Intestinal Ultrasound Is Accurate to Determine Endoscopic Response and Remission in Patients With Moderate to Severe Ulcerative Colitis: A Longitudinal Prospective Cohort Study.

BACKGROUND & AIMS: Intestinal ultrasound (IUS) is noninvasive, cost-effective, and accurate to determine disease activity in ulcerative colitis (UC). In this study, we prospectively evaluated IUS for treatment response in a longitudinal cohort by using endoscopy and histology as gold standards. METHODS: Consecutive patients with moderate to severe UC (endoscopic Mayo score [EMS] ≥2) starting tofacitinib treatment were included. Patients were evaluated at baseline and after 8 weeks of tofacitinib induction by means of clinical, biochemical, endoscopic (EMS and UC endoscopic index for severity), histologic (Robarts Histopathologic Index) and IUS assessments. Readers of IUS, endoscopy, and histology were blinded for all other outcomes. The primary outcome was difference in bowel wall thickness (BWT) for endoscopic improvement vs no endoscopic improvement. Endoscopic remission was defined as EMS = 0, improvement as EMS ≤1, and response as a decrease of EMS ≥1. RESULTS: Thirty patients were included, with 27 patients completing follow-up. BWT correlated with EMS (ρ = 0.68, P < .0001), UC endoscopic index for severity (ρ = 0.73, P < .0001) and Robarts Histopathologic Index (ρ = 0.49, P = .002) at both time points. BWT in the sigmoid was lower in patients with endoscopic remission (1.4 mm vs 4.0 mm, P = .016), endoscopic improvement (1.8 mm vs 4.5 mm, P < .0001) and decrease in BWT was more pronounced in patients with endoscopic response (-58.1% vs -13.4%, P = .018). The most accurate cutoff values for BWT were 2.8 mm (area under the curve [AUC] 0.87) for endoscopic remission, 3.9 mm (AUC 0.92) for improvement, and decrease of 32% (AUC 0.87) for response. The submucosa was the most responsive wall layer. CONCLUSION: IUS, importantly BWT as the single most important parameter, is highly accurate to detect treatment response when evaluated against endoscopic outcomes.

Assessing Disease Activity in Pediatric Crohn's Disease Using Ultrasound: The Pediatric Crohn Disease Intestinal Ultrasound Score.

OBJECTIVES: Currently, there is no consensus on how to score Crohn disease (CD) activity assessed by intestinal ultrasound (IUS) in children. This study aimed to design an easy-to-use IUS score for disease activity in pediatric CD. METHODS: Children undergoing ileo-colonoscopy for CD assessment underwent IUS the day before ileo-colonoscopy, assessed with simple endoscopic score for CD (SES-CD). IUS features were compared to the SES-CD on segmental level. Multiple regression analyses, separately for terminal ileum (TI) and colon, were done to assess predictors of disease activity and to develop a model. RESULTS: In 74 CD patients (median 15 years, 48% female), 67 TI and 364 colon segments were assessed. Based on receiver operating characteristics curves, bowel wall thickness (BWT) was categorized into low [1 point: 2-3 mm (TI) and 1.6-2 mm (colon)], medium [2 points: 3.0-3.7 mm (TI) and 2.0-2.7 mm (colon)], and high [3 points: >3.7 mm (TI) and >2.7 mm (colon)]. In TI, only BWT was retained in the model [high BWT: odds ratio (OR) 11.50, P < 0.001]. In colon, BWT (high BWT: OR 8.63, P < 0.001) and mesenteric fat (1 point: OR 3.02, P < 0.001) were independent predictors. A pediatric Crohn disease IUS score (PCD-US) cut-off of 1 resulted in a sensitivity of 82% (95% confidence interval, CI: 65%-93%) and 85% (95% CI: 80%-89%) and a cut-off of 3 in a specificity of 88% (72%-97%) and 92% (87%-96%) for TI and colon, respectively. Inter-observer agreement was moderate for TI and colon ( K : 0.42, K : 0.49, respectively). CONCLUSIONS: The PCD-US score is an easy-to-use and reliable score to detect or rule out CD activity on segmental level in children. External validation is needed before applying this score in clinical practice.

Can 2 Different Fecal Calprotectin Assays be Used Interchangeably in IBD Treatment?

BACKGROUND: Fecal calprotectin (FC) is a biomarker for inflammation in inflammatory bowel disease (IBD). Interpretation of results can be complicated because of the use of different assays to determine FC. GOALS: To assess the agreement between 2 different assays for determining FC in patients with IBD. METHODS: Samples from adults and children with IBD were tested with 2 assays: (1) EliA 2 Calprotectin and (2) EK-Cal. Samples were uniformly tested on the same day. Interassay variability was displayed in a Bland-Altman plot. The difference in categorization of the FC result (1: 0 to 250 mg/kg, 2: 250 to 500 mg/kg, 3: >500 mg/kg) was assessed with the linear weighted κ for adults and children separately. RESULTS: A total of 171 patients [mean age: 33 (range: 7 to 81); 92 (54%) female; 117 (68%) Crohn's disease; 53 (31%) ulcerative colitis] were included. Median (interquartile ranges) FC levels were 281 mg/kg (70 to 971) (EK-Cal) and 159 mg/kg (31 to 778) (EliA 2), and the mean delta FC was 89 mg/kg. In the adult population, there was substantial agreement between the 2 assays (κ: 0.72; SE: 0.06; 95% confidence interval, 0.60-0.83) and for pediatric patients, the agreement was almost perfect (κ: 0.83; SE: 0.06; 95% confidence interval: 0.70-0.95). Five of 171 patients (all aged ≥17 y and all with colonic disease) had a difference of 2 categories (1 vs. 3) between assays. Interassay variability was the highest in category 3. CONCLUSIONS: The agreement between the EliA 2 and EK-Cal assay in this cohort of IBD patients is substantial to almost perfect. Interassay variability is higher in the highest FC category.

A Healthcare Physician Can Be Trained to Perform Intestinal Ultrasound in Children With Inflammatory Bowel Disease.

OBJECTIVES: Training healthcare physicians to perform intestinal ultrasound (IUS) during outpatient visits with equal accuracy as radiologists could improve clinical management of IBD patients. We aimed to assess whether a healthcare-physician can be trained to perform IUS, with equal accuracy compared with experienced radiologists in children with iBD, and to assess inter-observer agreement. METHODS: Consecutive children, 6 to 18 years with IBD or suspicion of IBD, who underwent ileo-colonoscopy were enrolled. iUS was performed independently by a trained healthcare-physician and a radiologist in 1 visit. Training existed of an international training curriculum for IUS. Operators were blinded for each other's IUS, and for the ileocolonoscopy. Difference in accuracy of IUS by the healthcare-physician and radiologist was assessed using areas under the ROC curve (AUROC). Inter-observer variability was assessed in terminal ileum (TI), transverse colon (TC) and descending-colon (DC), for disease activity (ie, bowel wall thickness [BWT] >2 mm with hyperaemia or fat-proliferation, or BWT >3 mm). RESULTS: We included 73 patients (median age 15, interquartile range [IQR]:13-17, 37 [51%] female, 43 [58%] with Crohn disease). AUROC ranged between 0.71 and 0.81 for the healthcare-physician and between 0.67 and 0.79 for radiologist (P  > 0.05). Inter-observer agreement for disease activity per segment was moderate (K: 0.58 [SE: 0.09], 0.49 [SE: 0.12], 0.52 [SE: 0.11] respectively for TI, TC, and DC). CONCLUSIONS: A healthcare- physician can be trained to perform IUS in children with IBD with comparable diagnostic accuracy as experienced radiologists. The interobserver agreement is moderate. Our findings support the usage of IUS in clinical management of children with IBD.

The child's perception on monitoring inflammatory bowel disease activity.

To determine the perception of children with inflammatory bowel disease (IBD) regarding monitoring tests, we first compared the reported discomfort and patient perspective during gastro-intestinal (GI)-endoscopy, magnetic resonance entrography (MRE), and ultrasound (US) and, in a second comparison, patient preference on non-invasive tests (venipuncture, sampling stool and US). A cross-sectional study in children 8-18 years undergoing an US, MRE, and GI-endoscopy for diagnosis or follow-up of IBD. After each procedure, the children filled out the Discomfort during research procedures questionnaire (DISCO-RC). Items of the DISCO-RC are as follows: nervousness, annoyance, pain, fright, boredom, and tiredness. Answers range from "not" (= 0 points) to "extremely" (= 4 points) (range total score: 0-24). Differences between the procedures were assessed with Friedman test, with subsequent Wilcoxon signed-rank test. The children were also asked which non-invasive test they preferred not to undergo regularly (venipuncture, stool-sampling, or US). Answers were analyzed with χ2-test. Forty-nine patients (27 (55%) female, median age 15 (range 9-17)) were included. The children reported to be most nervous, frightened, and tired after GI-endoscopy (median: 1, 1, 2 points, respectively), equally annoyed by MRE and GI-endoscopy (median 1 point), and equally bored by MRE and US. GI-endoscopy was ranked as most discomfortable, followed by MRE and US (total DISCO-RC scores: 7 vs. 5 vs. 2, p < 0.001). Most of the children preferred not to sample stool or perform venipuncture regularly (n = 20 (41%, both) (p < 0.001)).Conclusion: Our results suggest that the children with IBD report low discomfort after US, MRE, and GI-endoscopy. US is preferred as a monitoring tool, also among non-invasive monitoring tests. GI-endoscopy was most discomfortable. What is Known: • Children with inflammatory bowel disease need to be monitored frequently for disease activity. • Adult studies - including a systematic review - on acceptability of monitoring tools among IBD patients showed mixed results. What is New: • Children in our study ranked gastro-intestinal endoscopy as most discomfortable, followed by MRE and US. • With regard to non-invasive monitoring, most children preferred not to sample stool or perform venipuncture regularly, and preferred US.

Non-radiologist-performed abdominal point-of-care ultrasonography in paediatrics - a scoping review.

BACKGROUND: Historically, US in the paediatric setting has mostly been the domain of radiologists. However, in the last decade, there has been an uptake of non-radiologist point-of-care US. OBJECTIVE: To gain an overview of abdominal non-radiologist point-of-care US in paediatrics. MATERIALS AND METHODS: We conducted a scoping review regarding the uses of abdominal non-radiologist point-of-care US, quality of examinations and training, patient perspective, financial costs and legal consequences following the use of non-radiologist point-of-care US. We conducted an advanced search of the following databases: Medline, Embase and Web of Science Conference Proceedings. We included published original research studies describing abdominal non-radiologist point-of-care US in children. We limited studies to English-language articles from Western countries. RESULTS: We found a total of 5,092 publications and selected 106 publications for inclusion: 39 studies and 51 case reports or case series on the state-of-art of abdominal non-radiologist point-of-care US, 14 on training of non-radiologists, and 1 each on possible harms following non-radiologist point-of-care US and patient satisfaction. According to included studies, non-radiologist point-of-care US is increasingly used, but no standardised training guidelines exist. We found no studies regarding the financial consequences of non-radiologist point-of-care US. CONCLUSION: This scoping review supports the further development of non-radiologist point-of-care US and underlines the need for consensus on who can do which examination after which level of training among US performers. More research is needed on training non-radiologists and on the costs-to-benefits of non-radiologist point-of-care US.

Safety of Rapid Infliximab Infusions in Children: A Systematic Review.

OBJECTIVES: The aim of the study was to assess whether the incidence of infusion reactions (IR) increases after rapid (≤1 hour) infliximab (IFX) infusions, compared with standard (2-3 hour) infusions in children. METHODS: Systematic review including studies describing the number of IR after rapid IFX infusion in children ages 0 to 18 years. RESULTS: Four records were included (3 retrospective, n = 498, 347 standard infusions, 3703 rapid infusions). Reported incidences of IR ranged from 0% to 2% of infusions in standard groups (reported 95% confidence intervals [CIs] ranged from 0% to 7%) and from 0% to 2% of infusions in rapid groups (reported 95% CIs ranged from 0% to 12%). None of the studies included reported a significant difference in incidence of IR between the 2 groups. CONCLUSIONS: There is insufficient evidence to conclude whether the rate of IR after rapid IFX increases. The consistent finding of no increase in IR in all studies and the low rate of observed IR suggests there is no significant difference in rate of IR.

Bowel ultrasound measurements in healthy children - systematic review and meta-analysis.

BACKGROUND: Ultrasound (US) is a noninvasive method of assessing the bowel that can be used to screen for bowel pathology, such as Inflammatory Bowel Disease, in children. Knowledge about US findings of the bowel in healthy children is important for interpreting US results in cases where disease is suspected. OBJECTIVE: To assess the bowel wall thickness in different bowel segments in healthy children and to assess differences in bowel wall thickness among pediatric age categories. MATERIALS AND METHODS: We conducted a systematic search in the PubMed, Embase, Cochrane, and CINAHL databases for studies describing bowel wall thickness measured by transabdominal US in healthy children. We excluded studies using contrast agent. We calculated the pooled mean and standard deviation scores and assessed differences among age categories (0-4 years, 5-9 years, 10-14 years, 15-18 years), first with analysis of variance (ANOVA) and further with subsequent Student's t-tests for independent samples, corrected for multiple testing. RESULTS: We identified 191 studies and included 7 of these studies in the systematic review. Reported bowel wall thickness values ranged from 0.8 mm to 1.9 mm in the small bowel and from 1.0 mm to 1.9 mm in the colon. The mean colonic bowel wall thickness is larger in children ages 15-19 years compared to 0-4 years (range in difference: 0.3-0.5 mm [corrected P<0.02]). CONCLUSION: The reported upper limit of bowel wall thickness in healthy children is 1.9 mm in the small bowel and the colon, and mean thickness increases slightly with age in jejunum and colon. These values can be used as guidance when screening for bowel-related pathology in children.

Premedication with intravenous steroids does not influence the incidence of infusion reactions following infliximab infusions in pediatric inflammatory bowel disease patients-a case-control study.

PURPOSE: Infusion reactions (IR) are commonly described side effects of infliximab (IFX) infusions, often leading to discontinuation of IFX. This study aimed to investigate the influence of steroid premedication (PM) on incidence of IR in pediatric inflammatory bowel disease (PIBD) patients receiving IFX. METHODS: A case-control study in two tertiary centers in Amsterdam, The Netherlands, including PIBD patients receiving IFX. PM with steroids was part of standard care in one center (PM+) but not in the other center (PM-). Acute IR were divided into mild/severe reactions and in grade 1/2/3/4 for detailed exploration. Differences between subgroups were assessed with the T or chi-square test. Multivariate logistic regression was used to assess associations between PM and IR incidence, correcting for co-medication usage. RESULTS: We included 226 patients (91 PM+, 50% male, mean age at onset of IBD 12.7 years), receiving 3433 infusions. There was no difference between the PM+ and PM- subgroups in incidence of IR (14.3% vs. 17.0% of patients, p = 0.58) and in percentage of infusions followed by IR (1.4% in both subgroups). The OR of developing IR when using PM was 1.06 (95% CI 0.49-2.27, p = 0.89), and the OR of developing a grade 3 or 4 IR when using PM was 0.90 (95% CI 0.24-3.39, p = 0.88) when correcting for co-medication usage. CONCLUSION: The incidence of IR was low, and premedication with steroids did not decrease the incidence of IR in this cohort of PIBD patients receiving IFX. Our results indicate that PM with steroids is not indicated in PIBD to prevent IR.

The current status of non-radiologist-performed abdominal ultrasonography in paediatrics - a scoping literature review protocol.

In recent years as a result of decreasing prices and the increasing availability of portable systems, ultrasonography (US), which historically has primarily been the domain of radiologists, has become more widely available to non-radiologists as well. This has increased the use of point-of-care paediatric US performed by non-radiologists. With this scoping review, focused on abdominal imaging, we aim to gain an overview of the current practices in the paediatric setting and to assess its impact in daily practice. We present the background and study design of a scoping review for non-radiologist-performed abdominal point-of-care paediatric US using a formal scoping framework. The information shall be derived from published studies. We will submit the review report to a peer-reviewed scientific journal and explore other scientific venues for presenting the work. Based on the completed review, the officers of the European Society of Paediatric Radiology will issue a position statement on non-radiologist-performed point-of-care paediatric US.

Adherence to Polyethylene Glycol Treatment in Children with Functional Constipation Is Associated with Parental Illness Perceptions, Satisfaction with Treatment, and Perceived Treatment Convenience.

OBJECTIVES: To assess treatment adherence in children with functional constipation and to evaluate the association with parental beliefs about medication, illness perceptions, treatment satisfaction, and satisfaction with information about medication. STUDY DESIGN: A cross-sectional survey was administered among parents of children with functional constipation treated with polyethylene glycol. Adherence was measured via the Medication Adherence Report Scale (MARS-5, score 5-25), with greater scores indicating better adherence (scores ≥23 were defined as adherent). Beliefs about medication, illness perceptions, satisfaction with treatment, and satisfaction with information about treatment were measured with the Beliefs about Medication Questionnaire, the Brief Illness Perception Questionnaire, the Treatment Satisfaction Questionnaire for Medication (TSQM), and the Satisfaction with Information about Medication Questionnaire. Associations between the questionnaire scores and adherence (MARS-5 score as a continuous variable) were analyzed with regression analyses. RESULTS: In total, 43 of 115 included children (37%) were adherent (MARS-5 ≥23). Spearman rank correlation test revealed a statistically significant correlation between TSQM-convenience, TSQM-satisfaction, Brief Illness Perception Questionnaire question 8 (emotions), and the MARS-5 score (rs 0.342, P = .000; rs 0.258, P = .006; rs -0.192, P = .044), which suggests that parental perceived treatment convenience, satisfaction with treatment, and illness perceptions may affect adherence in children with functional constipation. In the hierarchical multivariate regression model, 22% of the variability of the MARS-5 score could be explained by the selected predictors. The TSQM-convenience score contributed the most to the model (ß: 0.384, P = .000). CONCLUSIONS: Parents reported low adherence rates in their children with functional constipation. Treatment inconvenience, dissatisfaction with treatment, and the emotional impact of functional constipation may negatively influence treatment adherence.

Early Intestinal Ultrasound Predicts Clinical and Endoscopic Treatment Response and Demonstrates Drug-Specific Kinetics in Moderate-to-Severe Ulcerative Colitis.

BACKGROUND: Intestinal ultrasound (IUS) is an emerging modality in monitoring disease activity in ulcerative colitis (UC). Here, we aimed to identify early IUS predictors of treatment response as evaluated by endoscopy and assessed the kinetics of IUS changes. METHODS: This prospective, longitudinal study included UC patients with endoscopic disease activity (endoscopic Mayo score [EMS] ≥2) starting anti-inflammatory treatment. Clinical scores, biochemical parameters and IUS were assessed at baseline (W0), at week 2 (W2), at W6(W6), and at the time of second endoscopy (W8-W26). Per colonic segment, endoscopic remission (EMS = 0), improvement (EMS ≤1), response (decrease in EMS ≥1), and clinical remission (Lichtiger score ≤3) were assessed and correlated with common IUS parameters. Additionally, drug-specific responsiveness of bowel wall thickness (BWT) was assessed. RESULTS: A total of 51 patients were included and followed, and 33 patients underwent second endoscopy. BWT was lower from W6 onward for patients reaching endoscopic improvement (3.0 ±â€…1.2 mm vs 4.1 ±â€…1.3 mm; P = .026), remission (2.5 ±â€…1.2 mm vs 4.1 ±â€…1.1 mm; P = .002), and clinical remission (3.01 ±â€…1.34 mm vs 3.85 ±â€…1.20 mm; P = .035). Decrease in BWT was more pronounced in endoscopic responders (-40 ±â€…25% vs -4 ±â€…28%; P = .001) at W8 to W26. At W6, BWT ≤3.0 mm (odds ratio [OR], 25.13; 95% confidence interval, 2.01-3.14; P = .012) and color Doppler signal (OR, 0.35; 95% confidence interval, 0.14-0.88; P = .026) predicted endoscopic remission and improvement, respectively. Submucosal layer thickness at W6 predicted endoscopic remission (OR, 0.09; P = .018) and improvement (OR, 0.14; P = .02). Furthermore, BWT decreased significantly at W2 for infliximab and tofacitinib and at W6 for vedolizumab. CONCLUSIONS: BWT and color Doppler signal predicted endoscopic targets already after 6 weeks of treatment and response was drug specific. IUS allows close monitoring of treatment in UC and is a surrogate marker of endoscopy.

Intestinal ultrasound (IUS) is an emerging modality to monitor treatment response in ulcerative colitis. In this study, we investigated the responsiveness of IUS parameters such as bowel wall thickness (BWT) and color Doppler signal after start of treatment and evaluated these parameters early on in treatment follow-up (week 2 and W6). We found that BWT and color Doppler signal at W2 and W6 could predict endoscopic remission and improvement later on in treatment follow-up (between W8 and W26). Furthermore, we provide accurate cutoff values for BWT to predict and determine endoscopic endpoints. The timing of monitoring treatment response is drug specific, and IUS is a surrogate marker of endoscopy.

Intestinal Ultrasound to Assess Ulcerative Colitis Disease Activity in Children: External Validation and Comparison of 2 Intestinal Ultrasound Activity Indices.

BACKGROUND: There is currently no consensus on the definition of an abnormal intestinal ultrasound (IUS) for children with ulcerative colitis (UC). This cross-sectional study aimed to externally validate and compare 2 existing IUS indices in children with UC. METHODS: Children undergoing colonoscopy for UC assessment underwent IUS the day before colonoscopy, assessed with the Mayo endoscopic subscore. The UC-IUS index and the Civitelli index were compared with the Mayo endoscopic score in the ascending, transverse, and descending colon. The area under the receiver-operating characteristic curve for detecting a Mayo endoscopic score ≥2 of both scores was compared and sensitivity and specificity were calculated. RESULTS: A total of 35 UC patients were included (median age 15 years, 39% female). The area under the receiver-operating characteristic curve was higher for the UC-IUS index in the ascending colon (0.82 [95% confidence interval (CI), 0.67-0.97] vs 0.76 [95% CI, 0.59-0.93]; P = .046) and transverse colon (0.88 [95% CI, 0.76-1.00] vs 0.77 [95% CI, 0.60-0.93]; P = .01). In the descending colon, there was no difference (0.84 [95% CI, 0.70-0.99] vs 0.84 [95% CI, 0.70-0.98]). The optimal cutoff for the UC-IUS was <1 point to rule out a Mayo endoscopic score ≥2 (sensitivity: 88%, 100%, and 90% in the ascending, transverse, and descending colon, respectively) and a Mayo endoscopic score ≥2 could be detected using a cutoff of >1 (specificity: 84%, 83%, and 87%, respectively). For the Civitelli index, in our cohort, the optimal cutoff was <1 to rule out a Mayo endoscopic score ≥2 (sensitivity 75%, 65%, and 80%, respectively) and a cutoff >1 to detect a Mayo endoscopic score ≥2 (specificity 89%, 89%, and 93%, respectively). CONCLUSIONS: In this cohort, the UC-IUS index performed better than the Civitelli index. The UC-IUS index had both a high sensitivity and specificity in this cohort, when using 1 point as cutoff for a Mayo endoscopic score ≥2.

In this prospective study, we validated and compared 2 intestinal ultrasound indices to score pediatric ulcerative colitis: the UC-IUS index and the Civitelli index. In our cohort, the UC-IUS index was more accurate.

Intestinal Ultrasound in Pediatric Inflammatory Bowel Disease: Promising, but Work in Progress.

Intestinal ultrasound (IUS) is increasingly used and promulgated as a noninvasive monitoring tool for children with inflammatory bowel disease because other diagnostic modalities such as colonoscopy and magnetic resonance imaging cause significant stress in the pediatric population. The most important parameters of inflammation that can be assessed using IUS are bowel wall thickness and hyperemia of the bowel wall. Research has shown that IUS has the potential to be a valuable additional point-of-care tool to guide treatment choice and to monitor and predict treatment response, although evidence of its accuracy and value in clinical practice is still limited. This review gives an update and overview of the current evidence on the use and accuracy of IUS in children with inflammatory bowel disease.

Diagnostic Accuracy of Transabdominal Ultrasound in Detecting Intestinal Inflammation in Paediatric IBD Patients-a Systematic Review.

BACKGROUND AND AIMS: Currently used non-invasive tools for monitoring children with inflammatory bowel disease [IBD], such as faecal calprotectin, do not accurately reflect the degree of intestinal inflammation and do not provide information on disease location. Ultrasound [US] might be of added value. This systematic review aimed to assess the diagnostic test accuracy of transabdominal US in detecting intestinal inflammation in children with IBD in both diagnostic and follow-up settings. METHODS: We systematically searched PubMed, Embase [Ovid], Cochrane Library, and CINAHL [EBSCO] databases for studies assessing diagnostic accuracy of transabdominal US for detection of intestinal inflammation in patients diagnosed or suspected of IBD, aged 0-18 years, with ileo-colonoscopy and/or magnetic resonance enterography [MRE] as reference standards. Studies using US contrast were excluded. Risk of bias was assessed with QUADAS-2. RESULTS: The search yielded 276 records of which 14 were included. No meta-analysis was performed, because of heterogeneity in study design and methodological quality. Only four studies gave a clear description of their definition for an abnormal US result. The sensitivity and specificity of US ranged from 39-93% and 90-100% for diagnosing de novo IBD, and 48-93% and 83-93% for detecting active disease during follow-up, respectively. CONCLUSIONS: The diagnostic accuracy of US in detecting intestinal inflammation as seen on MRE and/or ileo-colonoscopy in paediatric IBD patients remains inconclusive, and there is currently no consensus on defining an US result as abnormal. Prospective studies with adequate sample size and methodology are needed before US can be used in the diagnostics and monitoring of paediatric IBD.