Colon capsule endoscopy: Advantages,limitations and expectations. Which novelties?

Since the first reports almost ten years ago, wireless capsule endoscopy has gained new f ields of application. Colon capsule endoscopy represents a new diagnostic technology for colonic exploration. Clinical trials have shown that colon capsule endoscopy is feasible, accurate and safe in patients suffering from colonic diseases and might be a valid alternative to conventional colonoscopy in selected cases such as patients refusing conventional colonoscopy or with contraindications to colonoscopy or when colonoscopy is incomplete. Despite the enthusiasm surrounding this new technique, few clinical and randomized controlled trials are to be found in the current literature, leading to heterogeneous or controversial results. Upcoming studies are needed to prove the substantial utility of colon capsule endoscopy for colon cancer screening, especially in a low prevalence of disease population, and for other indications such as inflammatory bowel disease. Possible perspectives are critically analysed and reported in this paper.     

Colon capsule endoscopy

Wireless capsule endoscopy has become the first imaging tool for small bowel examination. Recently, new capsule endoscopy applications have been developed, such as esophageal capsule endoscopy and colon capsule endoscopy. Clinical trials results have shown that colon capsule endoscopy is feasible, accurate and safe in patients suffering from colonic diseases. It could be a good alternative in patients refusing conventional colonoscopy or when it is contraindicated. Upcoming studies are needed to demonstrate its utility for colon cancer screening and other indications such us ulcerative colitis. Comparative studies including both conventional and virtual colonoscopy are also required.     

Expanding role of capsule endoscopy in inflammatory bowel disease

Capsule endoscopy has been shown to detect small bowel inflammatory changes better than any other imaging modality. Selection criteria have been optimized to increase the yield of capsule endoscopy in patients suspected to have Crohn＇s disease. Capsule endoscopy allows for earlier diagnosis of Crohn＇s disease of the small bowel and improved diagnosis of colitis in patients where it is unclear if they suffer from Crohn＇s or ulcerative colitis. A test capsule is available to assess for small bowel strictures and thus avoid capsule retention. A common language has been developed and a new scoring index will be added to capsule software. It is envisioned that the manner in which we treat Crohn＇s disease in the future will change, based on earlier diagnosis and treatment aimed at mucosal healing rather than symptom improvement.     

Role of capsule endoscopy in inflammatory bowel disease

Videocapsule endoscopy(VCE) has revolutionized our ability to visualize the small bowel mucosa. This modality is a valuable tool for the diagnosis of obscure small bowel Crohn’s disease(CD), and can also be used for monitoring of disease activity in patients with established small-bowel CD, detection of complications such as obscure bleeding and neoplasms, evaluation of response to anti-inflammatory treatment and postoperative recurrence following small bowel resection. VCE could also be an important tool in the management of patients with unclassified inflammatory bowel disease, potentially resulting in reclassification of these patients as having CD. Reports on postoperative monitoring and evaluation of patients with ileal pouch-anal anastomosis who have developed pouchitis have recenty been published. Monitoring of colonic inflammatory activity in patients with ulcerative colitis using the recently developed colonic capsule has also been reported. Capsule endoscopy is associated with an excellent safety profile. Although retention risk is increased in patients with small bowel CD, this risk can be significanty decreased by a routine utilization of a dissolvable patency capsule preceding the ingestion of the diagnostic capsule. This paper contains an overview of the current and future clinical applications of capsule endoscopy in inflammatory bowel disease.     

Ileal pouch surgery for ulcerative colitis

Ulcerative colitis （UC） is a relapsing and remitting disease characterised by chronic mucosal and submucosal inflammation of the colon and rectum. Treatment may vary depending upon the extent and severity of inflammation. Broadly speaking medical treatments aim to induce and then maintain remission. Surgery is indicated for inflammatory disease that is refractory to medical treatment or in cases of neoplastic transformation. Approximately 25% of patients with UC ultimately require colectomy. Ileal pouch-anal anastomosis （IPAA） has become the standard of care for patients with ulcerative colitis who ultimately require colectomy. This review will examine indications for IPAA, patient selection, technical aspects of surgery, management of complications and long term outcome following this procedure.     

Microscopic colitis: Is it a spectrum of inflammatory bowel disease?

Lymphocytic and collagenous colitis are forms of microscopic colitis which typically presents in elderly patients as chronic watery diarrhea. The association between microscopic colitis and inflammatory bowel disease is weak and unclear. Lymphocytic colitis progressing to ulcerative colitis has been previously reported; however there is limited data on ulcerative colitis evolving into microscopic (lymphocytic or collagenous) colitis. We report a series of six patients with documented ulcerative colitis who subsequently were diagnosed with collagenous colitis or lymphocytic colitis suggesting microscopic colitis could be a part of the spectrum of inflammatory bowel disease. The median duration of ulcerative colitis prior to being diagnosed with microscopic colitis was 15 years. We noted complete histological and/or symptomatic remission in three out of six cases while the other three patients reverted back into ulcerative colitis suggesting lymphocytic or collagenous colitis could present as a continuum of ulcerative colitis. The exact molecular mechanism of this histological transformation or the prognostic implications is still unclear. Till then it might be prudent to follow up these patients to assess for the relapse of inflammatory bowel disease as well as for dysplasia surveillance.     

Risk for colorectal cancer in ulcerative colitis： Changes, causes and management strategies

The risk of colorectal cancer for any patient with ulcerative colitis is known to be elevated, and is estimated to be 2% after 10 years, 8% after 20 years and 18% after 30 years of disease. Risk factors for cancer include extent and duration of ulcerative colitis, primary sclerosing cholangitis, a family history of sporadic colorectal cancer, severity of histologic bowel inflammation, and in some studies, young age at onset of colitis. In this review, the authors discuss recent epidemiological trends and causes for the observed changes. Population-based studies published within the past 5 years suggest that this risk has decreased over time, despite the low frequency of colectomies. The crude annual incidence rate of colorectal cancer in ulcerative colitis ranges from approximately 0.06% to 0.16% with a relative risk of 1.0-2.75. The exact mechanism for this change is unknown; it may partly be explained by the more widespread use of maintenance therapy and surveillance colonoscopy.     

New endoscopic imaging techniques in surveillance of inflammatory bowel disease

Endoscopy plays a crucial role in the management of inflammatory bowel disease(IBD). Advancesimaging techniques allow visualization of mucosal details, tissue characteristics and cellular alteration. In particular chromoendoscopy, magnification endoscopy, confocal laser endomicroscopy and endocytoscopy seem to have the possibility to radically modify the approach to surveillance and decision making. Dyebased chromoendoscopy(DBC) and magnification chromoendoscopy improve detection of dysplasia, and evaluation of inflammatory activity and extension of ulcerative colitis and are thus considered the standard of care. Dye-less chromoendoscopy could probably replace conventional DBC for surveillance. Narrow band imaging and i-scan have shown to improve activity and extent assessment in comparison to white-light endoscopy. Confocal laser endomicroscopy(CLE) can detect more dysplastic lesions in surveillance colonoscopy and predict neoplastic and inflammatory changes with high accuracy compared to histology. This technology is best used in conjunction with chromoendoscopy, narrow-band imaging, or autofluorescence because of its minute scanning area. This combination is useful for appropriate tissue classification of mucosal lesions already detected by standard or optically enhanced endoscopy. The best combination for IBD surveillance appear to be chromoendoscopy for identification of areas of suspicion, with further examination with CLE to detect intraepithelial neoplasia. However cost, availability, and experience are still an issue.     

Optimization of the treatment with immunosuppressants and biologics in inflammatory bowel disease

Many placebo controlled trials and meta-analyses evaluated the efficacy of different drugs for the treatment of inflammatory bowel disease(IBD),including immunosuppressants and biologics.Their use is indicated in moderate to severe disease in non responders to corticosteroids and in steroid-dependent patients,as induction and maintainance treatment.Infliximab,as well as cyclosporine,is considered a second line therapy in the case of severe ulcerative colitis,or non-responders to intravenous corticosteroids.An adequate dosage and duration of therapy with thiopurines should be reached before evaluating their efficacy.Methotrexate is a valid option in patients with Crohn’s disease but its use is confined to patients who are intolerant or non-responders to thiopurines.Evidence for the use of methotrexate in ulcerative colitis is insufficient.The use of thalidomide and mycophenolate mofetil is not recommended in patients with inflammatory bowel disease,these treatments could be considered in case of failure of all other therapeutic options.In patients with moderately active ulcerative colitis,refractory to thiopurines,the use of tacrolimus is considered an alternative to biologics.An increase of the dose or a decrease in the interval of administration of biologic treatment could be useful in the presence of an incomplete clinical response.In the case of primary failure of an anti-tumor necrosis factor alpha a switch to another one should be considered.Data on the efficacy of combination therapy are up to now insufficient to consider this strategy in all IBD patients.The final outcome of the treatment should be considered the clinical remission,with mucosa healing,and not the clinical response.The evaluation of serum concentration of thiopurine methyl transferase activity,thiopurine metabolites,biologic serum levels and antibiologic antibodies could be useful for the management of the treatment but it has not been routinely applied in clinical practice.The evidence of high risk development of lymphoma and cutaneous malignancies should be considered in patients treated with immunosuppressants and biologics for a long period.     

Colorectal cancer risk in Crohn＇s disease

There is recognized increased risk for colorectal cancer in patients with inflammatory bowel disease, particularly in long-standing and extensive ulcerative colitis. There also appears to be an increased rate of intestinal cancer in Crohn＇s disease, including both colon and small bowel sites. In Crohn＇s disease, evidence suggests that detection of colorectal cancer may be delayed with a worse prognosis. Some risk factors for cancer in Crohn＇s disease include the extent of inflammatory change within the colon and the presence of bypassed or excluded segments, inclu- ding rectal ＂stump＂ cancer. In addition, the risk for other types of intestinal neoplasms may be increased in Crohn＇s disease, including lymphoma and carcinoid tumors. Earlier detection of colorectal cancer based on colonoscopy screening and surveillance may be achieved but, to date, this has not translated into a positive survival benefit. Moreover, newer staining methods and evolving micro-endoscopic techniques show promise, but have not significantly altered management. Future research should focus on development of molecular or other bio-markers that might predict future dysplasia or cancer development in Crohn＇s disease.     

5-aminosalicylic acid is an attractive candidate agent for chemoprevention of colon cancer in patients with inflammatory bowel disease

Inflammatory bowel disease (IBD) is classically subdivided into ulcerative colitis (UC) and Crohn's disease (CD). Patients with IBD have increased risk for colorectal cancer. Because the pathogenesis of colorectal carcinoma has not been entirely defined yet and there is no ideal treatment for colon cancer, cancer prevention has become increasingly important in patients with IBD. The two adopted methods to prevent the development of colon cancer in clinical practice include the prophylactic colectomy and colonoscopic surveillance. But patients and physicians seldom accept colectomy as a routine preventive method and most patients do not undergo appropriate colonoscopic surveillance. Chemoprevention refers to the use of natural or synthetic chemical agents to reverse, suppress, or to delay the process of carcinogenesis. Chemoprevention is a particularly useful method in the management of patients at high risk for the development of specific cancers based on inborn genetic susceptibility, the presence of cancer-associated disease, or other known risk factors. Prevention of colorectal cancer by administration of chemopreventive agents is one of the most promising options for IBD patients who are at increased risks of the disease. The chemopreventive efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) against intestinal tumors has been well established. But with reports that NSAIDs aggravated the symptoms of colitis, their sustained use for the purpose of cancer Chemoprevention has been relatively contraindicated in IBD patients. Another hopeful candidate Chemoprevention drug for IBD patients is 5-aminosalicylic acid (5-ASA), which is well tolerated by most patients and has limited systemic adverse effects, and no gastrointestinal toxicity. 5-ASA lacks the well-known side effects of longterm NSAIDs use. Retrospective correlative studies have suggested that the long-term use of 5-ASA in IBD patients may significantly reduce the risk of development of colorectal cancer. According to the literature, this agent might well satisfy clinical expectations with respect to a safe and effective chemopreventive agent.     

Endoscopy in inflammatory bowel disease when and why

Endoscopy plays an important role in the diagnosis and management of inflammatory bowel disease(IBD).It is useful to exclude other aetiologies,differentiate between ulcerative colitis(UC) and Crohn’s disease(CD),and define the extent and activity of inflammation.Ileocolonoscopy is used for monitoring of the disease,which in turn helps to optimize the management.It plays a key role in the surveillance of UC for dysplasia or neoplasia and assessment of post operative CD.Capsule endoscopy and double balloon enteroscopy are increasingly used in patients with CD.Therapeutic applications relate to stricture dilatation and dysplasia resection.The endoscopist’s role is vital in the overall management of IBD.     

Capsule endoscopy in celiac disease

Video capsule endoscopy is an attractive and patient- friendly tool that provides high quality images of the small bowel. Obscure gastrointestinal bleeding is the primary and most evaluated indication to capsule endoscopy; however, indications are expanding and a small number of preliminary reports have been presented concerning the role of video capsule endoscopy in the diagnosis of celiac disease. The purpose of this review is to update the current knowledge and to hypothesize on future perspectives of the use of video capsule endoscopy in patients with celiac disease.     

Capsule endoscopy in pediatrics: A 10-years journey

Video capsule endoscopy(CE) for evaluation the esophagus(ECE), small bowel(SBCE) and the colon(CCE) is particularly useful in pediatrics, because this imaging modality does not require ionizing radiation, deep sedation or general anesthesia. The risk of capsule retention appears to be dependent on indication rather than age and parallels the adult experience by indication, making SBCE a relatively safe procedure with a significant diagnostic yield. The newest indication, assessment of mucosal change, greatly enhances and expands its potential benefit. The diagnostic role of CE extends beyond the SB. The use of ECE also may enhance our knowledge of esophageal disease and assist patient care. Colon CCE is a novel minimally invasive and painless endoscopic technique allowing exploration of the colon without need for sedation, rectal intubation and gas insufflation. The limited data on ECE and CCE in pediatrics does not yet allow the same conclusions regarding efficacy; however, both appear to provide safe methods to assess and monitor mucosal change in their respective areas with little discomfort. Moreover, although experience has been limited, the patency capsule may help lessen the potential of capsule retention; and newly researched protocols for bowel cleaning may further enhance CE’s diagnostic yield. However, further research is needed to optimize the use of the various CE procedures in pediatric populations.     

A guide to diagnosis of iron deficiency and iron deficiency anemia in digestive diseases

Iron deficiency （ID）, with or without anemia, is often caused by digestive diseases and should always be investigated, except in very specific situations, as its causes could be serious diseases, such as cancer. Diagnosis of ID is not always easy. Low serum levels of ferritin or transferrin saturation, imply a situation of absolute or functional ID. It is sometimes difficult to differentiate ID anemia from anemia of chronic diseases, which can coexist. In this case, other parameters, such as soluble transferrin receptor activity can be very useful. After an initial evaluation by clinical history, urine analysis, and serological tests for celiac disease, gastroscopy and colonoscopy are the key diagnostic tools for investigating the origin of ID, and will detect the most important and prevalent diseases. If both tests are normal and anemia is not severe, treatment with oral iron can be indicated, along with stopping any treatment with non-steroidal anti-inflammatory drugs. In the absence of response to oral iron, or if the anemia is severe or clinical suspicion of important disease persists, we must insist on diagnostic evaluation. Repeat endoscopic studies should be considered in many cases and if both still show normal results, investigating the small bowel must be considered. The main techniques in this case are capsule endoscopy, followed by     

Role of new endoscopic techniques in inflammatory bowel disease management: Has the change come?

Despite significant therapeutic progress in recent years,inflammatory bowel disease(IBD),which includes Crohn’s disease and ulcerative colitis,remains a challenge regarding its pathogenesis and long-term complications.New concepts have emerged in the management of this disease,such as the"treat-totarget"concept,in which mucosal healing plays a key role in the evolution of IBD,the risk of recurrence and the need for surgery.Endoscopy is essential for the assessment of mucosal inflammation and plays a pivotal role in the analysis of mucosal healing in patients with IBD.Endoscopy is also essential in the detection of dysplasia and in the identification of the risk of colon cancer.The current surveillance strategy for dysplasia in IBD patients indicates white-light endoscopy with non-targeted biopsies.The new chromoendoscopy techniques provide substantial benefits for both clinicians and patients.Narrow-band imaging(NBI)has similar rates of dysplastic lesion detection as whitelight endoscopy,and it seems that NBI identifies more adenoma-like lesions.Because it is used instinctively by many endoscopists,the combination of these two techniques might improve the rate of dysplasia detection.Flexible spectral imaging color enhancement can help differentiate dysplastic and non-dysplastic lesions and can also predict the risk of recurrence,which allows us to modulate the treatment to gain better control of the disease.The combination of noninvasive serum and stool biomarkers with endoscopy will improve the monitoring and limit the evolution of IBD because it enables the use of a personalized approach to each patient based on that patient’s history and risk factors.     

Use of anesthesia on the rise in gastrointestinal endoscopy

Conscious sedation has been the standard of care for many years for gastrointestinal endoscopic procedures. As procedures have become more complex and lengthy, additional medications became essential for adequate sedation. Often time’s deep sedation is required for procedures such as endoscopic retrograde cholangiography which necessitates higher doses of narcotics and benzodiazepines or even use of other medications such as ketamine. Given its pharmacologic properties, pro-pofol was rapidly adopted worldwide to gastrointestinal endoscopy for complex procedures and more recently to routine upper and lower endoscopy. Many studies have shown superiority for both the physician and patient compared to standard sedation. Nevertheless, its use remains highly controversial. A number of studies worldwide show that propofol can be given safely by endoscopists or nurses when well trained. Despite this wealth of data, at many centers its use has been pro-hibited unless administered by anesthesiology. In this commentary, we review the use of anesthesia support for endoscopy in the United States based on recent data and its implications for gastroenterologists world-wide.     

Capsule endoscopy:Current practice and future directions

Capsule endoscopy(CE)has transformed investigation of the small bowel providing a non-invasive,well tolerated means of accurately visualising the distal duodenum,jejunum and ileum.Since the introduction of small bowel CE thirteen years ago a high volume of literature on indications,diagnostic yields and safety profile has been presented.Inclusion in national and international guidelines has placed small bowel capsule endoscopy at the forefront of investigation into suspected diseases of the small bowel.Most commonly,small bowel CE is used in patients with suspected bleeding or to identify evidence of active Crohn’s disease(CD)(in patients with or without a prior history of CD).Typically,CE is undertaken after upper and lower gastrointestinal flexible endoscopy has failed to identify a diagnosis.Small bowel radiology or a patency capsule test should be considered prior to CE in those at high risk of strictures(such as patients known to have CD or presenting with obstructive symptoms)to reduce the risk of capsule retention.CE also has a role in patients with coeliac disease,suspected small bowel tumours and other small bowel disorders.Since the advent of small bowel CE,dedicated oesophageal and colon capsule endoscopes have expanded the fields of application to include the investigation of upper and lower gastrointestinal disorders.Oesophageal CE may be used to diagnose oesophagitis,Barrett’s oesophagus and varices but reliability in identifying gastroduodenal pathology is unknown and it does not have biopsy capability.Colon CE provides an alternative to conventional colonoscopy for symptomatic patients,while a possible role in colorectal cancer screening is a fascinating prospect.Current research is already addressing the possibility of controlling capsule movement and developing capsules which allow tissue sampling and the administration of therapy.     

Clinical utility, safety and tolerability of capsule endoscopy in urban Southeast Asian population

AIM: Capsule endoscopy has demonstrated its clinical utility in the evaluation of small bowel pathology in several Western studies. In this prospective study, we aimed to determine the clinical utility, safety and tolerability of capsule endoscopy in the evaluation of suspected small bowel disease in an urban Southeast Asian population.METHODS: We used the given (M2A) capsule endoscopy system in 16 consecutive patients with suspected small bowel pathology. In 9 patients the indication was obscure gastrointestinal bleeding, while in 6 patients it was to determine the extent of small bowel involvement in Crohn‘s disease. One patient underwent capsule endoscopy for evaluation of chronic abdominal pain. Patient‘‘s tolerabilityto the procedure was evaluated by standardized questionnaires and all patients were reviewed at one week to ensure that the capsule had been excreted without any adverse events.RESULTS: Abnormal findings were present in 8 patients (50 %). The cause of obscure gastrointestinal bleeding was determined in 5 out of 9 patients. Findings included 2 cases of angiodysplasia, 2 cases of jejunal ulcers and 1 case of both angiodysplasia and jejunal ulcer. One patient had smallbowel erosions and foci of erythema of doubtful significance. Ileal lesions were diagnosed in 2 out of 6 patients with Crohn‘‘s disease. Capsule endoscopy was well tolerated by allpatients. One patient with Crohn‘‘s disease had a complication of capsule retention due to terminal ileum stricture. Thecapsule eventually passed out spontaneously after 1 month. CONCLUSION: Our study, which represented the first Asian series, further confirms the diagnostic utility, safety and tolerability of wireless capsule endoscopy.