Monitoring Inflammatory Bowel Disease in Pregnancy Using Gastrointestinal Ultrasonography

Background and Aims: Inflammatory bowel disease [IBD] affects women during their childbearing years. Gastrointestinal ultrasonography [GIUS] accurately identifies disease activity in non-pregnant patients with IBD. The utility of GIUS in pregnancy has not been established. We aimed to determine the feasibility and accuracy of GIUS in the assessment of IBD during pregnancy progression. Methods: A multicentre observational study of women with IBD undergoing GIUS during pregnancy. Clinicians assessed the adequacy of bowel views and disease activity in four colonic segments and the terminal ileum. Location[s] in which views were impeded by the uterus were documented. GIUS disease activity [bowel wall thickness >3 mm] was compared with biochemical disease activity [faecal calprotectin >100 μg/g]. Results: Ninety patients and 127 GIUS examinations were included [median gestation 19 weeks, range 4-33]. Adequate colonic views were obtained in 116/127 [91%] scans. Adequate ileal views were obtained in 62/67 [93%] scans <20 weeks and 30/51 [59%] scans at 20-26 weeks. There was a positive correlation between bowel wall thickness and calprotectin [r = 0.26, p = 0.03]. GIUS delivered a specificity of 83%, sensitivity of 74%, and negative predictive value of 90% compared with calprotectin. Conclusions: GIUS is a feasible and accurate modality for monitoring IBD in pregnancy. Adequate GIUS views of the colon and terminal ileum can be obtained in the majority of patients up to 20 weeks of gestation. Beyond 20 weeks, GIUS provides good views of the colon but the terminal ileum becomes difficult to assess.