Comparison of suction capsule and endoscopic biopsy of small bowel mucosa

Review article: Current status and future directions of ingestible electronic devices in gastroenterology

BACKGROUND

Advances in microelectronics have greatly expanded the capabilities and clinical potential of ingestible electronic devices.

AIM

To provide an overview of the structure and potential impact of ingestible devices in development that are relevant to the gastrointestinal tract.

METHODS

We performed a detailed literature search to inform this narrative review.

RESULTS

Technical success of ingestible electronic devices relies on the ability to miniaturise the microelectronic circuits, sensors and components for interventional functions while being sufficiently powered to fulfil the intended function. These devices offer the advantages of being convenient and minimally invasive, with real-time assessment often possible and with minimal interference to normal physiology. Safety has not been a limitation, but defining and controlling device location in the gastrointestinal tract remains challenging. The success of capsule endoscopy has buoyed enthusiasm for the concepts, but few ingestible devices have reached clinical practice to date, partly due to the novelty of the information they provide and also due to the challenges of adding this novel technology to established clinical paradigms. Nonetheless, with ongoing technological advancement and as understanding of their potential impact emerges, acceptance of such technology will grow. These devices have the capacity to provide unique insight into gastrointestinal physiology and pathophysiology. Interventional functions, such as sampling of tissue or luminal contents and delivery of therapies, may further enhance their ability to sharpen gastroenterological diagnoses, monitoring and treatment.

CONCLUSIONS

The development of miniaturised ingestible microelectronic-based devices offers exciting prospects for enhancing gastroenterological research and the delivery of personalised, point-of-care medicine.

Coeliac disease in childhood: An overview

Coeliac disease (CD) is an autoimmune condition, characterised by an immunological response to ingestion of gluten in genetically susceptible individuals, affecting about 1% of the population in many regions of the world. Increased knowledge regarding the pathogenesis, improved diagnostic techniques and increased awareness over the years have transformed our understanding of CD such that it is no longer a rare enteropathy, but rather a common multisystem disorder which affects individuals of all ages and results in wide-ranging clinical manifestations. Only a minority of children now present with the classical clinical picture of profound diarrhoea and malnutrition. An increasing number of children with CD present with either mild, non-specific gastrointestinal symptoms or extra-intestinal manifestations or even be asymptomatic, as in many screening-detected children. Knowledge about these diverse manifestations and a high index of suspicion is essential so that appropriate investigations can be undertaken, diagnosis established and treatment initiated. Although traditionally small bowel biopsy is considered essential for the diagnosis, recent guidelines from various professional bodies have paved the way to a biopsy-free diagnosis in a subset of symptomatic children. Life long, strict gluten-free diet still remains the only effective treatment at present, although several novel therapeutic agents are in various phases of clinical trials.

Narrow-band imaging with magnification and the water immersion technique: a case-finding, cost-effective approach to diagnose villous atrophy

INTRODUCTION

Narrow-band imaging with magnification endoscopy (NBI-ME) allows real-time visual assessment of the mucosal surface and vasculature of the gastrointestinal tract. This study aimed to determine the performance of NBI-ME combined with the water immersion technique (NBI-ME-WIT) in detecting villous atrophy.

METHODS

All patients who underwent gastroscopy were included. The duodenum was further examined with NBI-ME-WIT only after examination with white light endoscopy did not reveal a cause of anaemia or dyspepsia. Targeted biopsies were taken of visualised areas. NBI-ME-WIT findings were compared with the final histopathological analysis. We calculated the sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of NBI-ME-WIT in detecting villous atrophy and the hypothetical cost saved by using a biopsy-avoiding approach.

RESULTS

124 patients (83 female) with a mean age of 46 (range 18-82) years were included. The most common indication for gastroscopy was abdominal pain (39%), followed by anaemia (35%), chronic diarrhoea/altered bowel habits (19%) and dyspepsia (6%). NBI-ME-WIT was able to detect all nine patients with villous atrophy - eight patchy and one total villous atrophy. The Sn, Sp, PPV and NPV of NBI-ME-WIT in detecting villous atrophy were 100.0%, 99.1%, 90.0% and 100.0%, respectively. Taking into account the cost of biopsy forceps (AUD 17) and pathology (AUD 140), this biopsy-avoidance strategy could have saved AUD 18,055 in these patients.

CONCLUSION

NBI-ME-WIT is a specific and sensitive tool to recognise and accurately diagnose villous atrophy. Biopsies can be avoided in patients with normal-sized villi, which may decrease the overall cost of the procedure.

Celiac Disease: Updates on Pathology and Differential Diagnosis

Celiac disease is a gluten-triggered immune-mediated disorder, characterized by inflammation of the enteric mucosa following lymphocytic infiltration and eventually resulting in villous blunting. There have been many developments in refining diagnostic laboratory tests for celiac disease in the last decade. Biopsy-sparing diagnostic guidelines have been proposed and validated in a few recent prospective studies. However, despite these developments, histologic evaluation of duodenal mucosa remains one of the most essential diagnostic tools as it helps in the diagnosis of celiac disease in individuals who do not fulfill the biopsy-sparing diagnostic criteria and in those not responding to a gluten-free diet. Histologic evaluation also allows for the assessment of mucosal recovery after treatment and in the identification of concurrent intestinal diseases. Therefore, pathologists should be familiar with the histologic spectrum of celiac disease and need to be aware of other disorders with similar symptoms and histopathology that may mimic celiac disease. This review aims to provide pathologists with updates on celiac laboratory testing, biopsy-sparing diagnostic criteria, histopathology, complications, and differential diagnoses of celiac disease.

A prospective study to evaluate the role of duodenal bulb biopsy in the diagnosis of celiac disease

BACKGROUND

Celiac disease (CeD) requires a biopsy from the small intestine to confirm the diagnosis. Conventionally, duodenal bulb (D1) was avoided as a biopsy site due to histological confounding factors at this site. However, sometimes, the bulb mucosa is the only affected site. The aim of the present study was to assess changes in duodenal bulb histology and compare it to distal duodenal histology and to analyze whether the addition of duodenal bulb biopsy increases the diagnostic yield of the CeD.

METHODS

It was a prospective study comprising of 98 patients of CeD who were symptomatic clinically and had positive anti tissue transglutaminase (tTG) antibody. Endoscopically four mucosal biopsies were taken, two each from the bulb and distal duodenum, and morphology was graded as per modified Marsh grade.

RESULTS

Iron deficiency anemia (40%) was a most common clinical presentation followed by chronic diarrhea (30%). Sixty patients showed same Marsh grade and 38 showed different Marsh grade at both sites. Patients who were showing the difference in the Marsh grade at the two biopsy sites, in place of; descending duodenum showed higher grade in 24 patients while higher mucosal atrophy was documented in the bulb in 14 patients. No patient of CeD had isolated D1 involvement. In eight patients, the correct diagnosis of CeD could be made only because of bulb biopsy.

CONCLUSION

Majority of the patients had no classical symptoms. Different Marsh grade at the two biopsy sites was documented demonstrating the patchy distribution of CeD. Combining biopsy from both bulb and descending duodenum maximizes the diagnostic yield of the CeD.

Non-endoscopic biopsy techniques: a review

Diseases of the stomach and small intestine account for approximately 20% of all gastrointestinal (GI)-related mortality. Biopsy of the stomach and small intestine remains a key diagnostic tool for most of the major diseases that affect the GI tract. While endoscopic means for obtaining biopsy is generally the standard of care, it has several limitations that make it less ideal for pediatric patients and in low resource areas of the world. Therefore, non-endoscopic means for obtaining biopsy samples is of interest in these settings. Areas covered: We review non-endoscopic biopsy techniques reported thus far, and critically examine their merits and demerits regarding their suitability for obtaining biopsy samples in non-sedated subjects. Expert commentary: Esophagogastroduodenoscopy (EGD) is the current standard for acquiring biopsy from the GI tract, however, its limitations include subject sedation, expensive endoscopy infrastructure, expert personnel, and a small but significant risk of complications. A less costly, minimally-invasive and non-endoscopic means for obtaining biopsy samples is therefore of interest for addressing these issues. Such a technology would be of significant impact in low- and middle-income countries where conducting endoscopy is challenging.

Endoscopic biopsy technique in the diagnosis of celiac disease: one bite or two?

BACKGROUND

The diagnosis of celiac disease is dependent on the quality of biopsy specimens obtained at EGD. Endoscopists may obtain a single- or double-biopsy specimen with each pass of the forceps.

OBJECTIVE

To compare the quality of biopsy specimens obtained with the single-biopsy and double-biopsy techniques.

DESIGN

Prospective cohort study.

SETTING

U.S. tertiary-care university hospital.

PATIENTS

Patients undergoing upper endoscopy with confirmed, suspected, or unknown celiac disease status.

INTERVENTIONS

Four biopsy specimens from the second portion of the duodenum: 2 by using the single-biopsy technique (1 bite per pass of the forceps) and an additional 2 by using the double-biopsy technique (2 bites per pass of the forceps). Specimens were blindly reviewed to determine orientation, consecutive crypt-to-villous units, and Marsh score.

MAIN OUTCOME MEASUREMENTS

Proportion of well-oriented biopsy specimens.

RESULTS

Patients (N = 86) were enrolled, 47% with known celiac disease, 36% with suspected celiac disease, and 17% with an unknown celiac disease status. Well-oriented biopsy specimens were noted in 66% of patients with the single-biopsy technique and 42% of patients with the double-biopsy technique (P < .01). Analysis of matched pairs showed improved orientation with the single-biopsy technique (odds ratio 3.1; 95% confidence interval, 1.5-7.1; P < .01). This persisted in subgroup analysis of patients with known celiac disease (P = .02), villous atrophy (P = .02), and a final diagnosis of celiac disease (P < .01).

LIMITATIONS

A single-center trial.

CONCLUSION

The single-biopsy technique improves the yield of well-oriented duodenal biopsy specimens. Endoscopists should consider taking only 1 biopsy specimen per pass of the forceps in patients undergoing biopsies of the duodenal mucosa.

Use of narrow band imaging in assessing duodenal villous atrophy

BACKGROUND AND OBJECTIVE

Narrow band imaging endoscopy with magnification (NBI-ME) has already been established in Barrett's esophagus, stomach, and colonic mucosa, but limited work has been done in the mucosal evaluation of duodenum. A study was done to determine the correlation between NBI and histology in grading villous architecture in varied etiology.

METHOD

A prospective observational study comprising 105 subjects with suspected malabsorption. The presence of a diagnosed celiac disease, severe life threatening comorbidity, or pregnancy was considered as exclusion criteria. Standard endoscopy (SE), NBI-ME, multiple duodenal biopsies with histopathological examination were done in all.

RESULTS

Fifty-one patients had celiac disease while 54 patients comprised mainly functional dyspepsia, iron deficiency anemia, tropical malabsorption syndrome, and irritable bowel syndrome. Four NBI-ME image subtypes of villous morphology have been proposed (NBI type I/II/III/IV). NBI-ME had 95 % sensitivity, 90.2 % specificity, 91.2 % positive predictive value, and 94.2 % negative predictive value for diagnosing altered villous morphology. Intraobserver kappa agreement coefficient (κ) for NBI-ME was 0.83 while interobserver agreement was 0.89 (95 % CI 0.8-0.97).

CONCLUSION

NBI-ME has good performance characteristics and very good kappa intra/interobserver agreement coefficient for varied subtypes of villous morphology. NBI-ME is most useful for obtaining a targeted biopsy which can be missed by conventional white light endoscopy.

Duodenal bulb in celiac adults: the "whether biopsying" dilemma

BACKGROUND

Celiac disease (CD)-related lesions were described in duodenal bulb of celiac patients.

GOAL

Our aim was to evaluate the morphology of bulb mucosa in adult celiac patients and in controls to evaluate its usefulness for CD diagnosis.

STUDY

We studied 43 celiac patients (10 male, median age: 35.2 y) at diagnosis and 43 gastroenterological controls (10 male, median age: 37.8 y), submitted to upper endoscopy for gastroenterological complaints. Histologic lesions were assayed by an experienced pathologist according to the Marsh modified classification. Antiendomysium antibodies and antitransglutaminase antibodies-tTGAb (ELISA and/or RIA) have been tested. In selected patients, DNA was typed for DRB1, DQA1, and DQB1 genes by sequence-specific primer polymerase chain reaction.

RESULTS

In all celiac patients lesions were present in the bulb mucosa. One female with thyroiditis, who had a CD daughter, showed lesions only in the duodenal bulb. Patchy villous atrophy was found in another patient. All celiacs were antiendomysium and/or tTGAb positive. DQ2 heterodimer was present in 5 CD patients. The gastroenterological controls showed normal mucosa in the duodenum.

CONCLUSIONS

This study demonstrates that CD-related histologic lesions are present in duodenal bulb of adult patients. Moreover, the normal aspect of this mucosa in gastroenterological controls implies the high negative predictive value of this finding. Therefore, we suggest taking at least 1 biopsy on the bulb area and 1 from the distal duodenum for CD diagnosis, in all the patients submitted to upper endoscopy, to avoid missed or delayed diagnosis.

European Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines for the diagnosis of coeliac disease

OBJECTIVE

Diagnostic criteria for coeliac disease (CD) from the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) were published in 1990. Since then, the autoantigen in CD, tissue transglutaminase, has been identified; the perception of CD has changed from that of a rather uncommon enteropathy to a common multiorgan disease strongly dependent on the haplotypes human leukocyte antigen (HLA)-DQ2 and HLA-DQ8; and CD-specific antibody tests have improved.

METHODS

A panel of 17 experts defined CD and developed new diagnostic criteria based on the Delphi process. Two groups of patients were defined with different diagnostic approaches to diagnose CD: children with symptoms suggestive of CD (group 1) and asymptomatic children at increased risk for CD (group 2). The 2004 National Institutes of Health/Agency for Healthcare Research and Quality report and a systematic literature search on antibody tests for CD in paediatric patients covering the years 2004 to 2009 was the basis for the evidence-based recommendations on CD-specific antibody testing.

RESULTS

In group 1, the diagnosis of CD is based on symptoms, positive serology, and histology that is consistent with CD. If immunoglobulin A anti-tissue transglutaminase type 2 antibody titers are high (>10 times the upper limit of normal), then the option is to diagnose CD without duodenal biopsies by applying a strict protocol with further laboratory tests. In group 2, the diagnosis of CD is based on positive serology and histology. HLA-DQ2 and HLA-DQ8 testing is valuable because CD is unlikely if both haplotypes are negative.

CONCLUSIONS

The aim of the new guidelines was to achieve a high diagnostic accuracy and to reduce the burden for patients and their families. The performance of these guidelines in clinical practice should be evaluated prospectively.

What is the use of biopsy and antibodies in coeliac disease diagnosis?

The advent of highly sensitive and specific serological markers has led to some protagonists proposing that coeliac disease can be diagnosed without the need for a biopsy. However, this is an area of controversy. Lack of consensus about diagnostic degrees of histological change, paucity of symptoms, antibody-negative disease and immunodeficiency can make diagnosis difficult even with a biopsy. Conversely, an argument can be put forward for a 'no biopsy' approach based on the large number of patients with typical symptoms and positive serology who experience a diagnostic delay. In addition, endoscopy is not without discomfort. This article discusses the use of antibodies and duodenal biopsy within this context. Finally, we propose a pragmatic diagnostic algorithm for clinicians to use when investigating patients for coeliac disease.

Gluten-sensitive enteropathy (celiac disease): controversies in diagnosis and classification

CONTEXT

Celiac disease, or gluten-sensitive enteropathy, is a chronic inflammatory disorder of the small intestine characterized by malabsorption after ingestion of gluten in individuals with a certain genetic background. Clinical presentation can vary from full-blown malabsorption to subtle and atypical symptoms. Diagnosis currently relies on clinicopathologic studies including mucosal biopsy, serologic tests, and the effects of a diet free of gluten on the symptoms. Mucosal pathologic features are also variable, ranging from mild abnormalities, including intraepithelial lymphocytosis, to completely flat mucosa. Since patients with minimal histologic lesion of intraepithelial lymphocytosis often present with normal serologic findings, biopsy diagnosis becomes more important for identifying such individuals. Classification of mucosal pathology in gluten-sensitive enteropathy has been a subject of controversy among pathologists and needs to be revised according to the current understanding of the disease.

OBJECTIVES

To highlight the variations in clinical and pathologic presentation of gluten-sensitive enteropathy, to emphasize the importance of small-intestinal biopsy evaluation in the diagnosis, and to propose a new classification of mucosal pathology in gluten-sensitive enteropathy, in an effort to overcome the problems related to the classification systems currently available.

DATA SOURCES

A review of the literature on clinicopathologic features and the morphologic spectrum of gluten-sensitive enteropathy is presented.

CONCLUSIONS

Considering that there are many entities in the differential diagnosis of gluten-sensitive enteropathy, because of the varied clinicopathologic spectrum of the disease, diagnosis depends on good clinicopathologic communication. The classification that is presented in this review is a simple and practical approach to improve clinicopathologic correlation in gluten-sensitive enteropathy.

The frequency of histologic lesion variability of the duodenal mucosa in children with celiac disease

BACKGROUND

Celiac disease (CD) may cause changes throughout the gastrointestinal tract. Patchy distribution of duodenal mucosal lesions has been described in adults as well as in children. This study aimed to verify the concept and to evaluate the frequency of histologic lesion variability of the duodenal mucosa in Indian children with CD.

METHODS

We enrolled 67 children prospectively who underwent upper gastrointestinal endoscopy because of positive tissue transglutaminase antibodies and biopsy as the final evaluation for suspected CD. Four biopsies were taken from the descending duodenum distal to the papilla, and duodenal bulb. The histologic lesions were classified according to the Oberhuber classification with modification proposed by our group.

RESULTS

Forty-three CD children (64.2%) had a "mixed" type 3 lesion characterized by a different degree of villous atrophy at different biopsy sites. Eight children (11.9%) showed two different types of histologic lesions in the same patient at different biopsy sites. The overall variability of histologic lesion (variability in the grade of villous atrophy [type 3a, 3b, or 3c], and coexistence of villous atrophy and type 2 lesion) was seen in 51 (76.1%) of the CD patients.

CONCLUSIONS

Children with CD show a high frequency of variability of histologic lesions. Therefore, multiple endoscopic biopsy specimens should be obtained not only from the distal duodenum but also from the bulb.

Variability of histopathological changes in childhood celiac disease

OBJECTIVES

Adult studies of celiac disease (CD) have shown that duodenal mucosal histopathological changes may be patchy, and the diagnostic utility of duodenal bulb biopsies is believed to be limited. Few related pediatric data exist.

METHODS

We assessed the prevalence of variable biopsy findings and duodenal bulb involvement in children with CD, as well as its association with clinical parameters. A total of 198 consecutive cases of CD diagnosed at the Children's Hospital during 2001-2005 were analyzed. All biopsies were scored by a pathologist blinded to the clinical data using the Marsh criteria. Mucosal changes were classified as focal if changes consistent with CD and normal mucosa were found within a single biopsy fragment. Patchiness was defined as variation of at least one Marsh grade between separate fragments in a biopsy set.

RESULTS

The median age was 9.3 years; 62% were female. An average of 3.6 biopsy samples was obtained per case. In 101 cases, biopsy samples were obtained from the duodenal bulb and the second portion of the duodenum. Focality was present in biopsy samples collected from 36 (18%) cases. Patchiness was found in 105 (53%) cases, and at least 1 normal biopsy fragment was present in 71 (36%) cases. In 10 cases, only the bulb biopsies were diagnostic of CD. There was no association with the clinical features examined.

CONCLUSIONS

Duodenal involvement in pediatric CD is frequently patchy and may show variable severity even within a single biopsy fragment. Variability cannot be predicted by clinical characteristics. Multiple endoscopic biopsies, including the duodenal bulb, should be obtained in suspected pediatric CD cases to maximize diagnostic yield.

Optical coherence tomography in pediatric patients: a feasible technique for diagnosing celiac disease in children with villous atrophy

BACKGROUND AND AIM

Celiac disease is a common condition with many atypical manifestations, where histology serves as the "gold standard" for diagnosis. A useful new technique, optical coherence tomography, can depict villous morphology in detail, using light waves. This study examined the correlation between the sensitivity and specificity of optical coherence tomography in pediatric patients undergoing esophago-gastro-duodenoscopy for the diagnosis of celiac disease.

MATERIALS AND METHODS

A total of 134 children were prospectively enrolled, 67 with a serological suspicion of celiac disease (group 1) and 67 with negative histology for celiac disease (group 2). During a diagnostic esophago-gastro-duodenoscopy we acquired multiple images and films in the four quadrants of the second part of the duodenum, and biopsies were taken in the area where optical coherence tomography had been done. Three patterns of villous morphology were considered: pattern 1=no atrophy (types 0, 1 or 2 of the Marsh classification); pattern 2=mild atrophy (type 3a or 3b); pattern 3=marked atrophy (type 3c).

RESULTS

The diagnosis of celiac disease was histologically confirmed in all 67 children with positive antiendomysium and/or antitransglutaminase antibodies. Optical coherence tomography correlated with pattern 1 histology in 11/11 cases, pattern 2 in 30/32 (93.8%) and pattern 3 in 22/24 (91.6%). Sensitivity and specificity were 82% and 100%. In the control group there was 100% concordance between optical coherence tomography and histology. The overall concordance between optical coherence tomography and histology in determining patchy lesions was 75%.

CONCLUSION

Optical coherence tomography could be a helpful diagnostic tool in children with mild or marked villous atrophy for diagnosing celiac disease during upper gastrointestinal (GI) endoscopy, avoiding biopsies. However, duodenal biopsies are mandatory if the optical coherence tomography shows normal villous morphology in patients with positive antibodies.

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.

Assessment of the diagnostic value of duodenal bulb histology in patients with celiac disease, using multiple biopsy sites

BACKGROUND

Multiple endoscopic biopsies from the descending duodenum are usually recognized as the standardized method for the evaluation of mucosal changes in celiac disease (CD). Generally, the duodenal bulb is not considered a useful site for biopsies, owing to some difficulties in histologic evaluation.

GOAL

We wanted to verify if duodenal bulb histology establish a correct diagnosis of CD.

STUDY

Fifty-two consecutive children with suspicion of CD and positive antitissue transglutaminase antibodies were enrolled in a prospective fashion. During upper gastrointestinal endoscopy, 2 to 4 biopsies each were taken from descending duodenum distal to the papilla of Vater (D2) and duodenal bulb (B). The histologic lesions were classified according to the modified Oberhuber classification by single pathologist who was blinded to the site of biopsy.

RESULTS

A total of 52 children had a final diagnosis of CD. The main presenting symptoms were diarrhea 43/52 (82.7%), anemia 40/52 (76.9%), and failure to thrive 32/52 (61.5%). All had type 3 lesion-(a) mild, (b) moderate, or (c) severe-in at least 1 site. There was 45/52 (86.5%) CD patients with lesions of identical type (type 2 or 3) in both biopsy sites. The number of intraepithelial lymphocytes was not significantly different in the descending part of the duodenum as compared with duodenal bulb.

CONCLUSIONS

The biopsies from the duodenal bulb and second part of the duodenum in CD can be equally representative of the underlying disease. The diagnosis of CD can reliably be made even if biopsies are taken from the duodenal bulb rather than distal duodenum or jejunum.

Pearls and pitfalls in the diagnosis of adult celiac disease

In adults with diarrhea or suspected malabsorption, a diagnosis of celiac disease requires that two criteria be fulfilled: first, a demonstration of typical pathological changes of untreated disease in biopsies from the proximal small bowel; and second, evidence should exist that clinical (and/or pathological) changes are gluten-dependent, most often as an unequivocal response to a gluten-free diet. Pathological abnormalities of celiac disease may include severe ('flat') or variably severe (mild or moderate) small bowel mucosal architectural abnormalities that are associated with both epithelial cell and lymphoid cell changes, including intraepithelial lymphocytosis. Architectural changes tend to be most severe in the duodenum and proximal jejunum and less severe, or absent, in the ileum. These findings, while characteristic of celiac disease, are not specific because several other conditions can produce similar changes. Some serological assays (eg, tissue transglutaminase antibody assays) are very useful screening tools in clinical practice because of their high specificity and sensitivity, but these do not provide a definitive diagnosis. The most critical step in the diagnosis of celiac disease is the demonstration of its gluten-dependent nature. The clinical response to gluten restriction in celiac disease is usually reflected in the resolution of diarrhea and weight gain. Normalization of biopsy changes can be first shown in the most distal intestinal sites of involvement, and later, sometimes only after prolonged periods (months to years) in the duodenum. Rarely, recurrent (or refractory) celiac disease may occur after an initial gluten-free diet response. Finally, some with 'sprue-like intestinal disease' cannot be classified because a diet response fails to occur. This may be a heterogeneous group, although some are eventually found to have a malignant lymphoma.

Classification of villous atrophy with enhanced magnification endoscopy in patients with celiac disease and tropical sprue

BACKGROUND

Intestinal lesions in celiac disease (CD) and tropical sprue (TS) can be patchy. Improved endoscopic identification of affected areas may increase the diagnostic yield of biopsy specimens. Enhanced magnification endoscopy [EME] combines magnification endoscopy with 3% acetic acid instillation.

OBJECTIVE

This study describes endoscopic findings associated with villous atrophy during EME.

DESIGN

Patients underwent EME with a magnifying endoscope with acetic-acid application. Surface mucosal patterns were characterized before and after acetic-acid spraying. Observed surface patterns were compared with histologic results obtained from a single targeted biopsy specimen.

SETTING

Policlinica Metropolitana in Caracas, Venezuela.

PATIENTS

Patients with diagnosed but untreated CD or TS.

RESULTS

Fifty-two biopsy specimens were obtained from 27 patients (17 men, 10 women; mean age 50.5 years; range, 24-76 years; 12 with CD and 15 with TS). EME of the duodenum revealed 4 different mucosal patterns: I, normal; II, stubbed; III, ridged; and IV, foveolar. Three of the 4 patterns were strongly associated with the presence of villous atrophy (pattern I, 1/18 [5.5%]; II, 16/17 [94%]; III, 12/12 [100%]; and IV, 5/5 [100%]). EME was more sensitive than standard endoscopy for detecting villous atrophy, 100% versus 58% in CD and 93% versus 20% in TS. Furthermore, EME identified patchy areas of partial villous atrophy in 16 patients (5 CD and 11 TS) in whom standard endoscopy was normal.

CONCLUSIONS

EME identifies 3 characteristic endoscopic patterns that correlate with the presence of villous atrophy. EME could help identify patchy areas of partial mucosal atrophy, potentially reducing the need for blind biopsies.

An approach to duodenal biopsies

The introduction of endoscopy of the upper digestive tract as a routine diagnostic procedure has increased the number of duodenal biopsy specimens. Consequently, the pathologist is often asked to evaluate them. In this review, a practical approach to the evaluation of a duodenal biopsy specimen is discussed. An overview of the handling of specimens is given and the normal histology and commonly encountered diseases are discussed. Finally, a description of commonly seen infections is provided, together with an algorithmic approach for diagnosis.

Endoscopy in celiac disease

PURPOSE OF REVIEW

The primary objective of this review is to highlight the evidence for the role of endoscopy in celiac disease.

RECENT FINDINGS

Evidence is presented that the endoscopic markers of celiac disease are specific although not sensitive for the disease. Villous atrophy, the hallmark of celiac disease, is patchy in the duodenum, and various techniques may identify areas of villous atrophy. These methods include magnification endoscopy and chromoendoscopy. The most recent innovation, video capsule endoscopy, may be of value in the diagnosis of celiac disease and in the assessment of patients with complicated celiac disease.

SUMMARY

Endoscopy and duodenal biopsies are the mainstay for diagnosing celiac disease. Although characteristic endoscopic features may be useful, their absence does not exclude celiac disease. Random biopsy, even of normal-appearing mucosa is necessary for the diagnosis of celiac disease.

Pathological and clinical significance of increased intraepithelial lymphocytes (IELs) in small bowel mucosa

Intestinal intraepithelial lymphocytes (IELs) belong to a unique T-cell population interspersed between epithelial cells of both the small and large intestine. It is becoming increasingly recognised that an increased number of IELs with a normal villous architecture is within the wide spectrum of histological abnormalities observed in coeliac disease. An increased number of IELs is the earliest pathological change following gluten challenge and a high IEL count may be the only sign of gluten sensitivity. Therefore, the finding of a raised IEL count with normal villous architecture is of sufficient clinical importance to be reported in routine small bowel biopsies. However, it is evident that not all small intestinal biopsy specimens showing increased IELs are explained by gluten sensitivity. Increased IELs in small bowel mucosa have also been associated with autoimmune disorders, tropical sprue, food protein intolerance, Helicobacter pylori-associated gastritis, peptic duodenitis, parasitic and viral infections, as well as the development of intestinal lymphoma. Histological examination of a biopsy specimen of the small bowel remains the diagnostic gold standard for coeliac disease. There will be an ever increasing demand for histological confirmation of gluten sensitivity in patients in whom the classic microscopic appearance of flattened villi may not have fully developed. The more widespread recognition by histopathologists of the pattern of injury manifested by increased numbers of IELs in intestinal biopsy specimens will certainly help in early diagnosis of coeliac disease, lessen diagnostic confusion and influence the modern practice of gastrointestinal tract medicine. This review discusses some of the recent developments in clinical pathology pertaining to increased IELs in small bowel mucosal biopsies.

Marcadores serológicos y genéticos en el diagnóstico y seguimiento de la enfermedad celíaca

INTRODUCTION

Understanding of celiac disease has changed with the advent of serological markers (antigliadin IgA, anti-endomysial IgA and anti-transglutaminase IgA antibodies) and with the identification of major susceptibility genes (HLA-DQA1*05-DQB1*02). Reports of the efficacy of these diagnostic tests have varied, depending on the methodology used and the population investigated.

OBJECTIVES

To determine the clinical utility of genetic and serological markers in the diagnosis of celiac disease, their relationship with histological lesions and their changes during treatment, in order to establish an optimal diagnostic algorithm in our environment.

PATIENTS AND METHODS

We performed a retrospective study of 590 patients from the health area of Badajoz referred to the Immunology Laboratory for screening or follow-up of celiac disease. The results of intestinal histology, serological markers (antigliadin IgA, anti-endomysial IgA and anti-transglutaminase IgA antibodies), and genomic typing (HLA-DQA1*05-DQB1*02) were analyzed.

RESULTS

The sensitivity and specificity of serological tests were greater than 90 %, with a negative predictive value of 98-100 %. HLA-DQA1*05-DQB1*02 was detected in 97 % of celiac patients, with a very high negative predictive value (99 %). On biopsy, 95 % of the patients with some grade of intestinal lesion were positive for antigliadin and/or anti-endomysial antibodies.

CONCLUSION

To avoid missed diagnoses, the diagnostic algorithm of celiac disease should include at least two serological markers (antigliadin antibodies and anti-endomysial and/or anti-transglutaminase antibodies) and IgA quantification. Genomic typing should be carried out if one or more markers are positive or if the subject belongs to any of the risk groups. The physician should decide on the advisability of intestinal biopsy on the basis of the patient's clinical and immunological history.

Variability of histologic lesions in relation to biopsy site in gluten-sensitive enteropathy

OBJECTIVES

It is generally believed that in gluten-sensitive enteropathy or celiac disease (CD), mucosal lesions may have a patchy distribution. We wanted to verify this concept and establish whether one or more biopsy samples are needed in order to make a correct diagnosis of CD.

METHODS

One hundred and twelve consecutive children with positive antiendomysium (EMA) or antitissue transglutaminase (tTGA) antibodies, referred to us for suspected CD, were enrolled in a prospective fashion. During upper GI endoscopy four to five biopsies were taken from Treitz and/or distal duodenum (D3), intermediate duodenum (D2), proximal duodenum (D1), and duodenal bulb (B). Histologic lesions were classified according to Marsh criteria modified by Oberhuber.

RESULTS

A total of 110 patients, all HLA-DQ2 or DQ8 positive, had a final diagnosis of CD (59 classic, 28 atypical, and 23 silent): 102/110 (92.7%) had type 3 lesion-(a) mild, (b) moderate, or (c) severe-in at least one site and 94/110 (85.4%) had villous atrophy (VA) of some degree in all sites. VA of identical degree was present in all biopsy sites in 55/110 (50%) patients. Total VA (type 3c) was present in at least one site in 85/110 (75%), in all sites in 50/110 (45.4%), and significantly increased in aborad direction ((chi(2) > 26.22 with (= 0.01 and d.f. (degrees of freedom) = 12). Eight out of 110 (7.2%) CD patients had exclusively type 1 or 2 lesions, no patient had lesion variability >1 degree and none had normal biopsies. There was no correlation between type or distribution of histologic lesions and clinical presentation of CD.

CONCLUSIONS

Mucosal atrophy is present in 85% of patients with CD and total VA is significantly more frequent in distal duodenum or proximal jejunum. Fifty percent of patients have identical VA throughout the duodenum and no duodenal areas are histologically normal. In genetically susceptible children with positive serology, a diagnosis of CD can reliably be made even if biopsies are not taken from the distal duodenum or jejunum.

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Patchy villous atrophy of the duodenum in childhood celiac disease

OBJECTIVES

Patchy villous atrophy of the duodenal mucosa has been described in adults with untreated celiac disease (CD) but not in children. The authors evaluated the presence and the distribution of villous atrophy in children with celiac disease to see whether this histologic pattern exists in children.

METHODS

We studied 95 children at diagnosis (Group 1) and seven during gluten challenge (Group 2). We measured anti-endomysium antibodies (EMA) by immunofluorescence on monkey esophagus, antihuman-tissue transglutaminase autoantibodies (anti-tTG Abs) by radioimmunoprecipitation, and HLA-DQ2/DQ8 heterodimers by polymerase chain reaction using specific primers. During upper intestinal endoscopy, at least five duodenal biopsy samples were obtained, one from the duodenal bulb and four from the distal duodenum.

RESULTS

Thirteen of 95 (13.7%) patients in Group 1 and in 3 of 7 (42.9%) in Group 2 had patchy villous atrophy of the duodenum. In all 16 patients, villous atrophy of the bulb was present. In four children from Group 1, villous atrophy was observed only in the bulb samples. EMA, anti-tTG Abs, and HLA-DQ2/DQ8 heterodimers were present in all patients. Fourteen of 16 had symptomatic CD, and two were silent, detected during screening in subjects at risk for CD.

CONCLUSIONS

This is the first study demonstrating that children with CD may have patchy villous atrophy of the duodenum. The bulb mucosa may be the only duodenal area involved, both at diagnosis and after gluten challenge. Therefore, multiple endoscopic biopsies should always be performed, not only in the distal duodenum, but also in the bulb.

Endoscopic markers in adult coeliac disease

BACKGROUND

Various endoscopic markers have been described in coeliac disease, particularly in the second part of the duodenum, with minor attention generally being paid to the duodenal bulb.

AIMS

To evaluate, prospectively, the presence of all endoscopic markers in the bulb and the second part of the duodenum on a large series of patients submitted to endoscopy for duodenal biopsy. PATIENTS AND METHODS. A total of 367 consecutive patients, submitted to endoscopy with duodenal biopsy for various indications, were considered. Biopsies were graded as normal, with partial villous atrophy (mild, moderate, severe) or with subtotal villous atrophy. Endoscopic markers and corresponding locations evaluated were: micronodular pattern [bulb and descending duodenum], mosaic appearance (bulb and descending duodenum), scalloped folds (descending duodenum), reduced or absent folds (descending duodenum).

RESULTS

In 78 patients, a diagnosis of untreated coeliac disease was made. Endoscopic markers were seen in 73/78 patients, with only a single sign present (bulb or descending duodenum) in 12 patients. In the remaining 289 patients, normal histology and normal endoscopic findings were observed, except in two patients with reduced folds. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy regarding all endoscopic markers were 93.6%, 99.3%, 97.3%, 98.3% and 98.1%, respectively

CONCLUSIONS

This study confirms the usefulness of endoscopic markers in detecting coeliac disease, underlining the importance of evaluating also abnormalities in the bulb and endoscopic single signs; although endoscopy may not detect all cases of coeliac disease, the recognition of endoscopic markers allows the selection for biopsy of unsuspected patients submitted to endoscopy for non-specific symptoms.

Diagnosis of celiac sprue

Celiac sprue is a common lifelong disorder affecting 0.3-1% of the Western world and causing considerable ill health and increased mortality, particularly from lymphoma and other malignancies. Although high prevalence rates have been reported in Western Europe, celiac sprue remains a rare diagnosis in North America. Whether celiac sprue is truly rare among North Americans or is simply underdiagnosed is unclear, although serological screening of healthy American blood donors suggests that a large number of American celiacs go undiagnosed. Celiac sprue is an elusive diagnosis, and often its only clue is the presence of iron or folate deficiency anemia or extraintestinal manifestations, such as osteoporosis, infertility, and neurological disturbances. The challenge for gastroenterologists and other physicians is to identify the large population of undiagnosed patients that probably exists in the community and offer them treatment with a gluten-free diet that will restore the great majority to full health and prevent the development of complications. The advent of highly sensitive and specific antiendomysium and tissue transglutaminase serological tests has modified our current approach to diagnosis and made fecal fat and D-xylose absorption testing obsolete. A single small bowel biopsy that demonstrates histological findings compatible with celiac sprue followed by a favorable clinical and serological response to gluten-free diet is now considered sufficient to definitely confirm the diagnosis. We review the wide spectrum of celiac sprue, its variable clinical manifestations, and the current approach to diagnosis.

Histologic evaluation of endoscopic versus suction biopsies of small intestinal mucosae in children with and without celiac disease

BACKGROUND

Concern over the adequacy of histologic diagnosis of endoscopic duodenal biopsies in children prompted this comparative study on the histologic quality of endoscopic versus capsule biopsies. We found this problem addressed in only six previous reports.

METHODS

Blind examinations of the histologic sections of 48 duodenal biopsies obtained by gastrointestinal endoscopy in children aged 2-18 years were compared to 52 biopsies obtained by the small bowel suction method (from children aged 1-16 years).

RESULTS

Although 87.5% of endoscopic biopsies and 94.2% of capsule biopsies were adequate for histologic diagnosis, fragmentation or squashing was seen in 83.3% of endoscopic biopsies and only in 25% of capsule biopsies.

CONCLUSIONS

Biopsies obtained by suction are of better quality than those obtained by endoscopy. If endoscopy is preferred for technical reasons, the following conditions should be observed: the patients should be aged over 2 years, and a minimum of four biopsies should be obtained with forceps of a diameter greater than 2 mm. Adequate histologic criteria for diagnosis should include at least one full-thickness mucosal specimen more than 3 mm in length, vertically oriented, and not fragmented. In children under age 2, duodenal or jejunal capsule biopsies are preferred, since the specimens are usually larger and less fragmented. Endoscopy is technically more difficult in the very young patient.

Usefulness of videoduodenoscopy and vital dye staining as indicators of mucosal atrophy of celiac disease: assessment of interobserver agreement

BACKGROUND

The present study was designed to determine the diagnostic usefulness of videoduodenoscopic inspection alone and the addition of vital dye staining in the detection of celiac disease. We additionally sought to evaluate interobserver agreement for specific duodenoscopic markers of mucosal atrophy.

METHODS

One hundred sixty-seven consecutive subjects who underwent duodenoscopy for intestinal biopsy were included in a prospective controlled study. Endoscopic examination was performed by experienced endoscopists according to a set protocol using methylene blue (1%) dye. All procedures were recorded on videotape, but only 20 (10 with atrophy and 10 normal) were used in a blinded, independent, randomized analysis by five reviewers to evaluate interobserver agreement. Endoscopic signs indicative of mucosal atrophy were as follows: reduction in the number or loss of Kerkring's folds, "scalloped" folds, "mosaic pattern," and visualization of the underlying blood vessels.

RESULTS

Eighty-seven patients had celiac disease (57 newly diagnosed, 30 when treated). Seven treated patients had nonatrophic mucosa. In 80 patients the final diagnosis excluded celiac disease. Videoendoscopic inspection alone correctly identified 75 of 80 patients with complete mucosal atrophy and 86 of 87 with normal mucosa. False-negative diagnoses occurred in treated celiac patients with mild atrophy. Mosaic pattern (89%) and scalloped folds (86%) were the most useful endoscopic signs. Vital dye staining, as assessed by experienced endoscopists, provided identical results to those obtained by inspection alone. Sensitivity, specificity, and positive and negative predictive values for the presence of one or more than one feature were 94%, 100%, 100%, and 96%, respectively. The agreement (kappa statistics) among observers was excellent for the mosaic pattern (kappa: 0.76 for both the videoendoscopic inspection alone and dye staining) and the scalloped folds (kappa: 0.83 and 0.76, respectively) and was fair (kappa: 0.41 and 0.59, respectively) for the reduction in the number or loss of duodenal folds.

CONCLUSION

This study confirms that videoduodenoscopy is useful in the detection of intestinal atrophy. Dye staining produces a better delineation of scalloped folds and mosaic pattern in the atrophic mucosa, but did not provide additional information to the expert endoscopist. Finally, interobserver agreement was excellent for the most prevalent signs.

Paediatric upper gastro-intestinal endoscopy in developing countries

A retrospective study of 200 endoscopies performed on 168 children (90 girls and 78 boys) aged 3 months to 18 years (median 6 years) is reported. All procedures were completed successfully in an adult endoscopy unit in a comprehensive health centre. Most children of less than 6 months and above 12 years of age needed no intravenous sedation. One child developed respiratory depression and was successfully resuscitated. Indications for endoscopy were: small intestinal biopsy, 78 (46%); recurrent abdominal pain, 40 (24%); acute epigastric pain, 13 (8%); persistent vomiting, 12 (7%); haemorrhage, 10 (6%); caustic substance ingestion, six (4%); and dysphagia, four (2%) children. Positive diagnoses were obtained in 123 (62%) procedures. Coeliac disease (26 cases) was the most common histological diagnosis, followed by gastritis (19 cases), oesophagitis (18 cases), duodenitis (16 cases), duodenal ulcer (11 cases), hiatus hernia (six cases), gastric ulcer (three cases) and oesophageal stricture (two cases). Where specialized paediatric endoscopy units are not feasible, e.g. in developing countries, endoscopic services for children can be safely provided by paediatric endoscopists as part of an adult endoscopy service, provided that suitable resuscitation equipment is available and the necessary modifications to meet the medical and psychological needs of children and their parents are taken into consideration.

Small bowel biopsy by remote control: experimental study on dogs

Telemetry has been used for 30 years in medicine because it requires no link between patients and apparatus. To take advantage of this, we have developed a multipurpose intestinal capsule for the small bowel, with interchangeable tips triggered by remote control. A new tip, performing small bowel mucosal biopsy by remote control is presented. The location of the capsule is radiotransmitted by means of a cogwheel, which is rotated by contact with the intestinal wall. At the chosen site (ie, a number of centimeters from the pylorus), the remote control is activated and the mucosal biopsy is performed through a suction port and kept inside the tip. The capsule then passes throughout the bowel and is recovered in the stool to allow examination of the biopsies. The results of 24 studies on a dog (crossing of the pylorus, length, transit time, velocity) are analyzed to validate the method. Biopsies were accomplished in the stomach, the small bowel (ileum), and the colon. The device failed two times, but no complications occurred. Biopsies, with average surfaces were 6mm2, never penetrated the longitudinal muscular layer. The system is precise to within 3 cm, efficient, reliable, noninvasive, and causes minimal discomfort during investigation.

Effect of forceps size and mode of orientation on endoscopic small bowel biopsy evaluation

Endoscopy is increasingly being used to obtain duodenal biopsy specimens in suspected small intestinal malabsorption. We have prospectively evaluated the effect of standard and jumbo biopsy forceps, as well as the mode of orientation of the specimens (naked eye or stereomicroscopy), on duodenal biopsy weight, length, depth, and orientation in 18 consecutive patients. A pair of biopsy specimens was obtained from each patient by each type of forceps in random order. After they had been weighed, one biopsy specimen from each pair was oriented stereomicroscopically and all four were blindly evaluated by two pathologists. The biopsy specimens obtained with the jumbo forceps were significantly larger (15.9 +/- 6.9 mg, mean +/- SD) and longer (0.6 +/- 0.2 cm) than those obtained with the standard forceps (8.0 +/- 1.3 mg, 0.4 +/- 0.2 cm, respectively; p < 0.001). Seventy-two percent of the jumbo biopsy specimens that were oriented with stereomicroscopy included a minimum of four villi in a row, as compared to 44% of the eye-oriented jumbo specimens and less than 39% of the standard specimens, irrespective of the mode of orientation (p = 0.02). These results indicate that the jumbo forceps is superior to the standard, because it produces a larger duodenal mucosal specimen, usually suitable for optimal histologic evaluation when oriented with stereomicroscopy.

Structural changes of duodenum brush border in lung cancer patients treated with cisplatin plus etoposide

The effects of cisplatin plus etoposide chemotherapy (PE) on the structure of proximal intestine villi and brush border were investigated in 10 patients with lung cancer. The day before starting chemotherapy (time 1); 8 days after its initiation (time 2), and one month after the 3rd course of PE (time 3) they underwent esophagogastroduodenoscopy and three biopsies were taken from the descending duodenum. Intestinal villi were examined by light microscopy; brush border by transmission electron microscopy. No significant histological changes of villous pattern were observed at times 2 and 3. The height of microvilli was reduced in seven patients at time 2 (P < 0.05). Microvilli abnormalities (i.e. rarefaction and/or heterogeneity in their height) were present in nine patients at time 2 (P < 0.05). Brush border appearance at time 3 did not differ from that at time 1. PE chemotherapy seems to have short-term toxic effects on small intestine brush border, but does not cause chronic enteropathy.

Comparison of endoscopic forceps biopsies and capsule biopsies in determining disaccharidase activity in the duodenum

Endoscopic biopsy is an accepted technique for obtaining samples of small bowel mucosa for histological examination. In this study a comparison between endoscopic forceps biopsies and capsule biopsies in estimating disaccharidase enzyme activity in the small bowel was evaluated. Disaccharidase levels on 168 consecutive small bowel biopsies obtained by either endoscopic biopsy or capsule biopsy were reviewed retrospectively. There was no significant difference in enzyme activity in samples collected by either method. Another 18 patients had simultaneous endoscopic and capsule biopsies from the second part of the duodenum. Again, there was no difference in enzyme activity between samples collected by either technique at the same level in the duodenum. The disaccharidase activity in forceps biopsies taken from the second part of the duodenum is equivalent to those obtained by capsule biopsy.

Endoscopic small bowel mucosal biopsy: a controlled trial evaluating forceps size and biopsy location in the diagnosis of normal and abnormal mucosal architecture

This study was designed to determine (1) whether the site of biopsy within the proximal small bowel affects the ability to assess mucosal architecture in general, or to confirm a diagnosis of celiac sprue specifically; and (2) whether endoscopic small bowel biopsy using standard forceps can obtain adequate biopsy specimens to detect or exclude mucosal abnormalities. Three-hundred fifty-two biopsy specimens were obtained prospectively from 26 patients (8 sprue, 2 nonspecific changes, 16 normal) with "jumbo" and standard forceps from jejunum, ligament of Treitz, fourth, third, and second portions of the duodenum. There was no difference in biopsy specimen quality from different locations. All celiac sprue patients had at least one good or excellent specimen from each location, thereby allowing the diagnosis to be made equally well from second, third, and fourth portions of the duodenum, as well as at the ligament of Treitz and jejunum. No false-positive diagnoses of celiac sprue were made. Finally, the standard biopsy forceps provided good or excellent specimens in all patients.