A Real-Life Evaluation of the Best Bowel Preparation Regimen Identified in the PrepRICE Trial for Capsule Endoscopies

Abstract

Background: The optimal bowel preparation regimen for a small bowel capsule endoscopy (SBCE) remains uncertain. The PrepRICE clinical trial showed that the administration of purgatives after the capsule reached the duodenum improved the mucosal visualization and diagnostic yield. However, it was limited to patients with suspected mid-gastrointestinal bleeding who met strict inclusion criteria. This work aims to report real-life results after the implementation of the new protocol and to compare them with those of the PrepRICE trial. Methods: A prospective analysis was performed on all consecutive patients who underwent an SBCE between December of 2024 and December of 2025. The quality of the small bowel visualization (QSBV), gastric transit time (GTT), small bowel transit time (SBTT), adequate visualization rate, and complete examination rate were assessed. The QSBV was evaluated according to the Brotz quantitative scale. Results: A total of 188 patients were included (52.1% male; median age 56 years [IQR 30]). The median Brotz scale scores were 9 (IQR 1), 9 (IQR 1), 8 (IQR 2), and 8 (IQR 1) in the first, second, and third terciles and overall, respectively (compared to 9, 9, 9, 9 in PrepRICE, p < 0.001). No significant differences were found in the complete examination rate (96.8% vs. 99%, p = 0.43), adequate visualization rate (91.3% vs. 92.0%, p = 0.68), GTT and SBTT. Conclusions: The real-life results were good and similar to those of the original study, with a high rate of complete examination and adequate visualization, with slightly weaker QSBV compared to that reported in the periprocedural group in the PrepRICE study yet still superior to the preprocedural groups.

1. Introduction

A small bowel capsule endoscopy (SBCE) is a noninvasive diagnostic technique that has been widely available for over 20 years that provides an intraluminal assessment of the small bowel (SB). This tool rapidly became indispensable for the study of multiple gastrointestinal disorders, particularly obscure gastrointestinal bleeding and suspected or known Crohn’s disease (CD) [1].

Mucosal visualization in an SBCE may be compromised by the presence of debris, bubbles, bile, and enteric fluid, decreasing the small bowel visibility quality (SBVQ) and, consequently, the diagnostic yield (DY) [2]. As the clear visualization of the SB through adequate cleansing is essential to optimize the DY of SBCEs, both European (1) and American [3] endoscopy societies recommend the use of bowel purgatives before an SBCE. Yet, the optimal bowel preparation regimen for SBCEs remains uncertain.

Recently, a Portuguese multicenter randomized control trial (RCT), the PrepRICE clinical trial, compared four different laxative protocols using 1 L of polyethylene glycol (PEG) + sodium ascorbate. Two protocols involved ingestion before the procedure, and two involved ingestion after the capsule reached the duodenum: (a) 0.5 L in the morning of the procedure + 0.5 L when the SB was reached or (b) 1 L only after the SB had been reached. Patients who had the administration after the capsule reached the duodenum had an improved mucosal visualization and DY. However, this study was limited to patients with suspected mid-gastrointestinal bleeding who met strict inclusion criteria [4].

Outcomes observed in real-world settings are generally inferior to those reported in clinical trials. In this context, this work aims to report real-life results (including patients with all indications and comorbidities and using different types of bowel preparation solution) after the implementation of the new protocol in our center and to compare them with those of the PrepRICE trial.

2. Results

2.1. Patient Characteristics

Between December of 2024 and December of 2025, a total of 188 patients underwent an SBCE with the OMOM HD capsule in our center, with only two (1.1%) inpatient examinations.

Baseline patient characteristics, including comorbidities, are detailed in

Table 1. Characteristics of the patients.

Characteristics	Overall n = 188
Age, y, median (IQR)	56 (30.0)
Sex at birth—male—n (%)	98 (52.1)
Comorbidities—n (%)
Arterial hypertension	82 (43.6)
Diabetes mellitus	40 (21.3)
Chronic heart disease	32 (17.0)
Chronic kidney disease	16 (8.5)
Chronic liver disease	10 (5.3)
Chronic lung disease	23 (12.2)
Cerebrovascular disease	17 (9.0)
Bedbound—n (%)	2 (1.1)

IQR, interquartile range.

. The main indications for SBCEs were iron deficiency anemia (39.4%), clinical and/or imagiological suspicion of CD (34.0%) or an assessment of the CD severity and extent (16.5%); other indications were chronic diarrhea (6.4%), refractory celiac disease (1.6%), surveillance of polyposis syndrome (1.0%) and the clarification of imagiological findings (1.0%). Nearly all patients underwent bowel preparation with 1 L of PEG + sodium ascorbate (83.7% with Plenvu and 14.8% with Moviprep—both from Norgine, Amsterdam, The Netherlands), and only two patients (1.1%) received a sodium picosulfate + magnesium citrate-based regimen (Citrafleet, Jaba Recordati, Oeiras, Portugal).

Compared with PrepRICE, statistically significant differences were observed only for age (p < 0.001). Although there was a trend toward differences in arterial hypertension (p = 0.07) and diabetes mellitus (p = 0.09), the remaining characteristics were similar—sex (p = 0.13), chronic kidney disease (p = 0.49), chronic heart failure (p = 0.31), and chronic liver disease (p = 0.45).

2.2. SCBE Completion, TTs, and Intercurrences

The complete examination rate was 96.8%, compared to 99% in PrepRICE (p = 0.43). Six cases of incomplete examination were due to ileal stenosis in CD, and only one patient did not achieve capsule expulsion within 2 weeks. Notably, half of the patients had previously undergone patency capsule testing. In the remaining patients, a patency assessment was not performed due to suspected CD in the absence of obstructive symptoms. The cases in which the SB was only partially examined were considered for additional analysis, except for evaluations of the SBTT, SBVQ of the unreached segments and adequate visualization rate.

Regarding the TT, the capsule remained in the stomach for a median of 29 min (IQR 47.5) and in the SB for a median of 224 min (IQR 213), with no significant difference found in comparison to PrepRICE (median of 30 and 191 min, p = 0.52 and p = 0.55, respectively).

Both the complete examination rates and the transit time are summarized in

Table 2. SBCE procedural characteristics.

	Real-World Data n = 188	PrepRICE n = 96	p-Value
Exam completion rate—n (%)	182 (96.8)	95 (99.0)	0.43
GTT—median (IQR)	29 (48)	30 (42)	0.52
SBTT—median (IQR)	224 (213)	191 (161)	0.55
First tercile SBVQ—median (IQR)	9 (1)	9 (2)	<0.001
Second tercile SBVQ—median (IQR)	9 (1)	9 (1)	<0.001
Third tercile SBVQ—median (IQR)	8 (2)	9 (2)	<0.001
Global SBVQ—median (IQR)	8 (1)	9 (2)	<0.001
Adequate visualization rate—n (%)	167 (91.3)	89 (92.0)	0.68

GTT, gastric transit time; IQR, interquartile range; SB, small bowel; SBTT, small bowel transit time; and SBVQ, small bowel visualization quality.

.

No adverse events were reported in our study.

Compared to the results of the preprocedural purgatives reported in the PrepRICE trial, our results had a statistically difference in the complete examination rate (93.8%, p < 0.001) and SBTT (median of 303 min, p < 0.001).

2.3. Small Bowel Visualization Quality

The median Brotz scale scores were 9 (IQR 1), 9 (IQR 1), 8 (IQR 2), and 8 (IQR 1) in the first, second, and third tercile and overall, respectively. These results were statistically different from PrepRICE (9, 9, 9, 9, respectively, all of them with p < 0.001). Overall, the visualization rate was adequate in 91.3% of exams (vs. 92%, p = 0.68). These results are summarized in Table 2.

When compared with preprocedural purgative regimens in the PrepRICE trial, our results were statistically superior across all terciles and for the overall SBVQ (p < 0.001 in all of them) and adequate visualization rate (69.7%, p < 0.001).

2.4. Diagnostic Yield

The comparison of the DY between our center and the PrepRICE results was restricted to patients with anemia, as an SCBE in the remaining patients was performed for clinical indications different from those of the PrepRICE study.

The distribution of lesions with hemorrhagic potential across SB tertiles (DY) was similar between groups. In the first tertile, positive findings were observed in 28.4% of the real-world group and 28.1% of the PrepRICE group (p = 0.97). In the second tertile, rates were 20.3% versus 15.6%, respectively (p = 0.43), while in the third tertile they were 13.5% versus 18.8% (p = 0.36). Overall, the DY positivity was nearly identical between groups (41.9% vs. 41.7%; p = 0.98) (

Table 3. Summary of the lesions detected in the SB in patients with anemia: DY (percentage of patients with lesions classified as having high bleeding potential [P2]).

Parameters—n (%)	Real-World Data n = 74	PrepRICE n = 96	p-Value
DY first tercile	21 (28.4)	27 (28.1)	0.97
DY second tercile	15 (20.3)	15 (15.6)	0.43
DY third tercile	10 (13.5)	18 (18.8)	0.36
Global DY	31 (41.9)	40 (41.7)	0.98
Angioectasia	23 (31.1)	29 (30.2)	0.88
Ulcer	11 (14.8)	5 (5.2)	0.04
Tumor	0 (0)	3 (3.1)	0.16
Other P2 finding	8 (10.8)	9 (9.4)	0.77

DY—diagnostic yield.

).

Regarding the lesion type, angioectasia was the most frequent finding in both groups (31.1% vs. 30.2%; p = 0.88). Ulcers were significantly more common in the real-world group (14.8% vs. 5.2%; p = 0.04). No statistically significant differences were observed in tumor detection (0% vs. 3.1%; p = 0.16) or in other P2 lesions (10.8% vs. 9.4%; p = 0.77) (Table 3).

For the subgroup of patients that underwent an SBCE for the suspicion of/confirmed CD, the DY is summarized in

Table 4. Summary of lesions detected in the SB in patients with suspicion of/confirmed CD: DY (percentage of patients with inflammatory/fibrotic lesions).

Parameters—n (%)	Real-World Data n = 74
DY first tercile	12 (12.6)
DY second tercile	12 (12.6)
DY third tercile	45 (47.4)
Global DY	49 (51.6)
Ulcer	23 (31.1)
Erosion	42 (44.2)
Stenosis	5 (5.3)

DY—diagnostic yield.

.

Among patients with chronic diarrhea, the diagnostic yield (DY) was 8.3% (n = 1), 0%, and 16.7% (n = 2) in the first, second, and third terciles, respectively, resulting in an overall DY of 25% (n = 3). SBCE findings included ulcers and erosions in 16.6% (n = 2) and subepithelial lesions in 8.3% (n = 1) of patients.

In patients with refractory celiac disease, the overall DY was 66.6% (n = 2), with all positive findings occurring in the first tercile (all showed SB mucosa with villous atrophy and mucosal fissuring, compatible with the diagnosis).

Regarding patients undergoing an SBCE for the surveillance of polyposis syndromes or for the clarification of imaging findings, no inflammatory lesions, polyps, or tumors were identified (DY = 0%).

3. Discussion

The presence of residue in the SB lumen in an SBCE may impair its adequate observation. This is especially relevant in the last SB tercile, a frequent location of SB lesions, where visibility tends to decline due to the accumulation of residues [5]. Consequently, suboptimal bowel cleanliness and incomplete examinations are the main contributors to false-negative SBCE results [6], leading to the repetition of the SBCE or alternative procedures as well as increasing costs [2,7].

Currently, the European Society of Gastrointestinal Endoscopy (ESGE) recommends the ingestion of 2 L of PEG, a purgative agent, along with antifoaming agents, since this has been associated with improved SB mucosal visualization [1]. Antifoaming agents have been suggested to improve SB visualization [8,9]. In addition, split-dose regimens [10] and low-volume purgative preparations (1 L of PEG) [11,12,13] have been associated with effective SB cleansing, while offering improved tolerability, thereby potentially improving patient compliance.

Over the years, several RCTs have investigated different modalities of purgative regimens for SBCEs. Two unicentric RCTs [14,15] have demonstrated that taking the purgative after the SBCE ingestion can enhance mucosal visibility. Among the three multicentric RCTs [4,16,17,18], one did not evaluate DY, two did not show differences in the DY with different timings of bowel preparation ingestion, but PrepRICE was able to demonstrate that patients who received intraprocedure purgatives had a statistically superior SBVQ, both globally and across individual terciles, with adequate visualization rates exceeding 90%, better SBTTs, higher rates of angioectasia detection and a significantly higher DY in the second and third terciles [4]. These results are consistent with a recent systematic review and meta-analysis and a meta-review and umbrella meta-analysis that demonstrated that administering purgatives closer to the time of capsule ingestion improved the rate of adequate SB cleansing, with even higher rates observed when the purgative was administered after capsule ingestion [19,20].

In this single-center real-world cohort, SBCEs achieved a high completion rate (96.8%) and favorable SB visualization quality, with no reported adverse events, supporting the safety and technical feasibility of the procedure in routine clinical practice. Completion rates and transit times were comparable to those reported in the PrepRICE trial, suggesting that the preparation protocol used did not negatively impact capsule progression. Incomplete examinations were exclusively related to ileal stenosis in patients with CD, highlighting the importance of careful patient selection and the potential role of a patency capsule evaluation in selected cases.

Although a slight decline in visualization was observed in the distal SB, which is consistent with the previous literature, the overall adequate visualization rate remained high and comparable to that reported in PrepRICE. Importantly, when compared with preprocedural purgative regimens, our protocol demonstrated a superior SBVQ across all tertiles, as well as higher adequate visualization rates. There findings reinforce the relevance of purgative timing as a key determinant of mucosal visualization.

Furthermore, the DY of the SBCE in patients with suspected SB bleeding was nearly identical to that reported in the PrepRICE study, further supporting the reproducibility of its findings in routine clinical practice. Angioectasia remained the most frequent finding in both groups, while the higher prevalence of ulcers in the real-world cohort may reflect differences in patient characteristics or clinical exposures inherent to non-controlled settings. In patients evaluated for suspected or confirmed CD, inflammatory lesions were predominantly detected in the distal small bowel, in accordance with known disease distributions, highlighting the diagnostic value of SBCEs in this population. The overall DY in CD was similar to that reported in a recent meta-analysis [21].

Importantly, these findings were obtained in a heterogeneous real-world population, including patients with multiple comorbidities, including inpatients that were bedbound or hospitalized and with a tendency toward a higher prevalence of diabetes mellitus, which have been associated with incomplete capsule endoscopies and inadequate cleanliness [22,23]. It also included broader SBCE indications and the use of different types of bowel preparation agents, as the choice of preparation was left up to individual preference. Despite these less controlled conditions, high SB visualization rates and comparable DYs were achieved. This supports the external validity of our findings and suggests that the timing of the bowel preparation may be a more critical determinant than the specific purgative agent, as reflected by the superiority over preprocedural regimens.

Our study had some limitations. First, this was an observational, single-arm study without randomization or a contemporaneous control group, and comparisons were therefore performed with historical data from the PrepRICE trial, which limits causal inferences. Second, SBCE videos were not centrally reviewed. Although all examinations were interpreted by experienced gastroenterologists trained in the use of the Brotz scale, interobserver variability cannot be excluded. Third, this was a single-center study, which may limit the generalizability of the findings to other settings with different patient populations or endoscopy workflows. The sample size may also have been insufficient to detect small but clinically relevant differences.

4. Materials and Methods

4.1. Study Design and Patient Selection

A prospective analysis was performed on all consecutive adult patients who underwent SBCE between December of 2024 and December of 2025 at our center.

All patients older than 18 years of age undergoing SBCE were considered for inclusion in our study, including any kind of procedure indication. Exclusion criteria included pregnancy, urgent SBCE performed for overt obscure gastrointestinal (GI) bleeding, severe dysphagia, prior GI surgery, and suspected or confirmed GI stenosis or obstruction.

4.2. SBCE Procedure

Our center’s current SBCE procedure protocol, which was updated in accordance with the findings of the PrepRICE trial, is summarized in

Table 5. SBCE preparation protocol.

	Indications
7 days before SBCE	Temporary suspension of oral iron supplementation and GLP-1 receptor agonists (dulaglutide, semaglutide, and tirzepatide)
The day before SBCE	Only clear liquids Last meal at 9 pm Temporary suspension of GLP-1 receptor agonists (liraglutide)
The day of the procedure	12 h fasting Usual medications should be taken with water 2 h prior to the examination, except for diabetes-related medications Administration of 100 mg simethicone and 10 mg of domperidone 20 min before SBCE ingestion Ingestion of the capsule Real-time viewer confirmation of capsule arrival in the duodenum by a gastrointestinal nurse If the capsule had not reached the duodenum after 2 h, upper endoscopy is performed to advance the capsule into the duodenum At home: Ingestion 1 L PEG + ascorbate over 1 h After completing the cleansing preparation, the patients are allowed to drink clear liquids At lunchtime, the patients are permitted to have a light low-residue meal All patients are encouraged to maintain ambulation Return to the hospital by the end of the day

GLP-1—Glucagon-like peptide-1.

. Patients were allowed to choose the type of bowel preparation solution, and all of them used the OMOM HD capsule endoscopy system.

4.3. Data Collection and Study Outcomes

The following data were collected at baseline: age, sex at birth, comorbidities (arterial hypertension, diabetes mellitus, chronic heart disease, chronic kidney disease, chronic liver disease, chronic lung disease and cerebrovascular disease), level of independence and indication for performance of SBCE. Data regarding capsule endoscopy were collected by experienced gastroenterologists from our center, which included: the quality of small bowel visualization (QSBV), gastric transit time (GTT), small bowel transit time (SBTT), adequate visualization rate (quantitative index $\ge$ 7 points), complete examination rate and DY. QSBV was evaluated according to the Brotz quantitative scale, which ranges from 0 to 10 and comprises five parameters: percentage of mucosa visualized, presence of bubbles, bile staining, residues and overall cleanliness. This scale has been proposed as the most comprehensive method for evaluating SB cleanliness in SBCE [24].

4.4. Statistical Analysis

Continuous variables are summarized as mean and standard deviation, when normally distributed, or as median and interquartile range (IQR) when nonnormally distributed. p-values for normally distributed variables were based on the analysis of variance F test, and for nonnormally distributed variables, the Mann–Whitney U test was applied. Comparisons with the PrepRICE cohort were performed using individual-level data from the original dataset. A p-value below 0.05 was considered significant. Categorical variables were summarized as percentages and tested using a chi-square test. All statistical analyses were performed using SPSS, version 29.0 (IBM SPSS Statistics, New York, NY, USA).

5. Conclusions

Results from our study suggest that the implementation of a protocol adapted from PrepRICE maintains its effectiveness outside controlled trial settings, while preserving the DY. Future multicenter prospective studies with contemporaneous control groups and pragmatic randomized designs are needed to validate these findings under real-world conditions. Additionally, an assessment of whether improved visualization translates into meaningful clinical outcomes is also warranted.