signs of CD recurrence and make timely therapeutic decisions without immediately resorting to endoscopy.

While imaging modalities like MR enterography are more resource-intensive than biomarker testing, their non-invasive nature and diagnostic accuracy could make them suitable for routine follow-up, especially when used in combination with biomarker data.

The authors concluded, "Comprehensive analysis highlights the value of non-invasive strategies in the postoperative surveillance of Crohn’s disease. Fecal calprotectin and imaging tools, especially intestinal ultrasound with optimized parameters, appear to be effective and patient-friendly options for detecting recurrence, potentially reshaping follow-up protocols in clinical practice."

Reference:

Samnani, S., Ray, C. M., Gill, P., Stein, L., Buhler, K. A., Leong, R. W., Smith, R. L., De Cruz, P., Kaplan, G. G., Seow, C. H., Lu, C., Guizzetti, L., Hoentjen, F., Marshall, J. K., Singh, S., Panaccione, R., Novak, K. L., & Ma, C. (2025). Diagnostic Accuracy of Non-Invasive Biomarkers and Imaging for Evaluating Postoperative Recurrence in Crohn’s Disease. Clinical Gastroenterology and Hepatology. https://doi.org/10.1016/j.cgh.2025.03.030