CHICAGO — The combination of intestinal ultrasound and fecal calprotectin assessment at 3 months following ileocecal resection predicted patients who would experience endoscopic recurrence of Crohn’s disease at 6 months in a multi-center, prospective, observational study.

Together, these tests identified a high-risk population for endoscopic recurrence with a specificity of 94% and a positive predictive value of 81%, Maarten Pruijt, PhD candidate and researcher in the Department of Gastroenterology and Hepatology at Amsterdam UMC, Locatie VUmc, in Amsterdam, Netherlands, said at Digestive Disease Week (DDW) 2026.

“These findings support a paradigm shift toward noninvasive, risk-stratified postoperative monitoring, and may warrant incorporation into future guidelines,” Pruijt, and colleagues wrote in their abstract.

Previous Research Supports Noninvasive Risk Stratification

Patients with Crohn’s disease have a 70% endoscopic recurrence at 12 months after ileocecal resection, often without any symptoms. Current guidelines recommend ileocolonoscopy 6-12 months after surgery to assess for disease recurrence.

Previous researchers also evaluated noninvasive risk stratification in this population. In a 2025 meta-analysis, for example, fecal calprotectin was associated with 76% sensitivity and 66% specificity. Sensitivity for intestinal ultrasound was 92% and specificity was 76%. The authors of the meta-analysis stated that the combination could help reduce the need for colonoscopy monitoring. Also, establishing optimal parameters for imaging could improve its specificity and promote clinical decision-making without endoscopy.

The combination of bowel wall thickness ≥ 3 mm or and fecal calprotectin levels ≥ 50 mcg/g correctly classified 75% of patients with endoscopic recurrence, Italian researchers found in a 2023 prospective cohort study of 91 patients. The investigators concluded that the combination can be used with confidence to predict postoperative recurrence without colonoscopy.

And a smaller, retrospective study of 31 patients in 2022 compared noninvasive modalities and found intestinal ultrasound outperformed fecal calprotectin. For patients with a bowel wall thickness ≥ 3.4 mm, imaging was associated with 100% sensitivity and 87% specificity. In contrast, calprotectin was associated with an area under the curve value of 72%.

Earlier Predictions in INSIGHT

Most previous research checked for recurrence risk at 6 months or longer, sometimes even years after resection, Pruijt and his colleagues noted. They launched the reductIoN and cloSe monItorinG of postoperative recurrence by intestinal ultrasound after ileocecal resection in patienTs with CroHn’s disease (INSIGHT) study to assess the utility of earlier predictions. 

The researchers evaluated 112 patients from seven inflammatory bowel disease centers across Europe and the UK. At baseline, the median patient age was 34 years, 52% were women, and they had an 8-year median duration of Crohn’s disease. Forty-five percent had a previous ileocecal resection and 13% were current smokers. Forty percent had never taken biologic therapy.

Treating physicians were free to choose postoperative medical treatment. At 3 months, nearly half of the study participants were on medical treatment, most commonly anti-TNF agents or ustekinumab.

Researchers measured bowel wall thickness and color Doppler signal in the neo-terminal ileum. Blinded central readers interpreted endoscopy videos and intestinal ultrasound cineloops.

Endoscopic recurrence was defined as a modified Rutgeerts score ≥ i2b. At 6 months, 49 patients (44%) met this definition.

At 3 months, investigators found a median bowel wall thickness of 1.98 mm in the recurrence group vs 1.4 mm in the no recurrence group. This result also was statistically different (P = .014). On logistic regression, a bowel wall thickness ≥ 2 mm remained the only significant factor, with an odds ratio (OR) of 7.3 (P = .006).

“Based on the fecal calprotectin levels, we were able to do an analysis of endoscopic occurrence and found an area under the curve of 0.66 with an optimal cutoff of 192 mcg/g or higher, which yielded a sensitivity of 51% and a specificity of 76%,” Pruijt said.

Combining these predictors yielded an OR of 11.8, with a sensitivity of 37%, a specificity of 94%; the negative predictive value was 68%. These predictors may warrant inclusion in future guidelines, the researchers noted.

A meeting attendee asked why the sensitivity was 37%. “Ultrasound in this case is a very nice test for ruling in endoscopic recurrence. We know which patients need treatment,” Pruijt said, adding that he was unsure why sensitivity was low but said it is a common finding in endoscopic remission studies.

In practical terms, patients who meet the bowel thickness and fecal calprotectin criteria may warrant earlier treatment, he continued. Lower risk patients, in contrast, might not need an endoscopy at 6 months.

Another meeting attendee questioned if foregoing a colonoscopy at 6 months was wise. Pruijt responded that he was presenting data for 3 months and 6 months, but the study is planned for 3 years. “We can see what happens in the low-risk group in the long-term,” he said. “They may not need a colonoscopy at month 6, but maybe they need one at 12 months.”

‘Really Adds to the Literature’

“This condition is challenging, and I think the goal is really important, which is to have noninvasive monitoring of patients after surgery,” said Fernando Velayos, MD, MPH, chief of gastroenterology at San Francisco Medical Center in California.

“It is important to fine tune prediction of surgical recurrence or endoscopic recurrence,” added Velayos, who also chairs the Regional Program in Inflammatory Bowel Disease at The Permanente Group Northern California.

The study “really adds to the literature” by defining early risk predictors, he said. “Obviously, the earlier we can intervene, the better. We can change the therapies for patients at risk.”

This study was independently supported. Pruijt and Velayos had no relevant financial disclosures.

Damian McNamara is a freelance contributor to Medscape Medical News. He worked full-time for Medscape and WebMD from 2018 to 2024. Damian has a BA in chemistry and an MA in science, health, and environmental reporting/journalism.