Emerging technologies in upper gastrointestinal endoscopy and celiac disease. ACTA ACUST UNITED AC. 2009;6:47-56. [PMID: 19002131 DOI: 10.1038/ncpgasthep1298]

Updates in the diagnosis and management of coeliac disease

Coeliac disease is a common autoimmune disorder induced by ingesting gluten, the protein component of wheat, barley, and rye. It is estimated that one-in-hundred people worldwide have coeliac disease, of whom the majority remain undiagnosed. Coeliac disease is characterized by a wide range of gastrointestinal and extraintestinal symptoms but can also present asymptomatically. Diagnosing coeliac disease depends on the concordance of clinical, serological and histopathological data. However, the diagnosis can be challenging and frequently overlooked. Undiagnosed coeliac disease is associated with an increased risk of complications and detrimental effects on quality of life. Early diagnosis and treatment of coeliac disease are necessary to reduce the risk of long-term complications.

Gelatin-Based Ingestible Impedance Sensor to Evaluate Gastrointestinal Epithelial Barriers

Low-profile and transient ingestible electronic capsules for diagnostics and therapeutics can replace widely used yet invasive procedures such as endoscopies. Several gastrointestinal diseases such as reflux disease, Crohn's disease, irritable bowel syndrome, and eosinophilic esophagitis result in increased intercellular dilation in epithelial barriers. Currently, the primary method of diagnosing and monitoring epithelial barrier integrity is via endoscopic tissue biopsies followed by histological imaging. Here, a gelatin-based ingestible electronic capsule that can monitor epithelial barriers via electrochemical impedance measurements is proposed. Toward this end, material-specific transfer printing methodologies to manufacture soft-gelatin-based electronics, an in vitro synthetic disease model to validate impedance-based sensing, and tests of capsules using ex vivo using porcine esophageal tissue are described. The technologies described herein can advance next generation of oral diagnostic devices that reduce invasiveness and improve convenience for patients.

Guidelines of the Italian societies of gastroenterology on the diagnosis and management of coeliac disease and dermatitis herpetiformis

INTRODUCTION

Coeliac disease and dermatitis herpetiformis are immune-mediated diseases triggered by the consumption of gluten in genetically predisposed individuals. These guidelines were developed to provide general practitioners, paediatricians, gastroenterologists, and other clinicians with an overview on the diagnosis, management and follow-up of coeliac patients and those with dermatitis herpetiformis.

METHODS

Guidelines were developed by the Italian Societies of Gastroenterology. Following a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the certainty of the evidence. Statements and recommendations were developed by working groups consisting of gastroenterologists and a paediatrician with expertise in this field.

RESULTS

These guidelines provide a practical guidance for the diagnosis, management and follow-up of coeliac patients and dermatitis herpetiformis in children and adults, both in primary care and in specialist settings. We developed four sections on diagnosis, gluten-free diet, follow-up and risk of complications in adults, one section focused on diagnosis and follow-up in children and one on the diagnosis and management of dermatitis herpetiformis.

CONCLUSIONS

These guidelines may support clinicians to improve the diagnosis and management of patients with coeliac disease.

Position paper: The potential role of optical biopsy in the study and diagnosis of environmental enteric dysfunction

Environmental enteric dysfunction (EED) is a disease of the small intestine affecting children and adults in low and middle income countries. Arising as a consequence of repeated infections, gut inflammation results in impaired intestinal absorptive and barrier function, leading to poor nutrient uptake and ultimately to stunting and other developmental limitations. Progress towards new biomarkers and interventions for EED is hampered by the practical and ethical difficulties of cross-validation with the gold standard of biopsy and histology. Optical biopsy techniques - which can provide minimally invasive or noninvasive alternatives to biopsy - could offer other routes to validation and could potentially be used as point-of-care tests among the general population. This Consensus Statement identifies and reviews the most promising candidate optical biopsy technologies for applications in EED, critically assesses them against criteria identified for successful deployment in developing world settings, and proposes further lines of enquiry. Importantly, many of the techniques discussed could also be adapted to monitor the impaired intestinal barrier in other settings such as IBD, autoimmune enteropathies, coeliac disease, graft-versus-host disease, small intestinal transplantation or critical care.

Endoscopic evaluation of celiac disease severity and its correlation with histopathological aspects of the duodenal mucosa

BACKGROUND AND STUDY AIMS

Celiac disease (CD) is a chronic systemic autoimmune disorder affecting genetically predisposed individuals, triggered and maintained by the ingestion of gluten. Triggered and maintained by the ingestion of gluten, celiac disease is a chronic systemic autoimmune disorder affecting genetically predisposed individuals. Persistent related inflammation of the duodenal mucosa causes atrophy architecture detectable on esophagogastroduodenoscopy (EGD) and histopathology. We investigated the association between endoscopic features and histopathological findings (Marsh) for duodenal mucosa in celiac disease patients and propose an endoscopic classification of severity.

PATIENTS AND METHODS

Between January 2000 and March 2010, an electronic database containing 34,540 EDGs of patients aged > 14 years was searched for cases of CD. Out of 109 cases, 85 met the inclusion criteria: conventional EGD combined with chromoendoscopy, zoom and biopsy. EGD types 0, I and II corresponds to Marsh grades 0, 1 and 2, respectively, while EGD type III corresponds to Marsh grade 3 and 4.

RESULTS

Five patients (5.8 %) were EGD I but not Marsh grade 1; 25 patients (29.4 %) were EGD II, 4 of whom (16 %) were classified as Marsh grade 2; and 55 patients (64.7 %) were EGD III, 51 (92.7 %) of whom were classified as Marsh grades 3 and 4. The Spearman correlation coefficient (r = 0.33) revealed a significant association between the methods (P = 0.002).

CONCLUSIONS

Changes in the duodenal mucosa detected on EGD were significantly and positively associated with histopathologic findings. The use of chromoendoscopy in addition to conventional EGD enhances changes in the duodenal mucosa and permits diagnosis of CD, even in routine examinations. The proposed endoscopic classification is practical and easily reproducible and provides valuable information regarding disease extension.

Diagnostic yield of endoscopic markers for celiac disease

RATIONALE

In the setting of open access endoscopy, the recognition of suggestive endoscopic features in the duodenum can select patients with probability of celiac disease (CD). This could add to the current efforts to increase the diagnostic rate of this disease.

AIM

The aim of this study was to evaluate the diagnostic accuracy of these markers for CD in an adult population undergoing endoscopy, without a prior serological testing.

METHODS AND RESULTS

Over a period of 3 years, between June 2012 and 2015, all the patients who underwent upper gastrointestinal endoscopy and presented one or more of the endoscopic markers consistent with CD, or those suspected for CD, irrespective of the presence of these markers, were included. Sensitivity, specificity, positive and negative predictive values were calculated for these markers in CD diagnosis. Among the 182 patients, 56.04% were females, with a mean age of 47.6 ± 13.9 years. 20/182 (10.99%) had a final diagnosis of CD. The presence of any endoscopic marker had a high sensitivity (95%) and a negative predictive value (98.41%). Bulb atrophy and reduced folds in the descending duodenum had a low diagnostic accuracy, while scalloping, mosaic pattern and fissures were highly specific for CD (98.77%, 99.38% and 98.77%) and their presence greatly increased the probability of CD, with a positive likelihood ratio of 24.3, 24.3 and 12.15, respectively.

DISCUSSIONS

A wide set of endoscopic markers, including the duodenal bulb, were evaluated in this study. Our results showed that the endoscopy with a careful examination of the duodenum is a sensitive indicator for CD.

ABBREVIATIONS

CD = celiac disease, GI = gastrointestinal, VA = villous atrophy, NSAID = nonsteroidal anti-inflammatory drug, Sn = sensitivity, Sp = specificity, PPV = positive predictive value, NPV = negative predictive value, AUC = area under the curve, ROC = receiver operating characteristics, WLE = white light endoscopy, NBI = narrow band imaging, tTG = tissue transglutaminase, EMA = anti-endomysial antibodies.

Enteroscopic findings of Celiac Disease and their correlation with mucosal histopathologic changes

BACKGROUND AND AIMS

Single Balloon Enteroscopy enables us to examine the small bowel for various diseases. It provides a view of the intestinal mucosa with biopsy capability, which may be helpful in search of a mucosal disease such as Celiac Disease. Celiac Disease is a proximal enteropathy developed in genetically susceptible individuals to wheat protein gluten. Examination of the duodenum and proximal jejunum are mostly diagnostic. We aimed to review enteroscopic findings of the patients with Celiac Disease.

PATIENTS AND METHODS

Consecutive adult patients (>18y) who needed intestinal or duodenal biopsy for the diagnosis of the Celiac Disease were included. Single Balloon Enteroscopy system was used to enter the proximal jejunum. All of the patients had biopsies in order to diagnose Celiac Disease.

RESULTS

Single Balloon Enteroscopy was performed in 33 patients. Twenty two (66.7%) subjects were diagnosed as Celiac Disease. The most common endoscopic abnormality in Celiac Disease was mucosal atrophy in 20 patients (90.9%), continuous involvement was the most common presentation (36.4%). All of the patients with Celiac Disease exhibited at least one endoscopic change.

CONCLUSIONS

This study confirmed the patchy nature of the disease with mostly diffuse involvement of the small bowel. However, any endoscopic abnormality can be found in every patient with Celiac Disease. Analysis of images from either conventional upper endoscopy or capsule endoscopy may aid the diagnosis.

Correlation of endoscopic and histological features in adults with suspected celiac disease in a referral center of Minas Gerais, Brazil

CONTEXT

Clinical presentation of celiac disease is extremely variable and the diagnosis relies on serologic tests, mucosal intestinal biopsy and clinic and serologic response to a gluten-free diet.

OBJECTIVES

To correlate the endoscopic and histological aspects of adult patients with suspicion of celiac disease and to evaluate the interobserver histological agreement.

METHODS

Endoscopic aspects of 80 adult patients were evaluated and correlated with the histological features according the Marsh-Oberhuber classification system. The interobserver histological agreement was based on kappa values.

RESULTS

The symptoms of the patients varied largely, with prominence for chronic diarrhea, present in 48 (60%) patients. The endoscopic aspects related with the duodenal villous atrophy had been observed in 32 (40%) patients. There were confirmed 46 cases of celiac disease, with prevalence of 57.5%. The sensitivity, specificity, positive predictive value and negative predictive value of the endoscopic markers for celiac disease diagnosis were of 60.9%, 88.2%, 87.5% and 62.5%. There was moderate interobserver histological agreement (kappa = 0.46).

CONCLUSIONS

The endoscopic markers of villous atrophy, although not diagnostic, had assisted in the suspicion and indication of the duodenal biopsies for diagnosis proposal. Histology is sometimes contradictory and new biopsies or opinion of another professional can provide greater diagnostic agreement.

Narrow band imaging combined with water immersion technique in the diagnosis of celiac disease

BACKGROUND

The "multiple-biopsy" approach both in duodenum and bulb is the best strategy to confirm the diagnosis of celiac disease; however, this increases the invasiveness of the procedure itself and is time-consuming.

AIM

To evaluate the diagnostic yield of a single biopsy guided by narrow-band imaging combined with water immersion technique in paediatric patients.

METHODS

Prospective assessment of the diagnostic accuracy of narrow-band imaging/water immersion technique-driven biopsy approach versus standard protocol in suspected celiac disease.

RESULTS

The experimental approach correctly diagnosed 35/40 children with celiac disease, with an overall diagnostic sensitivity of 87.5% (95% CI: 77.3-97.7). An altered pattern of narrow-band imaging/water immersion technique endoscopic visualization was significantly associated with villous atrophy at guided biopsy (Spearman Rho 0.637, p<0.001). Concordance of narrow-band imaging/water immersion technique endoscopic assessments was high between two operators (K: 0.884). The experimental protocol was highly timesaving compared to the standard protocol.

CONCLUSIONS

An altered narrow-band imaging/water immersion technique pattern coupled with high anti-transglutaminase antibodies could allow a single guided biopsy to diagnose celiac disease. When no altered mucosal pattern is visible even by narrow-band imaging/water immersion technique, multiple bulbar and duodenal biopsies should be obtained.

Duodenal villous morphology assessed using magnification narrow band imaging correlates well with histology in patients with suspected malabsorption syndrome

BACKGROUND AND AIM

Narrow band imaging with magnification enables detailed assessment of duodenal villi and may be useful in predicting the presence of villous atrophy or normal villi. We aimed to assess the morphology of duodenal villi using magnification narrow band imaging and correlate it with histology findings in patients with clinically suspected malabsorption syndrome.

METHODS

Patients with clinical suspicion of malabsorption presenting at a tertiary care center were prospectively recruited in this diagnostic intervention study. Patients underwent upper gastrointestinal endoscopy using magnification narrow band imaging. The villous morphology in the second part of the duodenum was assessed independently by two endoscopists and the presence of normal or atrophic villi was recorded. Biopsy specimen was obtained from the same area and was examined by two pathologists together. The sensitivity and specificity of magnification narrow band imaging in detecting the presence of duodenal villous atrophy was calculated and compared to the histology.

RESULTS

One hundred patients with clinically suspected malabsorption were included in this study. Sixteen patients had histologically confirmed villous atrophy. The sensitivity and specificity of narrow band imaging in predicting villous atrophy was 87.5% and 95.2%, respectively, for one endoscopist. The corresponding figures for the second endoscopist were 81.3% and 92.9%, respectively. The interobserver agreement was very good with a kappa value of 0.87.

CONCLUSION

Magnification narrow band imaging performed very well in predicting duodenal villous morphology. This may help in carrying out targeted biopsies and avoiding unnecessary biopsies in patients with suspected malabsorption.

Diagnosis and management of adult coeliac disease: guidelines from the British Society of Gastroenterology

A multidisciplinary panel of 18 physicians and 3 non-physicians from eight countries (Sweden, UK, Argentina, Australia, Italy, Finland, Norway and the USA) reviewed the literature on diagnosis and management of adult coeliac disease (CD). This paper presents the recommendations of the British Society of Gastroenterology. Areas of controversies were explored through phone meetings and web surveys. Nine working groups examined the following areas of CD diagnosis and management: classification of CD; genetics and immunology; diagnostics; serology and endoscopy; follow-up; gluten-free diet; refractory CD and malignancies; quality of life; novel treatments; patient support; and screening for CD.

Celiac disease or non-celiac gluten sensitivity? An approach to clinical differential diagnosis

OBJECTIVES

Differentiating between celiac disease (CD) and non-celiac gluten sensitivity (NCGS) is important for appropriate management but is often challenging.

METHODS

We retrospectively reviewed records from 238 patients who presented for the evaluation of symptoms responsive to gluten restriction without prior diagnosis or exclusion of CD. Demographics, presenting symptoms, serologic, genetic, and histologic data, nutrient deficiencies, personal history of autoimmune diseases, and family history of CD were recorded. NCGS was defined as symptoms responsive to a gluten-free diet (GFD) in the setting of negative celiac serology and duodenal biopsies while on a gluten-containing diet or negative human leukocyte antigen (HLA) DQ2/DQ8 testing.

RESULTS

Of the 238 study subjects, 101 had CD, 125 had NCGS, 9 had non-celiac enteropathy, and 3 had indeterminate diagnosis. CD subjects presented with symptoms of malabsorption 67.3% of the time compared with 24.8% of the NCGS subjects (P<0.0001). In addition, CD subjects were significantly more likely to have a family history of CD (P=0.004), personal history of autoimmune diseases (P=0.002), or nutrient deficiencies (P<0.0001). The positive likelihood ratio for diagnosis of CD of a >2× upper limit of normal IgA trans-glutaminase antibody (tTG) or IgA/IgG deaminated gliadan peptide antibody (DGP) with clinical response to GFD was 130 (confidence interval (CI): 18.5-918.3). The positive likelihood ratio of the combination of gluten-responsive symptoms and negative IgA tTG or IgA/IgG DGP on a regular diet for NCGS was 9.6 (CI: 5.5-16.9). When individuals with negative IgA tTG or IgA/IgG DGP also lacked symptoms of malabsorption (weight loss, diarrhea, and nutrient deficiencies) and CD risk factors (personal history of autoimmune diseases and family history of CD), the positive likelihood ratio for NCGS increased to 80.9.

CONCLUSIONS

On the basis of our findings, we have developed a diagnostic algorithm to differentiate CD from NCGS. Subjects with negative celiac serologies (IgA tTG or IgA/IgG DGP) on a regular diet are unlikely to have CD. Those with negative serology who also lack clinical evidence of malabsorption and CD risk factors are highly likely to have NCGS and may not require further testing. Those with equivocal serology should undergo HLA typing to determine the need for biopsy.

Gastro 2013 APDW/WCOG Shanghai working party report: chronic diarrhea: definition, classification, diagnosis

Diarrhea is best defined as passage of loose stools often with more frequent bowel movements. For clinical purposes, the Bristol Stool Form Scale works well to distinguish stool form and to identify loose stools. Laboratory testing of stool consistency has lagged behind. Acute diarrhea is likely to be due to infection and to be self-limited. As diarrhea becomes chronic, it is less likely to be due to infection; duration of 1 month seems to work well as a cut-off for chronic diarrhea, but detailed scientific knowledge is missing about the utility of this definition. In addition to duration of diarrhea, classifications by presenting scenario, by pathophysiology, and by stool characteristics (e.g. watery, fatty, or inflammatory) may help the canny clinician refine the differential diagnosis of chronic diarrhea. In this regard, a careful history remains the essential part of the evaluation of a patient with diarrhea. Imaging the intestine with endoscopy and radiographic techniques is useful, and biopsy of the small intestine and colon for histological assessment provides key diagnostic information. Endomicroscopy and molecular pathology are only now being explored for the diagnosis of chronic diarrhea. Interest in the microbiome of the gut is increasing; aside from a handful of well-described infections because of pathogens, little is known about alterations in the microbiome in chronic diarrhea. Serological tests have well-defined roles in the diagnosis of celiac disease but have less clearly defined application in autoimmune enteropathies and inflammatory bowel disease. Measurement of peptide hormones is of value in the diagnosis and management of endocrine tumors causing diarrhea, but these are so rare that these tests are of little value in screening because there will be many more false-positives than true-positive results. Chemical analysis of stools is of use in classifying chronic diarrhea and may limit the differential diagnosis that must be considered, but interpretation of the results is still evolving. Breath tests for assessment of carbohydrate malabsorption, small bowel bacterial overgrowth, and intestinal transit are fraught with technical limitations that decrease sensitivity and specificity. Likewise, tests of bile acid malabsorption have had limited utility beyond empirical trials of bile acid sequestrants.

Endoscopic tools for the diagnosis and evaluation of celiac disease

Celiac disease (CD) is an autoimmune disease of the small bowel induced by ingestion of wheat, rye and barley. Current guidelines indicate histological analysis on at least four duodenal biopsies as the only way to diagnose CD. These indications are based on the conception of the inability of standard endoscopy to make diagnosis of CD and/or to drive biopsy sampling. Over the last years, technology development of endoscopic devices has greatly ameliorated the accuracy of macroscopic evaluation of duodenal villous pattern, increasing the diagnostic power of endoscopy of CD. The aim of this paper is to review the new endoscopic tools and procedures proved to be useful in the diagnosis of CD, such as chromoendoscopy, Fujinon Intelligent Chromo Endoscopy, Narrow Band Imaging, Optical Coherence Tomography, Water-Immersion Technique, confocal laser endomicroscopy, high-resolution magnification endoscopy, capsule endoscopy and I-Scan technology.

Veterinary and human biobanking practices: enhancing molecular sample integrity

Animal models have historically informed veterinary and human pathophysiology. Next-generation genomic sequencing and molecular analyses using analytes derived from tissue require integrative approaches to determine macroanalyte integrity as well as morphology for imaging algorithms that can extend translational applications. The field of biospecimen science and biobanking will play critical roles in tissue sample collection and processing to ensure the integrity of macromolecules, aid experimental design, and provide more accurate and reproducible downstream genomic data. Herein, we employ animal experiments to combine protein expression analysis by microscopy with RNA integrity number and quantitative measures of morphologic changes of autolysis. These analyses can be used to predict the effect of preanalytic variables and provide the basis for standardized methods in tissue sample collection and processing. We also discuss the application of digital imaging with quantitative RNA and tissue-based protein measurements to show that genomic methods augment traditional in vivo imaging to support biospecimen science. To make these observations, we have established a time course experiment of murine kidney tissues that predicts conventional measures of RNA integrity by RIN analysis and provides reliable and accurate measures of biospecimen integrity and fitness, in particular for time points less than 3 hours post-tissue resection.

Use of shape-from-shading to estimate three-dimensional architecture in the small intestinal lumen of celiac and control patients

BACKGROUND

As measured from videocapsule endoscopy images, the small intestinal mucosa of untreated celiac patients has significantly greater and more varied texture compared to normal patients. Three-dimensional modeling using shape-from-shading principles may further increase classification accuracy.

METHODS

A sequence of 200 consecutive videocapsule images acquired at a 2s(-1) frame rate and 576×576 pixel dimension, were obtained at four locations in the small intestinal lumen of ten patients with biopsy-proven celiac disease and ten control patients. Each two-dimensional image was converted to a three-dimensional architectural approximation by considering the 256 grayscale level to be linearly representative of image depth. From the resulting three-dimensional architecture, distinct luminal protrusions, representative of the macro-architecture, were automatically identified by computer algorithm. The range and number of protrusions per image, and their width and height, were determined for celiacs versus controls and tabulated as mean±SD.

RESULTS

The mean number of villous protrusions per image was 402.2±15.0 in celiacs versus 420.8±24.0 in controls (p<0.001). The average protrusion width was 14.7 pixels in celiacs versus 13.9 pixels in controls (p=0.01). The mean protrusion height was 3.10±2.34 grayscale levels for celiacs versus 2.70±0.43 grayscale levels for controls (p<0.001). Thus celiac patients had significantly fewer protrusions on the luminal surface of the small intestine as compared with controls, and these protrusions had greater dimensions, suggesting they are indicative of a mosaic (cobblestone) macro-architectural pattern which is common in celiacs.

CONCLUSIONS

Shape-from-shading modeling is useful to explore luminal macro-architecture and to detect significant differences in luminal morphology in celiac versus normal patients, which can increase the usefulness of videocapsule studies.

Narrow band imaging with magnification endoscopy for celiac disease: results from a prospective, single-center study

In celiac disease (CD), the intestinal lesions can be patchy and partial villous atrophy may elude detection at standard endoscopy (SE). Narrow Band Imaging (NBI) system in combination with a magnifying endoscope (ME) is a simple tool able to obtain targeted biopsy specimens. The aim of the study was to assess the correlation between NBI-ME and histology in CD diagnosis and to compare diagnostic accuracy between NBI-ME and SE in detecting villous abnormalities in CD. Forty-four consecutive patients with suspected CD undergoing upper gastrointestinal endoscopy have been prospectively evaluated. Utilizing both SE and NBI-ME, observed surface patterns were compared with histological results obtained from biopsy specimens using the k-Cohen agreement coefficient. NBI-ME identified partial villous atrophy in 12 patients in whom SE was normal, with sensitivity, specificity, and accuracy of 100%, 92.6%, and 95%, respectively. The overall agreement between NBI-ME and histology was significantly higher when compared with SE and histology (kappa score: 0.90 versus 0.46; P = 0.001) in diagnosing CD. NBI-ME could help identify partial mucosal atrophy in the routine endoscopic practice, potentially reducing the need for blind biopsies. NBI-ME was superior to SE and can reliably predict in vivo the villous changes of CD.

Image-enhanced endoscopy with I-scan technology for the evaluation of duodenal villous patterns

BACKGROUND

I-scan technology is the newly developed endoscopic tool that works in real time and utilizes a digital contrast method to enhance endoscopic image.

AIMS

We performed a feasibility study aimed to determine the diagnostic accuracy of i-scan technology for the evaluation of duodenal villous patterns, having histology as the reference standard.

METHODS

In this prospective, single center, open study, patients undergoing upper endoscopy for an histological evaluation of duodenal mucosa were enrolled. All patients underwent upper endoscopy using high resolution view in association with i-scan technology. During endoscopy, duodenal villous patterns were evaluated and classified as normal, partial villous atrophy, or marked villous atrophy. Results were then compared with histology.

RESULTS

One hundred fifteen subjects were recruited in this study. The endoscopist was able to find marked villous atrophy of the duodenum in 12 subjects, partial villous atrophy in 25, and normal villi in the remaining 78 individuals. The i-scan system was demonstrated to have great accuracy (100 %) in the detection of marked villous atrophy patterns. I-scan technology showed quite lower accuracy in determining partial villous atrophy or normal villous patterns (respectively, 90 % for both items).

CONCLUSIONS

Image-enhancing endoscopic technology allows a clear visualization of villous patterns in the duodenum. By switching from the standard to the i-scan view, it is possible to optimize the accuracy of endoscopy in recognizing villous alteration in subjects undergoing endoscopic evaluation.

Image-enhanced endoscopy with I-scan technology for the evaluation of duodenal villous patterns

BACKGROUND

I-scan technology is the newly developed endoscopic tool that works in real time and utilizes a digital contrast method to enhance endoscopic image.

AIMS

We performed a feasibility study aimed to determine the diagnostic accuracy of i-scan technology for the evaluation of duodenal villous patterns, having histology as the reference standard.

METHODS

In this prospective, single center, open study, patients undergoing upper endoscopy for an histological evaluation of duodenal mucosa were enrolled. All patients underwent upper endoscopy using high resolution view in association with i-scan technology. During endoscopy, duodenal villous patterns were evaluated and classified as normal, partial villous atrophy, or marked villous atrophy. Results were then compared with histology.

RESULTS

One hundred fifteen subjects were recruited in this study. The endoscopist was able to find marked villous atrophy of the duodenum in 12 subjects, partial villous atrophy in 25, and normal villi in the remaining 78 individuals. The i-scan system was demonstrated to have great accuracy (100 %) in the detection of marked villous atrophy patterns. I-scan technology showed quite lower accuracy in determining partial villous atrophy or normal villous patterns (respectively, 90 % for both items).

CONCLUSIONS

Image-enhancing endoscopic technology allows a clear visualization of villous patterns in the duodenum. By switching from the standard to the i-scan view, it is possible to optimize the accuracy of endoscopy in recognizing villous alteration in subjects undergoing endoscopic evaluation.

Difficult diagnosis of celiac disease: diagnostic accuracy and utility of chromo-zoom endoscopy

BACKGROUND

Chromo-zoom endoscopy has been demonstrated to be valuable in assessing the degree of intestinal villous atrophy in patients with suspected celiac disease.

OBJECTIVE

To evaluate the diagnostic accuracy of chromo-zoom endoscopy in patients with difficult diagnosis because of nonconcordant test results and/or the confounding of a gluten-free diet initiated before an appropriate diagnosis of celiac disease and to compare the findings to a recent reference standard, the in vitro gliadin challenge test.

DESIGN

Prospective, case-control study.

SETTING

Tertiary-care referral hospital.

PATIENTS

Patients without celiac disease (negative control group, n = 9), patients with celiac disease (positive control group, n = 41), and patients with difficult diagnosis (n = 27).

INTERVENTION

Chromo-endoscopy with indigo carmine and endoscopic zoom-magnification were performed. Duodenal fragments were collected for the in vitro gliadin challenge test. The area under the receiver operating characteristic curve (ROC) was used for statistical analyses on accuracy.

MAIN OUTCOME MEASUREMENTS

Diagnostic accuracy of chromo-zoom endoscopy for detection of mucosal abnormalities in patients with difficult diagnosis.

RESULTS

Chromo-zoom endoscopy had a high accuracy for celiac disease diagnosis in analyses on negative controls and positive controls (area under roc = 0.99). In the difficult diagnosis group, the accuracy of chromo-zoom endoscopy was lower (area under roc = 0.83), but it increased after exclusion of patients with celiac disease on gluten-free diet (area under roc = 0.88).

LIMITATIONS

There was a 4% failure rate in the ability to cultivate biopsies. Also, the study was done at an academic medical center.

CONCLUSION

Chromo-zoom endoscopy has high accuracy for cases of difficult diagnosis of celiac disease but only in untreated patients with celiac disease.

Is enteroscopy necessary for diagnosis of celiac disease?

Celiac disease (CD) is an autoimmune inflammatory disease of the small intestine as a result of reaction to wheat protein, gluten. Exclusion of dietary gluten is the mainstay of the treatment that necessitates a precise diagnosis of the disease. Serological screening may aid in identifying patients with suspected CD, which should be confirmed by intestinal biopsy. It has been shown that duodenal biopsies are good for detection of the disease in most patients. However, there is a group of patients with positive serology and inconclusive pathology. As a result of the widespread use of serology, many patients with equivocal findings grow quickly. Unfortunately current endoscopic methods can only diagnose villous atrophy, which can be present in the later grades of disease (i.e., Marsh III). To diagnose CD correctly, going deeper in the intestine may be necessary. Enteroscopy can reveal changes in CD in the intestinal mucosa in 10%-17% of cases that have negative histology at initial workup. Invasiveness of the method limits its use. Capsule endoscopy may be a good substitute for enteroscopy. However, both techniques should be reserved for patients with suspected diagnosis of complications. This paper reviews the current literature in terms of the value of enteroscopy for diagnosis of CD.

Update on celiac disease - etiology, differential diagnosis, drug targets, and management advances

Celiac disease (CD) is an immune-mediated enteropathy triggered by exposure to wheat gluten and similar proteins found in rye and barley that affects genetically susceptible persons. This immune-mediated enteropathy is characterized by villous atrophy, intraepithelial lymphocytosis, and crypt hyperplasia. Once thought a disease that largely presented with malnourished children, the wide spectrum of disease activity is now better recognized and this has resulted in a shift in the presenting symptoms of most patients with CD. New advances in testing, both serologic and endoscopic, have dramatically increased the detection and diagnosis of CD. While the gluten-free diet is still the only treatment for CD, recent investigations have explored alternative approaches, including the use of altered nonimmunogenic wheat variants, enzymatic degradation of gluten, tissue transglutaminase inhibitors, induction of tolerance, and peptides to restore integrity to intestinal tight junctions.

An update in the diagnosis of coeliac disease

Coeliac disease is increasing in prevalence, which is currently estimated at one in 100 of the population and may occur de novo in adults. The diagnosis requires a joint clinicopathological approach; the recommended first-line test is serology with immunoglobulin A (IgA) tissue transglutaminase and IgA endomysial antibodies. These serological tests show high levels of sensitivity and specificity, but biopsy is the gold standard to confirm the diagnosis. It is important that both tests are performed before the introduction of a gluten-free diet. Although the classical histopathology changes of coeliac disease with partial or total villous atrophy are well recognized, the pathology classification of coeliac disease is changing, with recognition that coeliac disease may show minimal pathology (normal architecture and an intraepithelial lymphocyte count/100 enterocytes ≥ 25). This entity is also described as lymphocytic duodenosis, and recommendation of follow-up serology testing is paramount in this condition. Follow-up of patients with coeliac disease is warranted, as normal serology does not predict mucosal recovery. Failure to heal predicts risk of progression to refractory coeliac disease and malignancies. Refractory coeliac disease occurs in 1-2% of patients and this diagnosis requires a combined clinical and histopathology approach with immunocytochemistry.

Indian task force for celiac disease: Current status

There are limited data on celiac disease (CD) from India. The limited knowledge about CD in India might be attributed to several factors. The first meeting of the Indian Task Force for Celiac Disease was held in the Asian Institute of Gastroenterology, Hyderabad, India in December 2008. The objectives of the meeting were to focus research on prevalence of CD in the wheat-eating Northern vs the rice-eating Southern Indian population, low-budget serological assays to study the underprivileged population, to involve other medical subspecialties in CD, to suggest proper legislation regarding wheat food labeling, and to organize affordable food substitutes for patients with celiac disease.

Enteroscopy in the diagnosis and management of celiac disease

Esophagogastroduodenoscopy (EGD) with 3 to 6 biopsies in the descending duodenum is the gold standard for the diagnosis of celiac disease. At the time of the first diagnosis of celiac disease, an extensive evaluation of the small bowel is not recommended. However, video capsule endoscopy, because of its good sensitivity and specificity in recognizing the Endoscopic features of celiac disease, can be considered a valid alternative to EGD in patients unable or unwilling to undergo EGD with biopsies. Capsule endoscopy is also a possible option in selected cases with strong suspicion of celiac disease but negative first-line tests. In evaluating patients with refractory or complicated celiac disease, in whom a complete evaluation of the small bowel is mandatory (at least in refractory celiac disease type II patients) because of the possible presence of complications beyond the reach of conventional endoscopes, both capsule endoscopy and balloon-assisted enteroscopy have been found to be helpful. In these patients, capsule endoscopy offers several advantages: it is well tolerated, it allows inspection of the entire small bowel, and it is able to recognize subtle mucosal changes. However, in this setting, capsule endoscopy should ideally be coupled with imaging techniques that provide important information about the thickness of the wall of the intestine and about extraluminal abnormalities. Although deep enteroscopy (such as balloon enteroscopy) is expensive, time-consuming, and potentially risky in these frail patients, they may have a key role, because they make it possible to take tissue samples from deep in the small intestine.

Celiac Disease in the 21st Century: Issues of Under-and Over-Diagnosis

Until the 1960s celiac disease (CD) or sprue was considered a pediatric disease that was rarely diagnosed in adulthood. Thanks to greater awareness of the disease and the availability of improved diagnostic tools (above all, sophisticated endoscopic techniques and the development of reliable serological markers), the prevalence of CD in Western countries has been increasing steadily, and it is now recognized as a common disorder, even in adults. However, many cases of this disease still go undiagnosed, especially among the elderly and in patients with atypical clinical presentations (which are by no means uncommon). On the other hand, the frequency of unfounded diagnoses of CD is also on the rise. This reflects a tendency toward exclusively symptomatic diagnosis as well as the growing use of invalidated tests for CD (e.g., the cytotoxic test, the sublingual or subcutaneous provocation/neutralization test, etc.). As a result, public healthcare spending is being increased in several countries (Italy included) by the growing number of prescriptions for gluten-free diets. This editorial discusses the problems of under- and over-diagnosis of CD and provides an algorithm for management of suspected cases designed to minimize both problems with particular importance to morphologic aspects of small bowel (also in electron microscopy), in basal conditions or in gluten-free diets.