Current status and future perspectives of capsule endoscopy

Capsule endoscopy for small bowel bleed: Current update

Small intestine, hitherto an obscure area for endoscopists before 2000, is now easily evaluated non-invasively using capsule endoscopy and invasively by device-assisted enteroscopies. Major advances in understanding the causes and management of small bowel diseases have been in obscure gastrointestinal (GI) bleed, currently re-named as small bowel bleed, after the discovery of capsule endoscopy. The current article is a narrative review of the technology of capsule endoscopy, its advantages and limitations, future perspective and Indian studies on its utility in patients with small bowel bleed. Till date, eight large series reporting 2319 patients with obscure GI bleed (1554 overt and 765 occult) undergoing capsule endoscopy have been reported from India. Overall yield of capsule endoscopy to detect lesions in these studies varied from 43.5% to 90%. The major causes detected in various studies for small bowel bleed include vascular malformation, portal hypertensive enteropathy, ulcer, stricture, tumor, polyps, etc. Hookworm can cause both occult as well as overt small bowel bleed as shown mainly from India. Capsule endoscopy has also been quite safe in patients with small bowel bleed as despite 0.6% to 15% retention of imaging capsule in Indian studies, development of clinically evident small bowel obstruction has rarely been reported. The major limitations of capsule endoscopy include lack of maneuvrability and therapeutic capability. Research is in progress to overcome some of the limitations of the current capsule endoscopy system. It is concluded that discovery of capsule endoscopy has brought a new paradigm in GI endoscopy and explored a hitherto unexplored area of GI tract, i.e. small bowel that continued to be a black box for the endoscopists.

Cancer pharmacomicrobiomics: targeting microbiota to optimise cancer therapy outcomes

Despite the promising advances in novel cancer therapy such as immune checkpoint inhibitors (ICIs), limitations including therapeutic resistance and toxicity remain. In recent years, the relationship between gut microbiota and cancer has been extensively studied. Accumulating evidence reveals the role of microbiota in defining cancer therapeutic efficacy and toxicity. Unlike host genetics, microbiota can be easily modified via multiple strategies, including faecal microbiota transplantation (FMT), probiotics and antibiotics. Preclinical studies have identified the mechanisms on how microbes influence cancer treatment outcomes. Clinical trials have also demonstrated the potential of microbiota modulation in cancer treatments. Herein, we review the mechanistic insights of gut microbial interactions with chemotherapy and ICIs, particularly focusing on the interplay between gut bacteria and the pharmacokinetics (eg, metabolism, enzymatic degradation) or pharmacodynamics (eg, immunomodulation) of cancer treatment. The translational potential of basic findings in clinical settings is then explored, including using microbes as predictive biomarkers and microbial modulation by antibiotics, probiotics, prebiotics, dietary modulations and FMT. We further discuss the current limitations of gut microbiota modulation in patients with cancer and suggest essential directions for future study. In the era of personalised medicine, it is crucial to understand the microbiota and its interactions with cancer. Manipulating the gut microbiota to augment cancer therapeutic responses can provide new insights into cancer treatment.

New endoscopic capsule vs upper gastrointestinal endoscopy in preoperative work-up of obese candidate for bariatric surgery: Relevance of a pilot study in the COVID-19 era

Background and study aims  Obesity represents a major health concern; bariatric surgery is the most effective treatment reducing and maintaining weight loss. The role of a routine esophagogastroduodenoscopy (EGD) prior bariatric surgery is still debated. Moreover, in this scenario of COVID-19 pandemic, EGD is even more questionable due to the procedural risk of viral transmission. A new model of video-endoscopic capsule (VEC) recently has been introduced as a good alternative to the EGD. The aim of this study was to determine if this new capsule is an adequate diagnostic alternative to EGD in the work-up of patients selected for bariatric surgery, particularly in the setting of COVID-19. Patients and methods  From January to November 2020, 27 patients selected for bariatric surgery were enrolled in this pilot study to assess for noninferiority of VEC compared to EGD in detection of upper gastrointestinal disease. Results  VEC had sensitivity, specificity, and positive and negative predictive values in identification of significant lesions of 91.3 %, 83.33 %, 98.01 %, and 51.57 %, respectively, compared with EGD as the standard criterion. The accuracy was 90.51 % (95 % CI, 73.75 %-98.18 %) and the chi-square statistic is 0.1153 ( P  = 0.73). Conclusions  Our report confirms the diagnostic noninferiority of VEC in preoperative work-up of patients selected for bariatric surgery, compared to EGD. This is very important, particularly during the COVID-19 pandemic, given the high risk of contamination with EGD. Larger multicenter studies are required to confirm our preliminary results.

Application of Structural Entropy and Spatial Filling Factor in Colonoscopy Image Classification

For finding colorectal polyps the standard method relies on the techniques and devices of colonoscopy and the medical expertise of the gastroenterologist. In case of images acquired through colonoscopes the automatic segmentation of the polyps from their environment (i.e., from the bowel wall) is an essential task within computer aided diagnosis system development. As the number of the publicly available polyp images in various databases is still rather limited, it is important to develop metaheuristic methods, such as fuzzy inference methods, along with the deep learning algorithms to improve and validate detection and classification techniques. In the present manuscript firstly a fuzzy rule set is generated and validated. The former process is based on a statistical approach and makes use of histograms of the antecedents. Secondly, a method for selecting relevant antecedent variables is presented. The selection is based on the comparision of the histograms computed from the measured values for the training set. Then the inclusion of the Rényi-entropy-based structural entropy and the spatial filling factor into the set of input variables is proposed and assessed. The beneficial effect of including the mentioned structural entropy of the entropies from the hue and saturation (H and S) colour channels resulted in 65% true positive and 60% true negative rate of the classification for an advantageously selected set of antecedents when working with HSV images.

Clinical Outcomes between P1 and P0 Lesions for Obscure Gastrointestinal Bleeding with Negative Computed Tomography and Capsule Endoscopy

BACKGROUND

A simple classification for the relevance of lesions (P0, P1, and P2; no bleeding potential, less likely to bleed, and more likely to bleed, respectively) based on capsule endoscopy (CE) findings has been used. This study aimed at investigating rebleeding rates and predictive factors of P0 and P1 lesions after obtaining negative findings in both, CE and computed tomography (CT), for patients with obscure gastrointestinal bleeding (OGIB).

METHODS

Among 193 patients resulted in negative CE findings defined as P0 or P1 lesions, 84 patients with negative results on CT images were enrolled in this study. The rebleeding rates and predictive factors were assessed in the P0 and P1 groups.

RESULTS

Overall rebleeding rate in patients with negative CT and CE was 17.9%; 18.4% in the P0 group; 17.4% in the P1 group within a median follow-up duration of 18.5 months. In the P0 and P1 groups, the cumulative rebleeding rates were 9.2%, 25.4%, and 25.4%, and 6.9%, 11.8%, and 18.6% at 12, 24, and 60 months, respectively (p = 0.97). There were no independent rebleeding associated factors in the P0 group, whereas Charlson comorbidity index (CCI) (hazard ratio (HR) = 2.019, 95% confidence interval (CI): 1.158-3.519, p = 0.013), and initial low hemoglobin (Hb) level (<8 g/dL) (HR = 15.085, 95% CI: 1.182-192.514, p = 0.037) were independent predictive factors responsible for rebleeding in the P1 group.

CONCLUSIONS

Despite having negative findings on CT and CE, patients with OGIB have a significant potential rebleeding risk. Although there was no significant difference in rebleeding rates between the P0 and P1 groups on CE, the P1 group, with CCI or low initial Hb level, should be cautiously observed after the first bleeding episode.

Double-headed small-bowel capsule endoscopy: Real-world experience from a multi-centre British study

INTRODUCTION

Capsule endoscopy (CE) is well established the investigation of small-bowel (SB) pathology. We compared the use of double-headed (DH) capsules, to conventional single-headed (SH), in a real-world patient cohort in the first multicentre British study.

METHODS

Over 9 months, patients referred for routine SBCE at 4 tertiary referral centres in the UK underwent DH CE instead of conventional SH using MiroCam^Ⓡ MC2000 as per local protocols. One head (L/R) was chosen at random and reported by an expert reviewer. The DH recordings, anonymised and randomised, reported by another expert or re-read after a 4-week interval. For each CE, numbers and types of findings and overall conclusion/diagnosis were compared between SH and DH examinations.

RESULTS

211 CEs were performed. 7 failed to reach the SB; 204 analysed. Indications were: SB bleeding (n = 94); ?SB inflammation or reassessment of known inflammatory bowel disease (IBD) (n = 84); ?SB neoplasia including suspicious radiological imaging (n = 15); and, others e.g. ?celiac disease (n = 11). For SB bleeding: 27/94 (28.7%) examinations reported differences between SH and DH readings. In 17 (18.1%) the findings were clinically significant. SH CE missed angiectasias (5 pts), SB inflammation (7 pts), oesophagitis (2 pts) and SB masses (2 pts). In 1 patient, the extent of angiectasias seen was greater on the DH reading. For IBD: findings differed in 30/84 (35.7%) of CEs; 11 (13.1%) were clinically significant. In 5, signs of active inflammation were missed by the SH reading. In 6, assessment of extent/severity differed. For?SB neoplasia findings differed in 2/15 (13.3%) of examinations. Both were clinically significant. For others: 1/11 (9.1%) examinations differed; however, not deemed clinically significant. Overall, use of DH CE impacted the diagnosis in 30/204 (14.7%).

CONCLUSIONS

The use of DH CE provides more information with the potential to change clinical diagnosis and therefore management. Therefore, the routine adoption of DH CE in SB assessment should be considered.

Use of prokinetics and other quality factors in capsule endoscopy - old and new insights (Review)

Despite the extensive recent development of different techniques for endoscopic evaluation for both diagnostic and therapeutic reasons, the small bowel remains quite difficult to visualize. Capsule endoscopy and device assisted enteroscopy are presently considered the best diagnostic tools for examination of small bowel disorders, assessing diverse pathologies such as obscure gastrointestinal bleeding, iron deficiency anemia, Crohn disease, small bowel tumors and polyposis syndromes. Like any other imagistic method, it has specific indications, and contraindications, and possibly it is more important to consider limitations. In order to obtain a better result, it is necessary to respect the procedural quality indicators. Among them the use of prokinetics - diverse pharmacological substances increasing the success rate of capsule endoscopy have raised debates. Capsule endoscopy small bowel evaluation is a reliable, non-invasive and safe with many advantages and minimum risks, with a proper selection of patients, and can be used as first line investigation.

Indications for small bowel capsule endoscopy and its safety and diagnostic yield in Mexican patients. Experience at a tertiary care hospital center

INTRODUCTION

Appearing in the year 2000, capsule endoscopy revolutionized the study of the small bowel. It is the gold standard for the study of small bowel bleeding and is considered a safe procedure.

OBJECTIVE

The aim of the present study was to identify the indications for, diagnostic yield, and safety of capsule endoscopy in Mexican patients.

MATERIALS AND METHODS

A descriptive study was conducted on the first 500 small bowel capsule endoscopies performed at a tertiary care hospital center in Mexico City. Sex, age, type of video camera employed, bowel transit time, referral diagnosis, and capsule endoscopy findings and complications were registered.

RESULTS

Mean patient age was 55years (±17.63) and 57.9% of the cases were women. Complete visualization of the small bowel was achieved in 420 capsule endoscopies (84%). Mean bowel transit time was 272.25minutes (±114.86). The most common indications for the procedure were small bowel bleeding (65.2%), search for neoplasia (14.4%), and Crohn's disease (10.2%). The presence of ulcers was the most common finding in small bowel bleeding (24.8%), followed by angioectasias (18.9%). Capsule retention was the only complication and it presented in 11 patients (2.2%).

CONCLUSIONS

Capsule endoscopy is a safe and efficacious method for studying the small bowel. The results obtained in Mexican patients were similar to those described in the international literature. The present case series is the largest reported in a Mexican population.

Capsule endoscopy for small-intestinal disorders: Current status

Small-bowel capsule endoscopy (SBCE) is used widely because of its non-invasive and patient-friendly nature. SBCE can visualize entire small-intestinal mucosa and facilitate detection of small-intestinal abnormalities. In this review article, we focus on the current status of SBCE. Several platforms for SBCE are available worldwide. Third-generation SBCE (PillCam® SB3) has a high-resolution camera equipped with an adaptive frame rate system. Several software modes have been developed to reduce the reading time for capsule endoscopy and to minimize the possibility of missing lesions. The main complication of SBCE is capsule retention. Thus, the main contraindication for SBCE is known or suspected gastrointestinal obstruction unless intestinal patency is proven. Possible indications for SBCE are obscure gastrointestinal bleeding, Crohn's disease, small-intestinal polyps and tumors, and celiac disease. Colon capsule endoscopy (CCE) can observe inflamed colonic mucosa non-invasively, and allows for the continuous and non-invasive observation of the entire intestinal tract (pan-endoscopy). Recently, application of CCE as pan-enteric endoscopy for inflammatory bowel diseases (including Crohn's disease) has been reported. In the near future, reading for CE will be assisted by artificial intelligence, and reading CE videos for long periods will not be required.

The gut microbiota influences anticancer immunosurveillance and general health

Discoveries made in the past 5 years indicate that the composition of the intestinal microbiota has a major influence on the effectiveness of anticancer immunosurveillance and thereby contributes to the therapeutic activity of immune-checkpoint inhibitors that target cytotoxic T lymphocyte protein 4 (CTLA-4) or the programmed cell death protein 1 (PD-1)-programmed cell death 1 ligand 1 (PD-L1) axis, as well as the activity of immunogenic chemotherapies. Herein, we highlight some of the bacteria, such as Akkermansia muciniphila, Bacteroides fragilis, Bifidobacterium spp. and Faecalibacterium spp., that have been associated with favourable anticancer immune responses in both preclinical tumour models and patients with cancer. Importantly, these bacteria also seem to have a positive influence on general health, thus reducing the incidence of metabolic disorders and a wide range of chronic inflammatory pathologies. We surmise that a diverse and propitious microbial ecosystem favours organismal homeostasis, particularly at the level of the cancer-immune dialogue.

Evaluation of Gastric Disease with Capsule Endoscopy

The clinical indication for capsule endoscopy has expanded from small bowel evaluation to include esophagus or colon evaluation.Nevertheless, the role of capsule endoscopy in evaluation of the stomach is very limited because of the large volume and surface.However, efforts to develop an active locomotion system for capsule manipulation in detailed gastric evaluation are ongoing, becausethe technique is non-invasive, convenient, and safe, and requires no sedation. Studies have successfully reported gastric evaluation usinga magnetic-controlled capsule endoscopy system. Advances in technology suggest that capsule endoscopy will have a major role notonly in the evaluation of gastric disorders but also in the pathologic diagnosis, intervention, and treatment of any gastrointestinal tractdisorder.

Rebleeding rate and risk factors in nonsteroidal anti-inflammatory drug-induced enteropathy

OBJECTIVE

Limited evidence is available on rebleeding due to nonsteroidal anti-inflammatory drugs (NSAIDs)-induced enteropathy. Previous studies have primarily analyzed endoscopic findings. Therefore, there is a need to evaluate their clinical implications for patients. This study aimed to evaluate the rebleeding rate and its related risk factors in patients with NSAIDs-induced enteropathy.

METHODS

Of 402 patients with obscure gastrointestinal bleeding who were evaluated with capsule endoscopy, 49 were diagnosed with NSAIDs-induced enteropathy. The clinical characteristics of the patients were retrospectively analyzed. The Charlson comorbidity index was used to stratify the comorbidities. For patients who used additional drugs that influenced their tendency to bleeding, the odds ratio was calculated and used for a quantitative comparison.

RESULTS

The rebleeding rate in patients with NSAIDs-induced enteropathy was 20.4%, within a mean duration of 23.4 months. Age ≥65 years (hazard ratio [HR] 8.628, 95% confidence interval [CI] 1.152-64.625), no additional use of mucoprotective agents (HR 11.712, 95% CI 1.278-76.098) and the continuation of NSAIDs after the first bleeding episode (HR 9.861, 95% CI 1.395-98.344) were independently related to rebleeding due to NSAIDs-induced enteropathy. The underlying comorbidities, drug-related rebleeding risk scores and therapeutic use of proton pump inhibitors were not significantly different (P = 0.209, 0.212 and 0.720, respectively).

CONCLUSIONS

Approximately one-fifth of patients with NSAIDs-induced enteropathy showed rebleeding within 2 years. A careful long-term follow-up should be offered to elderly patients with NSAIDs-induced enteropathy who need continuous NSAID treatment without the additional use of mucoprotective medications.

Is there an application for wireless capsule endoscopy in horses?

This pilot study assessed wireless capsule endoscopy in horses. Image transmission was achieved with good image quality. Time to exit the stomach was variable and identified as one limitation, together with gaps in image transmission, capsule tumbling, and inability to accurately locate the capsule. Findings demonstrate usefulness and current limitations.

Quality Indicators for Small Bowel Capsule Endoscopy

Capsule endoscopy (CE) enables evaluation of the entire mucosal surface of the small bowel (SB), which is one of the most important steps for evaluating obscure gastrointestinal bleeding. Although the diagnostic yield of SB CE depends on many clinical factors, there are no reports on quality indicators. Thus, the Korean Gut Image Study Group (KGISG) publishes an article titled, “Quality Indicators for Small Bowel Capsule Endoscopy” under approval from the Korean Society of Gastrointestinal Endoscopy (KSGE). Herein, we initially identified process quality indicators, while the structural and outcome indicators are reserved until sufficient clinical data are accumulated. We believe that outcomes of SB CE can be improved by trying to meet our proposed quality indicators.

Intraepithelial lymphocytes, scores, mimickers and challenges in diagnosing gluten-sensitive enteropathy (celiac disease)

The upper digestive tract is routinely scoped for several causes of malabsorption, and the number of duodenal biopsy specimens has increased notably in the last 10 years. Gluten-sensitive enteropathy (GSE) is an autoimmune disease, which shows an increasing prevalence worldwide and requires a joint clinico-pathological approach. The classical histopathology of GSE with partial or total villous blunting is well recognized, but the classification of GSE is not straightforward. Moreover, several mimickers of GSE with intraepithelial lymphocytosis have been identified in the last 20 years, with drug interactions and medical comorbidities adding to the conundrum. In this review, we report on the normal duodenal mucosa, the clinical presentation and laboratory diagnosis of GSE, the duodenal intraepithelial lymphocytes and immunophenotype of GSE-associated lymphocytes, the GSE mimickers, the differences "across oceans" among guidelines in diagnosing GSE, and the use of a synoptic report for reporting duodenal biopsies in both children and adults in the 21st century.

Diagnostic Value of Small Bowel Capsule Endoscopy in Isolated Ileitis: A CAPENTRY Study

BACKGROUND

Capsule endoscopy (CE) has proven to be highly effective at detecting small bowel lesions, but studies regarding the diagnostic impact of CE on ileitis are rare.

AIMS

We evaluated the diagnostic value of small bowel CE for isolated ileitis observed during ileocolonoscopy.

METHODS

The CE results in 137 patients initially diagnosed with ileitis without colonic mucosal abnormalities on ileocolonoscopy at one of eight tertiary referral centers between October 2002 and June 2015 were retrospectively analyzed.

RESULTS

Among the 137 patients with isolated ileitis observed on ileocolonoscopy, 117 (85.4%) revealed positive small bowel CE findings (85.4%). The rate of positive small bowel CE findings was 92.9% in cases of ileal aphthous ulcer or erosion, and 90.9% in cases of ileal ulcer. Among 117 positive CE cases, the most common final diagnosis by CE was Crohn's disease (CD) (n = 44, 32%). No findings were identified in 20 (14.6%) of 137 cases. Ileal erosion/ulcer, rather than findings such as nodularity and erythema or elevated erythrocyte sedimentation rate (ESR) (>10 mm/h), was significant predictive factors for positive CE findings in multivariate analysis.

CONCLUSIONS

Small bowel CE showed a high diagnostic yield (85.4%) in symptomatic patients with isolated ileitis on ileocolonoscopy. Erosion or ulcer of the small bowel was a common finding on CE (66.4%), and approximately one-third of patients were diagnosed with CD. In patients with isolated ileitis on ileocolonoscopy, CE should be considered to evaluate small bowel lesions when the patient shows an elevated ESR or when the ileitis manifests as ileal ulcer or erosion rather than a nodular or erythematous lesion.