P241 Gastrointestinal ultrasonography diagnostic performance and feasibility in IBD during pregnancy: a systematic review and narrative synthesis.

Pillet, J.(1);Perrin, J.(2);Martel, M.(3);Kherad, O.(4);Restellini, S.(5)*;

(1)La Tour Hospital, Internal Medicine, Geneva, Switzerland;(2)Centre hospitalier universitaire vaudois, Gastroenterology, Lausanne, Switzerland;(3)McGill University Health Center- McGill University, Research Institute, Montreal, Canada;(4)La Tour Hospital and University of Geneva, Internal medicine, Geneva, Switzerland;(5)la Tour Hospital and University of Geneva, IBD clinic, Geneva, Switzerland;

Background

Inflammatory bowel diseases (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC) are associated to poor maternal and foetal outcomes during pregnancy, requiring a strict monitoring of the disease activity, preferably with non-invasive modalities. We aimed to evaluate the diagnostic performance and feasibility of gastrointestinal ultrasonography (GIUS) to monitor IBD activity throughout pregnancy.

Methods

A systematic literature review has been performed identifying studies the use of ultrasound modality in pregnant IBD women from date of inception until October 2022 using MEDLINE, Cochrane library, EMBASE and ISI Web of Science databases, with keywords including 1) ultrasound/ultrasonography2) pregnancy, and 3) IBD (CD and UC). Additional relevant studies were identified from cross-referencing and hand-searches of references of the retrieved articles.  We included fully published observational studies and abstracts.

Results

Overall, five studies have been selected from 263 citations. All studies were highly heterogeneous in the definition of disease activity as reference standard, GIUS protocols, and outcomes. Two of them used a cut off value of fecal calprotectin (FCP) >100 [ug/g]. In one of them, clinical scores were used when FCP value was ≥100-249 [ug/g] and FCP ≥ 250 [ug/g] was considered as an active disease independently of clinical scores. Only one study used a single reference standard with a Harvey Bradshaw Index (HBI) >4. Across these 3 studies, results suggest a relatively good specificity (range 83%-98%) but low sensitivity (range 33%-84%) to detect disease’s activity. Only 1 study analysed GIUS performance in detecting remission with a sensitivity of 80% and a specificity of 92% compared to the reference standard. The size of the uterus limits the visualization of the terminal ileum and the sigmoid from the 2nd trimester and the 3rd trimester respectively. Evaluation of the rectum remains limited.

Conclusion

GIUS is a feasible, accessible, and accurate method to monitor disease activity in IBD pregnant women. Evidence is limited though and warrants further studies with standardized reference comparator