Serology-based criteria for adult coeliac disease have excellent accuracy across the range of pre-test probabilities

Opportunities for Improving Biopsy and Non-Biopsy-Based Diagnosis of Celiac Disease

The accumulating data regarding a non-biopsy diagnosis of celiac disease has led to its adoption in certain scenarios, although debate on whether and when to use non-biopsy criteria in clinical practice is ongoing. Despite the growing popularity and evidence basis for a biopsy-free approach to diagnosis in the context of highly elevated serologies, there will continue to be a role for a biopsy in some groups. This review summarizes the current evidence supporting a non-biopsy approach and arguments supporting continued reliance on biopsy, and focuses on opportunities to improve both approaches.

Intraepithelial Lymphogram in the Diagnosis of Celiac Disease in Adult Patients: A Validation Cohort

BACKGROUND

Celiac disease is a gluten-related pathology, highly prevalent and heterogeneous in its clinical presentation, which leads to delays in diagnosis and misdiagnosis. The analysis of duodenal intraepithelial lymphocytes (IELs) by flow cytometry (lymphogram) is emerging as a discriminative tool in the diagnosis of various forms of celiac disease (CD).

AIMS

The aim of this study was to validate IEL lymphogram performance in the largest adult series to our knowledge, in support of its use as a diagnostic tool and as a biomarker of the dynamic celiac process.

METHODS

This was a retrospective study including 768 adult patients (217 with active CD, 195 on a gluten-free diet, 15 potential CD patients, and 411 non-celiac controls). The IEL subset cut-off values were established to calculate the diagnostic accuracy of the lymphogram.

RESULTS

A complete celiac lymphogram profile (≥14% increase in T cell receptor [TCR]γδ IELs and simultaneous ≤4% decrease in surface-negative CD3 [sCD3-] IELs) was strongly associated with active and potential forms in over 80% of the confirmed patients with CD, whereas the remaining patients with CD had partial lymphogram profiles (≥14% increase in TCRγδ or ≤4% decrease in sCD3- IELs), with lower diagnostic certainty. None of these patients had a non-celiac lymphogram. Quantifying the TCRγδ versus sCD3- imbalance as a ratio (≥5) is a discriminative index to discard or suspect CD at diagnosis.

CONCLUSIONS

We have validated the IEL lymphogram's diagnostic efficiency (79% sensitivity, 98% specificity), with an LR+ accuracy of 36.2. As expected, the increase in TCRγδ IELs is a reliable marker for celiac enteropathy, while changes in sCD3- IEL levels throughout the dynamic CD process are useful biomarkers of mucosal lesions.

Coeliac disease: the paradox of diagnosing a food hypersensitivity disorder with autoantibodies

Serum antibodies to the autoantigen transglutaminase 2 (TG2) are increasingly harnessed to diagnose coeliac disease. Diagnostic guidelines for children give recommendation for a no-biopsy-based diagnosis through detection of high amounts of IgA anti-TG2 antibodies in serum with confirmation of positivity in a separate blood sample by characteristic autoantibody-staining of tissue. While measurement of IgA anti-TG2 also is important in the diagnostic workup of adults, the adult guidelines still mandate examination of gut biopsies. This requirement might well change in the future, as might the necessity for confirming autoantibody positivity by tissue staining. The key role of autoantibody serology for diagnosis of coeliac disease is paradoxical. Coeliac disease was considered, and still can be considered, a food intolerance disorder where autoantibodies at face value are out of place. The immunological mechanisms underlying the formation of autoantibodies in response to gluten exposure have been dissected. This review presents the current insights demonstrating that the autoantibodies in coeliac disease are intimately integrated in the maladapted immune response to gluten.

Measured levels of positive transglutaminase 2 antibodies are not associated with presentation or incidental endoscopic findings at celiac disease diagnosis

OBJECTIVES

It has been suggested that celiac disease could be diagnosed non-invasively in adults with transglutaminase antibody (TGA) levels >10x upper limit of normal (ULN). It is, however, unclear if high values signify more advanced disease and higher risk of co-morbidities. We investigated the association between the TGA levels, clinical characteristics and non-celiac endoscopic findings.

METHODS

Medical data on 450 celiac disease patients at diagnosis were collected. They were further divided into those with high positive (>10x ULN, n = 164), moderately positive (1-10x ULN, n = 219), and negative (n = 67) TGA.

RESULTS

Median age of patients was 50 years and 60% were women. Patients with negative TGA were older (median age 58 vs. 51 vs. 46 years respectively, p = 0.002) and had more often weight loss (27% vs. 10% vs. 9%, p < 0.001) and abdominal pain or dyspepsia (40% vs 27% vs. 22%, p = 0.017) than did those with moderately positive/high TGA. The groups did not differ in sex, BMI, or other symptoms. Major endoscopic findings included one esophageal adenocarcinoma presenting with dysphagia, six esophagitis, three gastric ulcers, and 39 H. Pylori or other active gastritis. High, moderately positive or negative TGA levels were not associated with these findings in crude or age-adjusted analyses.

CONCLUSIONS

Presentation was similar in patients with moderate or high levels of TGA, whereas patients with negative TGA were different. The level of TGA was not associated with incidental endoscopic findings and the only malignancy presented with an alarm symptom atypical to celiac disease.

Accuracy of the No-Biopsy Approach for the Diagnosis of Celiac Disease in Adults: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Current international guidelines recommend duodenal biopsies to confirm the diagnosis of celiac disease in adult patients. However, growing evidence suggests that immunoglobulin A (IgA) anti-tissue transglutaminase (tTg) antibody levels ≥10 times the upper limit of normal (ULN) can accurately predict celiac disease, eliminating the need for biopsy. We performed a systematic review and meta-analysis to evaluate the accuracy of the no-biopsy approach to confirm the diagnosis of celiac disease in adults.

METHODS

We systematically searched MEDLINE, EMBASE, Cochrane Library, and Web of Science from January 1998 to October 2023 for studies reporting the sensitivity and specificity of IgA-tTG ≥10×ULN against duodenal biopsies (Marsh grade ≥2) in adults with suspected celiac disease. We used a bivariate random effects model to calculate the summary estimates of sensitivity, specificity, and positive and negative likelihood ratios. The positive and negative likelihood ratios were used to calculate the positive predictive value of the no-biopsy approach across different pretest probabilities of celiac disease. The methodological quality of the included studies was evaluated using the QUADAS-2 tool. This study was registered with PROSPERO, number CRD42023398812.

RESULTS

A total of 18 studies comprising 12,103 participants from 15 countries were included. The pooled prevalence of biopsy-proven celiac disease in the included studies was 62% (95% confidence interval [CI], 40%-83%). The proportion of patients with IgA-tTG ≥10×ULN was 32% (95% CI, 24%-40%). The summary sensitivity of IgA-tTG ≥10×ULN was 51% (95% CI, 42%-60%), and the summary specificity was 100% (95% CI, 98%-100%). The area under the summary receiver operating characteristic curve was 0.83 (95% CI, 0.77 - 0.89). The positive predictive value of the no-biopsy approach to identify patients with celiac disease was 65%, 88%, 95%, and 99% if celiac disease prevalence was 1%, 4%, 10%, and 40%, respectively. Between-study heterogeneity was moderate (I2 =30.3%), and additional sensitivity analyses did not significantly alter our findings. Only 1 study had a low risk of bias across all domains.

CONCLUSION

The results of this meta-analysis suggest that selected adult patients with IgA-tTG ≥10×ULN and a moderate to high pretest probability of celiac disease could be diagnosed without undergoing invasive endoscopy and duodenal biopsy.

Identifying the Optimum Strategy for Identifying Adults and Children With Celiac Disease: A Cost-Effectiveness and Value of Information Analysis

OBJECTIVES

Celiac disease (CD) is thought to affect around 1% of people in the United Kingdom, but only approximately 30% are diagnosed. The aim of this work was to assess the cost-effectiveness of strategies for identifying adults and children with CD in terms of who to test and which tests to use.

METHODS

A decision tree and Markov model were used to describe testing strategies and model long-term consequences of CD. The analysis compared a selection of pre-test probabilities of CD above which patients should be screened, as well as the use of different serological tests, with or without genetic testing. Value of information analysis was used to prioritize parameters for future research.

RESULTS

Using serological testing alone in adults, immunoglobulin A (IgA) tissue transglutaminase (tTG) at a 1% pre-test probability (equivalent to population screening) was most cost-effective. If combining serological testing with genetic testing, human leukocyte antigen combined with IgA tTG at a 5% pre-test probability was most cost-effective. In children, the most cost-effective strategy was a 10% pre-test probability with human leukocyte antigen plus IgA tTG. Value of information analysis highlighted the probability of late diagnosis of CD and the accuracy of serological tests as important parameters. The analysis also suggested prioritizing research in adult women over adult men or children.

CONCLUSIONS

For adults, these cost-effectiveness results suggest UK National Screening Committee Criteria for population-based screening for CD should be explored. Substantial uncertainty in the results indicate a high value in conducting further research.

Validation of no-biopsy pathway for the diagnosis of celiac disease in Asian adults: a multicenter retrospective study

BACKGROUND AND AIM

While European Society of Pediatric Gastroenterology Hepatology and Nutrition advocates a no-biopsy pathway for the diagnosis of celiac disease (CeD) in children if IgA anti-tissue transglutaminase antibody (anti-tTG ab) titer is ≥10-fold upper limit of normal (ULN) and have a positive IgA anti-endomysial antibody (EMA); the data for anti-tTG Ab titer-based diagnosis of CeD in adults is still emerging. We planned to validate if IgA anti-tTG Ab titer ≥10-fold predicts villous abnormalities of modified Marsh grade ≥2 in Asian adult patients with CeD.

METHODS

We recruited 937 adult patients with positive anti-tTG Ab from two databases, including AIIMS Celiac Clinic and Indian National Biorepository. The diagnosis of definite CeD was made on the basis of a positive anti-tTG Ab and the presence of villous abnormalities of modified Marsh grade ≥2.

RESULTS

Of 937 adult patients with positive anti-tTG Ab, 889 (91.2%) showed villous abnormalities of modified Marsh grade ≥2. Only 47.6% of 889 adults with CeD had anti- tTG Ab titers of ≥10-fold. The positive predictive value (PPV) and specificity of anti tTG Ab titer ≥10-fold for predicting modified Marsh grade ≥2 were 99.8% and 98%, respectively. At anti-tTG Ab titer ≥11-fold, specificity and PPV were 100% for predicting villous abnormalities of modified Marsh grade ≥2.

CONCLUSIONS

Approximately 50% of adults with CeD may benefit from the no biopsy pathway, reducing the health burden and risks of gastroscopy/anesthesia.

Trends in the prevalence rates and predictive factors of coeliac disease: A long-term nationwide follow-up study

BACKGROUND

The prevalence of coeliac disease doubled in Finland from 1980 to 2000.

AIMS

To investigate whether this increase is continuing and if there are specific patient-related factors predicting the development of coeliac disease at a population level.

METHODS

We elicited comprehensive health data in the nationwide Health 2000 and Health 2011 surveys. Serum samples were taken for the measurement of tissue transglutaminase antibodies (TGA); subjects who were seropositive were tested for endomysial antibodies (EmA). Coeliac disease was defined either as a reported diagnosis or as positive TGA and EmA. The surveys comprised, respectively, 6379 and 4056 individuals, forming representative samples for 2,946,057 and 2,079,438 Finnish adults. Altogether 3254 individuals participating in both surveys comprised a prospective follow-up cohort.

RESULTS

Prevalence of coeliac disease was 2.12% in 2000 and 2.40% in 2011 (p = 0.156). In the prospective cohort, 16 out of the 3254 (0.49%) subjects developed coeliac disease during follow-up from 2000 to 2011, with an annual incidence rate of 45 per 100,000 persons. Positive TGA without EmA (OR: 133, 95% CI: 30.3-584), TGA values in the upper normal range (51.1, 16.0-163), and after adjusting for TGA, previous autoimmune co-morbidity (8.39, 4.98-35.9) in 2000 increased the likelihood of subsequent coeliac disease.

CONCLUSIONS

The nationwide prevalence of coeliac disease kept on rising from 2.12% in 2000 to 2.40% in 2011 in Finland. Positive TGA without EmA, TGA titres in the upper normal range and a pre-existing autoimmune disease predisposed to coeliac disease during the 10-year follow-up.

The strategic use of biopsy in the diagnosis of coeliac disease in adults

BACKGROUND

The paediatric guidelines support the use of the 'No Biopsy Approach' in the diagnosis of coeliac disease (CD). We aimed to determine the correlation between anti tissue transglutaminase (anti-TTG serology) ≥10 times the upper limit of normal (ULN), using the Celikey ® ELiA assay and histological findings. Our secondary aim was to determine the safety of this approach in our centre.

METHODS

A retrospective analysis of adult patients referred to a tertiary referral centre with raised anti-TTG titres and/or histological changes of coeliac on D2 biopsies between 2014 - 2019. Excluded patients were those who did not have a biopsy performed, or whose biopsy was unavailable for review, selective IgA deficiency, and gluten elimination prior to biopsy. Biopsies were classified according to Marsh, by two independent pathologists, blinded to the anti-TTG titre.

RESULTS

164 patients had positive anti-TTG serology and duodenal biopsy in our centre prior to starting a gluten free diet (GFD) in the period 2014 - 2019. Of these 164 patients (median age 40yrs, 62% female), 68 (33%) had an anti-TTG titre ≥10 x ULN, 99% of which had a Marsh grading ≥ 3 and 1% had a Marsh of 2 on biopsy. 91% had either a normal index gastroscopy or findings of mild gastritis/oesophagitis.

CONCLUSIONS

We found a 98.5% positive predictive value (PPV) of determining CD (i.e., Marsh ≥ 3) in those with an anti-TTG ≥10 x ULN. In those with moderate to high-risk clinical suspicion of CD we propose that duodenal biopsy is unnecessary for diagnosis.

Serum anti-tissue transglutaminase IgA and prediction of duodenal villous atrophy in adults with suspected coeliac disease without IgA deficiency (Bi.A.CeD): a multicentre, prospective cohort study

BACKGROUND

Whether coeliac disease in adults can be diagnosed with serology alone remains controversial. We aimed to evaluate the accuracy of serum anti-tissue transglutaminase IgA (tTG-IgA) in the diagnosis of coeliac disease.

METHODS

In this multicentre, prospective cohort study, adult participants (aged ≥18 years) with suspected coeliac disease without IgA deficiency who were not on a gluten-free diet and who had a local serum tTG-IgA measurement, were enrolled from Feb 27, 2018, to Dec 24, 2020, by 14 tertiary referral centres (ten from Europe, two from Asia, one from Oceania, and one from South America) to undergo local endoscopic duodenal biopsy. Local serum tTG-IgA was measured with 14 different test brands and concentration expressed as a multiple of each test's upper limit of normal (ULN), and defined as positive when greater than 1 times the ULN. The main study outcome was the reliability of serum tests for the diagnosis of coeliac disease, as defined by duodenal villous atrophy (Marsh type 3 or Corazza-Villanacci grade B). Histology was evaluated by the local pathologist, with discordant cases (positive tTG-IgA without duodenal villous atrophy or negative tTG-IgA with duodenal villous atrophy) re-evaluated by a central pathologist. The reliability of serum tests for the prediction of duodenal villous atrophy was evaluated according to sensitivity, specificity, positive predictive value, negative predictive value, and the area under the receiver operating characteristic curve (AUC) for categorical and continuous data.

FINDINGS

We enrolled 436 participants with complete local data on serum tTG-IgA and duodenal histology (296 [68%] women and 140 [32%] men; mean age 40 years [SD 15]). Positive serum tTG-IgA was detected in 363 (83%) participants and negative serum tTG-IgA in 73 (17%). Of the 363 participants with positive serum tTG-IgA, 341 had positive histology (true positives) and 22 had negative histology (false positives) after local review. Of the 73 participants with negative serum tTG-IgA, seven had positive histology (false negatives) and 66 had negative histology (true negatives) after local review. The positive predictive value was 93·9% (95% CI 89·2-98·6), the negative predictive value was 90·4% (85·5-95·3), sensitivity was 98·0% (95·3-100·0), and specificity was 75·0% (66·6-83·4). After central re-evaluation of duodenal histology in 29 discordant cases, there were 348 true positive cases, 15 false positive cases, 66 true negative cases, and seven false negative cases, resulting in a positive predictive value of 95·9% (92·0-99·8), a negative predictive value of 90·4% (85·5-95·3), a sensitivity of 98·0% (95·3-100·0), and a specificity of 81·5% (73·9-89·1). Either using the local or central definition of duodenal histology, the positive predictive value of local serum tTG-IgA increased when the serological threshold was defined at increasing multiples of the ULN (p<0·0001). The AUC for serum tTG-IgA for the prediction of duodenal villous atrophy was 0·87 (95% CI 0·81-0·92) when applying the categorical definition of serum tTG-IgA (positive [>1 × ULN] vs negative [≤1 × ULN]), and 0·93 (0·89-0·96) when applying the numerical definition of serum tTG-IgA (multiples of the ULN). Additional endoscopic findings included peptic gastritis (nine patients), autoimmune atrophic gastritis (three), reflux oesophagitis (31), gastric or duodenal ulcer (three), and Barrett's oesophagus (one). In the 1-year follow-up, a midgut ileum lymphoma was diagnosed in a woman on a gluten-free diet.

INTERPRETATION

Our data showed that biopsy could be reasonably avoided in the diagnosis of coeliac disease in adults with reliable suspicion of coeliac disease and high serum tTG-IgA.

FUNDING

None.

Multicenter study to compare the diagnostic performance of CLIA vs. FEIA transglutaminase IgA assays for the diagnosis of celiac disease

OBJECTIVES

Celiac disease (CD) is an immune-mediated enteropathy driven by gluten intake. Presence of tTG-IgA antibodies is important for the diagnosis. However, different tTG-IgA assays are used and test performance may vary. Therefore, a retrospective multicenter study was performed to compare the diagnostic performance of three assays.

METHODS

The fluorescence enzyme-linked immunoassay (FEIA) EliA Celikey IgA (Phadia), the chemiluminescence immunoassays (CLIA) h-tTG IgA QUANTA Flash® (Inova Diagnostics) and the anti-tTG ChLIA IgA (Euroimmun) were compared. Diagnostic samples from CD cases (95 adults; 65 children) and controls (479 adults; 253 children) were included. Samples were blinded and reanalyzed on all platforms.

RESULTS

A high quantitative correlation between platforms was found (p<0.0001). Both CLIA were more sensitive (adults 100%; children 100%) compared to the FEIA (adults 88.4%; children 96.6%). Specificity of all assays was high (≥97.6%) with the FEIA having the highest specificity. A cut-off based on receiver operator characteristic analysis (6.5 U/mL) improved the sensitivity of the FEIA (adults 95.8%; children 100%) without affecting specificity. Cut-off values for the CLIA assays did not need further optimization. With the FEIA, 71% of pediatric cases had a tTG-IgA level ≥10× upper limit of normal compared to 91 and 92% with QUANTA Flash and ChLIA, respectively.

CONCLUSIONS

All platforms have high diagnostic accuracy. The CLIA assays are more sensitive compared to the FEIA assay. A lower cut-off for the FEIA improves diagnostic performance, particularly in adult cases that, as demonstrated in this study, present with lower tTG-IgA levels compared to pediatric cases.

The role of gluten challenge in the diagnosis of celiac disease: a review

INTRODUCTION

Duodenal biopsy is the gold standard in the diagnosis of celiac disease, with increasing utilization of serology. A gluten challenge may be required, for example, when dietary gluten reduction precedes appropriate diagnostic evaluations. Evidence on the best challenge protocol is currently sparse. Pharmaceutical trials in recent years may have provided new insights into the challenge and advanced the development of novel sensitive histological and immunological methods.

AREAS COVERED

This review outlines the current perspectives on the use of gluten challenge in the diagnosis of celiac disease and explores future directions in this area.

EXPERT OPINION

Comprehensive elimination of celiac disease before dietary gluten restriction is essential to avoid diagnostic uncertainties. Gluten challenge continues to have an important role in certain clinical scenarios, although it is important to understand its limitations in the diagnostic evaluation. The evidence so far permits no unequivocal recommendation considering the timing, duration, and amount of gluten used in the challenge. Thus, these decisions should be made on a case-by-case basis. Further studies with more standardized protocols and outcome measures are called for. In the future novel immunological methods may help to shorten or even avoid gluten challenge.

The debate in the diagnosis of coeliac disease - time to go 'no-biopsy'?

PURPOSE OF REVIEW

Duodenal biopsies have been central to making a diagnosis of coeliac disease for the last 70 years. Recent paediatric guidelines have reduced the emphasis on duodenal biopsies with the incorporation of a 'no-biopsy' arm to the diagnostic pathway. This review discusses the no-biopsy approach in adults and highlights advances in alternative (non-biopsy) diagnostic modalities in coeliac disease.

RECENT FINDINGS

Evidence suggests that a no-biopsy approach for the diagnosis of adult coeliac disease is accurate. However, a number of factors still favour duodenal biopsy sampling in specific patient groups. Moreover, several factors need to be considered if this pathway is implemented into local gastroenterology services.

SUMMARY

Duodenal biopsies remain an important step in the diagnosis of adult coeliac disease. However, an alternative approach that removes the necessity for biopsies may be an option in selected adults. If further guidelines incorporate this pathway, then efforts should focus on supporting a dialogue between primary and secondary care to facilitate the appropriate implementation of this approach.

Is There a Need to Undertake Conventional Gastroscopy and Biopsy When Making the Diagnosis of Coeliac Disease in Adults?

Celiac disease is a common autoimmune condition characterized by small intestinal inflammation and mucosal damage triggered by an inappropriate immune response to ingested gluten. Gastroscopy and duodenal biopsy are currently the gold standard approach to diagnosing celiac disease in adults. However, the emergence of highly accurate serological tests for celiac disease in the last 2 decades led to a change in the pediatric guidelines to diagnose celiac disease without biopsy in selected patients. Adopting this no-biopsy approach to diagnose celiac disease in adults remains controversial, but the evidence supporting it is growing.

American College of Gastroenterology Guidelines Update: Diagnosis and Management of Celiac Disease

This guideline presents an update to the 2013 American College of Gastroenterology Guideline on the Diagnosis and Management of Celiac Disease with updated recommendations for the evaluation and management of patients with celiac disease (CD). CD is defined as a permanent immune-mediated response to gluten present in wheat, barley, and rye. CD has a wide spectrum of clinical manifestations that resemble a multisystemic disorder rather than an isolated intestinal disease, and is characterized by small bowel injury and the presence of specific antibodies. Detection of CD-specific antibodies (e.g., tissue transglutaminase) in the serum is very helpful for the initial screening of patients with suspicion of CD. Intestinal biopsy is required in most patients to confirm the diagnosis. A nonbiopsy strategy for the diagnosis of CD in selected children is suggested and discussed in detail. Current treatment for CD requires strict adherence to a gluten-free diet (GFD) and lifelong medical follow-up. Most patients have excellent clinical response to a GFD. Nonresponsive CD is defined by persistent or recurrent symptoms despite being on a GFD. These patients require a systematic workup to rule out specific conditions that may cause persistent or recurrent symptoms, especially unintentional gluten contamination. Refractory CD is a rare cause of nonresponsive CD often associated with poor prognosis.

Expression of tolerogenic dendritic cells in the small intestinal tissue of patients with celiac disease

Tolerogenic dendritic cells (tolCDs) play an important role in the regulation of inflammation in autoimmune diseases such as celiac disease (CeD). Dendritic cells express CD207, CD11c, and CD103 on their surface. In addition to the receptors mentioned above, tolCDs can express the immune-regulating enzyme indoleamine 2,3-dioxygenase (IDO). This study aimed to determine the mRNA and protein expression of CD11c, CD103 and CD207 markers, and also IDO gene expression in intestinal tissues of CeD patients in comparison to the healthy individuals. Duodenal biopsies were collected from 60 CeD patients and 60 controls. Total RNA was extracted and gene expression analysis was performed using Real-time PCR SYBR® Green method. Additionally, biopsy specimens were paraffinized and protein expression was evaluated using immunohistochemistry (IHC) for expression of CD11c+, CD207+and CD103+. Gene expression levels of CD11c (P = 0.045), CD103 (P < 0.001), CD207 (P < 0.001) and IDO (P = 0.01) were significantly increased in CeD patients compared to the control group. However, only CD103 protein expression was found to be significantly higher in CeD patients in comparison to the control group (P < 0.001). The result of this study showed that the expresion levels of CD11c, CD103, CD207 and IDO markers were higher in CeD patients compared to the controls, indicating the effort of dendritic cells to counterbalance the gliadin-triggered abnormal immune responses in CeD patients.

Upper gastrointestinal endoscopic findings in celiac disease at diagnosis: A multicenter international retrospective study

BACKGROUND

Gastroduodenal endoscopy and biopsy following positive specific serology is considered the gold standard to diagnose celiac disease (CeD) in adults. Whether upper endoscopy helps detect comorbid conditions is unknown.

AIM

To investigate the prevalence of non-celiac endoscopic findings in patients in whom endoscopy was performed to confirm CeD diagnosis.

METHODS

This is an observational, descriptive, multicenter, retrospective study that reports endoscopic findings obtained in adult patients enrolled in local registries from four tertiary centers. We collected data reported on first endoscopy, indicated for investigation of CeD. Diagnosis of CeD was performed by histology (≥ Marsh 2 type mucosal damage) and specific serology. Two European and one North American center included biopsy-confirmed CeD following positive serology. A fourth center (South America) included symptomatic patients undergoing endoscopy, irrespective of CeD serology. The latter cohort included a non-CeD control group.

RESULTS

A total of 1328 patients (80% female; 35 years median age) were enrolled, of whom 95.6% had positive specific serology. In 135 patients, endoscopy revealed 163 abnormalities unrelated to CeD (prevalence: 10.1%). Erosive reflux esophagitis (6.4%), gastric erosions (2.0%), and suspicion of esophageal metaplasia (1.2%) were the most common findings. Biopsy-confirmed Barrett’s esophagus was infrequent (0.2%). No endoscopic cancer was detected. Older patients (≥ 51 years of age) had a higher prevalence of endoscopic findings than those ≤ 50 (P < 0.01). Within the South American cohort, CeD was associated with a lower rate (8.2%) of comorbid endoscopic findings compared with controls (29.1%; P < 0.001). In the adjusted multivariate analysis of this cohort, having CeD was associated with a 72% reduction in the risk of any endoscopic abnormality (P < 0.0001), and having alarm symptoms was associated with a 37% reduction in the risk of finding at least one endoscopic lesion (P < 0.02).

CONCLUSION

In this large multicenter study, young adults with positive CeD serology had few comorbid endoscopic findings. Although patients over 51 years had a high prevalence of non-CeD gastroduodenal mucosal damage, no malignancy or premalignant lesions were found.

High Prevalence of Functional Gastrointestinal Disorders in Celiac Patients with Persistent Symptoms on a Gluten-Free Diet: A 20-Year Follow-Up Study

BACKGROUND

Ongoing symptoms in treated celiac disease (CD) are frequent and are commonly thought of as being due to infractions to a gluten-free diet (GFD) or complications.

AIMS

To study the etiology and natural history of clinically relevant events (CREs) throughout follow-up and identify predictors thereof to guide follow-up.

METHODS

CREs (symptoms/signs requiring diagnostic/therapeutic interventions) occurring in celiac patients between January-2000 and May-2021 were retrospectively collected between June and September 2021 and analysed.

RESULTS

One-hundred-and-eighty-nine adult patients (133 F, age at diagnosis 36 ± 13 years, median follow-up 103 months, IQR 54-156) were enrolled. CREs were very common (88/189, 47%), but hardly due to poor GFD adherence (4%) or complications (2%). Interestingly, leading etiologies were functional gastrointestinal disorders (30%), reflux disease (18%) and micronutrient deficiencies (10%). Age at diagnosis ≥ 45 years (HR 1.68, 95%CI 1.05-2.69, p = 0.03) and classical pattern of CD (HR 1.63, 95%CI 1.04-2.54, p = 0.03) were predictors of CREs on a multivariable Cox model. At 5 years, 46% of classical patients ≥ 45 years old at diagnosis were event-free, while this was 62% for non-classical/silent ≥ 45 years, 60% for classical < 45 years, and 80% for non-classical/silent < 45 years.

CONCLUSIONS

CREs occurred in almost half of CD patients during follow-up, with functional disorders being very common. New follow-up strategies for adult CD may be developed based on age and clinical pattern at diagnosis.

Defining the optimum strategy for identifying adults and children with coeliac disease: systematic review and economic modelling

BACKGROUND

Coeliac disease is an autoimmune disorder triggered by ingesting gluten. It affects approximately 1% of the UK population, but only one in three people is thought to have a diagnosis. Untreated coeliac disease may lead to malnutrition, anaemia, osteoporosis and lymphoma.

OBJECTIVES

The objectives were to define at-risk groups and determine the cost-effectiveness of active case-finding strategies in primary care.

DESIGN

(1) Systematic review of the accuracy of potential diagnostic indicators for coeliac disease. (2) Routine data analysis to develop prediction models for identification of people who may benefit from testing for coeliac disease. (3) Systematic review of the accuracy of diagnostic tests for coeliac disease. (4) Systematic review of the accuracy of genetic tests for coeliac disease (literature search conducted in April 2021). (5) Online survey to identify diagnostic thresholds for testing, starting treatment and referral for biopsy. (6) Economic modelling to identify the cost-effectiveness of different active case-finding strategies, informed by the findings from previous objectives.

DATA SOURCES

For the first systematic review, the following databases were searched from 1997 to April 2021: MEDLINE® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, the Netherlands), Cochrane Library, Web of Science™ (Clarivate™, Philadelphia, PA, USA), the World Health Organization International Clinical Trials Registry Platform ( WHO ICTRP ) and the National Institutes of Health Clinical Trials database. For the second systematic review, the following databases were searched from January 1990 to August 2020: MEDLINE, Embase, Cochrane Library, Web of Science, Kleijnen Systematic Reviews ( KSR ) Evidence, WHO ICTRP and the National Institutes of Health Clinical Trials database. For prediction model development, Clinical Practice Research Datalink GOLD, Clinical Practice Research Datalink Aurum and a subcohort of the Avon Longitudinal Study of Parents and Children were used; for estimates for the economic models, Clinical Practice Research Datalink Aurum was used.

REVIEW METHODS

For review 1, cohort and case-control studies reporting on a diagnostic indicator in a population with and a population without coeliac disease were eligible. For review 2, diagnostic cohort studies including patients presenting with coeliac disease symptoms who were tested with serological tests for coeliac disease and underwent a duodenal biopsy as reference standard were eligible. In both reviews, risk of bias was assessed using the quality assessment of diagnostic accuracy studies 2 tool. Bivariate random-effects meta-analyses were fitted, in which binomial likelihoods for the numbers of true positives and true negatives were assumed.

RESULTS

People with dermatitis herpetiformis, a family history of coeliac disease, migraine, anaemia, type 1 diabetes, osteoporosis or chronic liver disease are 1.5-2 times more likely than the general population to have coeliac disease; individual gastrointestinal symptoms were not useful for identifying coeliac disease. For children, women and men, prediction models included 24, 24 and 21 indicators of coeliac disease, respectively. The models showed good discrimination between patients with and patients without coeliac disease, but performed less well when externally validated. Serological tests were found to have good diagnostic accuracy for coeliac disease. Immunoglobulin A tissue transglutaminase had the highest sensitivity and endomysial antibody the highest specificity. There was little improvement when tests were used in combination. Survey respondents (n = 472) wanted to be 66% certain of the diagnosis from a blood test before starting a gluten-free diet if symptomatic, and 90% certain if asymptomatic. Cost-effectiveness analyses found that, among adults, and using serological testing alone, immunoglobulin A tissue transglutaminase was most cost-effective at a 1% pre-test probability (equivalent to population screening). Strategies using immunoglobulin A endomysial antibody plus human leucocyte antigen or human leucocyte antigen plus immunoglobulin A tissue transglutaminase with any pre-test probability had similar cost-effectiveness results, which were also similar to the cost-effectiveness results of immunoglobulin A tissue transglutaminase at a 1% pre-test probability. The most practical alternative for implementation within the NHS is likely to be a combination of human leucocyte antigen and immunoglobulin A tissue transglutaminase testing among those with a pre-test probability above 1.5%. Among children, the most cost-effective strategy was a 10% pre-test probability with human leucocyte antigen plus immunoglobulin A tissue transglutaminase, but there was uncertainty around the most cost-effective pre-test probability. There was substantial uncertainty in economic model results, which means that there would be great value in conducting further research.

LIMITATIONS

The interpretation of meta-analyses was limited by the substantial heterogeneity between the included studies, and most included studies were judged to be at high risk of bias. The main limitations of the prediction models were that we were restricted to diagnostic indicators that were recorded by general practitioners and that, because coeliac disease is underdiagnosed, it is also under-reported in health-care data. The cost-effectiveness model is a simplification of coeliac disease and modelled an average cohort rather than individuals. Evidence was weak on the probability of routine coeliac disease diagnosis, the accuracy of serological and genetic tests and the utility of a gluten-free diet.

CONCLUSIONS

Population screening with immunoglobulin A tissue transglutaminase (1% pre-test probability) and of immunoglobulin A endomysial antibody followed by human leucocyte antigen testing or human leucocyte antigen testing followed by immunoglobulin A tissue transglutaminase with any pre-test probability appear to have similar cost-effectiveness results. As decisions to implement population screening cannot be made based on our economic analysis alone, and given the practical challenges of identifying patients with higher pre-test probabilities, we recommend that human leucocyte antigen combined with immunoglobulin A tissue transglutaminase testing should be considered for adults with at least a 1.5% pre-test probability of coeliac disease, equivalent to having at least one predictor. A more targeted strategy of 10% pre-test probability is recommended for children (e.g. children with anaemia).

FUTURE WORK

Future work should consider whether or not population-based screening for coeliac disease could meet the UK National Screening Committee criteria and whether or not it necessitates a long-term randomised controlled trial of screening strategies. Large prospective cohort studies in which all participants receive accurate tests for coeliac disease are needed.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42019115506 and CRD42020170766.

FUNDING

This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 44. See the NIHR Journals Library website for further project information.

No-biopsy strategy for coeliac disease is applicable in adult patients: a 'real-world' Scottish experience

Objective

Emergency interim guidance from the British Society for Gastroenterology (BSG) states that a no-biopsy strategy is possible to diagnose coeliac disease (CD) in adults with elevated transglutaminase IgA antibody (TGA-IgA) levels. We aimed to determine if the suggested TGA-IgA ≥10× ULN is safe and robust in making the diagnosis in adult patients in Scotland. We also aimed to establish if any important co-diagnoses would be missed if no biopsy was performed.

Method

All positive coeliac serology results for patients aged >15 years in Scotland in 2016 (Grampian 2019) were accessed. Data were collected on demographics, TGA-IgA titres, D1 sampling, histology and macroscopic findings at upper and lower gastrointestinal (GI) endoscopy.

Results

1037/1429 patients with positive serology proceeded to biopsy, of which 796/1037 (76.8%) were diagnosed as CD. A total of 320/322 (99.37%) patients with TGA-IgA ≥10× ULN were diagnosed as CD giving the cut-off a positive predictive value of 99.38%. No significant co-pathology was found at endoscopy in these patients.

Conclusion

Our results show that a no-biopsy strategy using a cut-off of TGA-IgA ≥10× ULN is safe to diagnose CD and that no important pathology would be missed. The European Society for Paediatric Gastroenterology, Hepatology and Nutrition 2020 and BSG COVID-19 interim guidelines are applicable to adult patients in Scotland.

Review article: Diagnosis of coeliac disease: a perspective on current and future approaches

Diagnostics will play a central role in addressing the ongoing dramatic rise in global prevalence of coeliac disease, and in deploying new non-dietary therapeutics. Clearer understanding of the immunopathogenesis of coeliac disease and the utility of serology has led to partial acceptance of non-biopsy diagnosis in selected cases. Non-biopsy diagnosis may expand further because research methods for measuring gluten-specific CD4+ T cells and the acute recall response to gluten ingestion in patients is now relatively straightforward. This perspective on diagnosis in the context of the immunopathogenesis of coeliac disease sets out to highlight current consensus, limitations of current practices, gluten food challenge for diagnosis and the potential for diagnostics that measure the underlying cause for coeliac disease, gluten-specific immunity.

Impact of COVID-19 pandemic on pediatric endoscopy: A multicenter study on behalf of the SIGENP Endoscopy Working Group

BACKGROUND

Aim of the present report was to investigate the repercussions of COVID-19 pandemic on the procedural volumes and on the main indications of pediatric digestive endoscopy in Italy.

METHODS

An online survey was distributed at the beginning of December 2020 to Italian digestive endoscopy centers. Data were collected comparing two selected time intervals: the first from 1st of February 2019 to 30th June 2019 and the second from 1st February 2020 to 30th June 2020.

RESULTS

Responses to the survey came from 24 pediatric endoscopy Units. Globally, a reduction of 37.2% was observed between 2019 and 2020 periods with a significant decrease in median number of procedures (111 vs 57, p < 0.001). Both the median number of procedures performed for new diagnoses and those for follow-up purposes significantly decreased in 2020 (63 vs 36, p < 0.001 and 42 vs 21, p< 0.001, respectively). We reported a drastic reduction of procedures performed for suspected Celiac Disease and Functional Gastrointestinal Disorders (55.1% and 58.0%, respectively). Diagnostic endoscopies for suspected IBD decreased of 15.5%, whereas procedures for Mucosal Healing (MH) assessment reduced of 48.3%.

CONCLUSIONS

Our study provides real-world data outlining the meaningful impact of COVID-19 on pediatric endoscopy practice in Italy.

The global burden of coeliac disease: opportunities and challenges

Coeliac disease is a systemic disorder characterized by immune-mediated enteropathy, which is caused by gluten ingestion in genetically susceptible individuals. The clinical presentation of coeliac disease is highly variable and ranges from malabsorption through solely extra-intestinal manifestations to asymptomatic. As a result, the majority of patients with coeliac disease remain undiagnosed, misdiagnosed or experience a substantial delay in diagnosis. Coeliac disease is diagnosed by a combination of serological findings of disease-related antibodies and histological evidence of villous abnormalities in duodenal biopsy samples. However, variability in histological grading and in the diagnostic performance of some commercially available serological tests remains unacceptably high and confirmatory assays are not readily available in many parts of the world. Currently, the only effective treatment for coeliac disease is a lifelong, strict, gluten-free diet. However, many barriers impede patients' adherence to this diet, including lack of widespread availability, high cost, cross-contamination and its overall restrictive nature. Routine follow-up is necessary to ensure adherence to a gluten-free diet but considerable variation is evident in follow-up protocols and the optimal disease management strategy is not clear. However, these challenges in the diagnosis and management of coeliac disease suggest opportunities for future research.

Celiac Disease Revisited

Celiac disease (CD) is a systemic disease triggered by gluten ingestion in genetically predisposed individuals. It manifests primarily as an autoimmune enteropathy associated with specific circulating autoantibodies and a human leukocyte antigen haplotype (HLA-DQ2 or HLA-DQ8). It afflicts roughly 1% of the population, though the majority of patients remain undiagnosed. Diarrhea and malabsorption are classic manifestations of CD; however, both children and adults can be paucisymptomatic and present extraintestinal manifestations such as anemia, osteoporosis, and abnormal liver tests. CD screening is not recommended for the general population, and it should be focused on high-risk groups. CD diagnosis is challenging and relies on serological tests, duodenal histology, and genetic testing. Particularly difficult presentations to manage are seronegative patients, seropositive patients without villus atrophy, and patients who have started a gluten-free diet before the diagnostic workup. The only proven treatment is a lifelong gluten-free diet. We present an in-depth review on the physiopathology and management of CD, with a particular emphasis on diagnostic challenges.

Upper Gastrointestinal Tract Associated Lesions in Patients with Newly Diagnosed Celiac Disease

(1) Background: Currently available guidelines require upper gastrointestinal (GI) endoscopy with biopsy sampling for adult celiac disease (CD) diagnosis. Based on the pediatric experience, there has been a growing interest if serology-based diagnosis would be possible for adult CD also. Our aim was to analyze the associated upper GI tract lesions in newly diagnosed CD patients, to see if significant associated pathology is detected during index endoscopy, which might impact patient management not related to CD. (2) Methods: We performed a retrospective analysis of newly diagnosed CD cases diagnosed over a period of 7 years (2014–2020). Demographic, clinical, laboratory, endoscopy and histopathology data were collected from the patients’ charts. Diagnosis was set according to ACG Guideline 2013. (3) Results: Altogether 79 patients were recruited for this study purpose, 75.9% female, median age 39 years. All patients had positive CD-specific serology and atrophic mucosal injury in duodenal biopsy samples. Besides villous atrophy, associated endoscopic findings were detected in 42/79 (53.16%) of patients. Most of the gastric lesions were minor endoscopic findings—small sliding hiatal hernias, non-specific chronic gastritis, but we also found two cases of peptic ulcers, one case of metaplastic gastritis, six cases of atrophic gastritis and one subepithelial lesion. Only one patient had changes in the duodenum except CD-related findings—an inflammatory polyp in the duodenal bulb. No malignancies were found. (4) Conclusions: In our cohort, there was a significant number of newly diagnosed CD patients who had associated lesions during the index upper GI endoscopy, but most of them were minor endoscopic findings.

Enfermedad celíaca: un reto diagnóstico en Colombia

Introducción: la enfermedad celíaca (EC) es una patología sistémica inmunomediada por el gluten en la dieta en personas genéticamente susceptibles con un amplio rango de manifestaciones clínicas, respuesta serológica específica y daño variable de la mucosa intestinal. Objetivo: revisar la fisiopatología, manifestaciones clínicas, diagnóstico, tratamiento, seguimiento y pronóstico de la EC, resaltando la importancia de reconocerla y proponer un algoritmo diagnóstico para la población colombiana. Materiales y métodos: revisión crítica de la literatura científica en las bases de datos Medline y buscadores específicos PUBMED, SCIENCE DIRECT, SCIELO, filtrando resultados a revisiones sistemáticas, metaanálisis, ensayos controlados aleatorios, ensayos clínicos y guías, con un total de 1209 artículos, de los cuales se priorizaron 53. Resultados y discusión: la prevalencia de la EC viene en aumento en países en vía de desarrollo. El diagnóstico tiene tres pilares fundamentales: identificación de casos de alto riesgo o sospecha por manifestaciones clínicas, perfil serológico de anticuerpos específicos y hallazgos histológicos característicos. El tratamiento se basa en dieta sin gluten, detección temprana de complicaciones y manejo de las alteraciones nutricionales. Conclusión: en Colombia no existen protocolos de diagnóstico y tratamiento de la EC, como tampoco una legislación clara con respecto al etiquetado de productos libres de gluten. Hay que establecer estrategias para impactar el curso natural de la enfermedad, las morbilidades asociadas y la calidad de vida de los pacientes.

May Antitransglutaminase Levels Predict Severity of Duodenal Lesions in Adults with Celiac Disease?

Background and Objective: Pediatric guidelines on celiac disease (CD) state that children with anti-transglutaminase antibodies (TGAs) >×10 upper limit of normal (ULN) may avoid endoscopy and biopsy. We aimed to evaluate whether these criteria may be suitable for villous atrophy diagnosis in CD adults. Materials and Methods: We retrospectively enrolled patients with CD aged >18 years. TGAs were expressed as xULN. Duodenal lesions were classified as atrophic or non-atrophic according to Marsh-Oberhuber. Fisher’s exact and t-test were used for variables comparison. Receiver operating characteristics (ROC) curve analysis was performed with estimation of area under the curve (AUC), sensitivity, specificity, and positive and negative predictive value (PPV/NPV). Results: One hundred and twenty-one patients were recruited. Sixty patients (49.6%) had TGA >×10 ULN, and 93 (76.8%) had villous atrophy. The cut-off of >×10 ULN had sensitivity = 53.7%, specificity = 64.3%, PPV = 83.3%, and NPV = 29.5% to predict atrophy. Therefore, considering pediatric criteria, in 50 (41.3%) patients, biopsy could have been avoided. Patient subgroup with atrophy had higher TGA levels despite being not significant (37.2 ± 15.3 vs. 8.0 ± 1.3 ULN, p = 0.06). In adults, a slightly better diagnostic performance was obtained using a cut-off of TGA >×6.2 ULN (sensitivity = 57.1%, specificity = 65.6%, and AUC = 0.62). Conclusions: Despite our confirmation that villous atrophy is linked to high TGA levels, CD and atrophy diagnosis based only on serology is not reliable in adults.

Letter: the BSG COVID-19 interim coeliac disease guidance no-biopsy approach is safe in adults

This article is linked to Paul et al paper. To view this article, visit https://doi.org/10.1111/apt.16133

Presence of high-risk HLA genotype is the most important individual risk factor for coeliac disease among at-risk relatives

BACKGROUND

Family screening has been advocated as a means to reduce the major underdiagnosis of coeliac disease. However, the precise risk of the disease in relatives and the impact of patient- and relative-related individual factors remain obscure.

AIMS

To investigate the individual risk of coeliac disease among patients' relatives.

METHODS

Altogether 2943 relatives of 624 index patients were assessed for the presence of previous coeliac disease diagnosis, or were screened for the disease. Coeliac disease-associated human leucocyte antigen (HLA) genotype was determined from all participants. The association between individual factors and new screening positivity was assessed by logistic regression.

RESULTS

There were 229 previously diagnosed non-index relatives with coeliac disease and 2714 non-affected (2067 first-degree, 647 more distant) relatives. Of these 2714 relatives, 129 (4.8%) were screening-positive (first-degree 5.1%, second-degree 3.6%, more distant 3.5%). The combined prevalence of the previously diagnosed and now detected cases in relatives was 12.2% (6.3% clinically detected, 5.9% screen-detected). In univariate analysis, age <18 years at diagnosis (odds ratio 1.60, 95% CI 1.04-2.45) in index, and age 41-60 years (1.73, 1.10-2.73), being a sibling (1.65, 1.06-2.59) and having the high-risk genotype (3.22, 2.01-5.15 DQ2.5/2.5 or DQ2.5/2.2 vs other risk alleles) in relatives were associated with screening positivity. Only high-risk HLA remained significant (2.94, 1.80-4.78) in multivariable analysis.

CONCLUSIONS

Unrecognised coeliac disease was common among at-risk relatives even in a country with an active case-finding policy, and also in relatives more distant than first-degree. The presence of a high-risk genotype was the most important predictor for screening positivity. ClinicalTrials.gov identifier NCT03136731.

Modern understanding of adult celiac disease

The article presents a modern view of celiac disease within the framework of the classification concept of gluten- associated disorders. The prevalence of the disease, the modern model of the etiopathogenesis of celiac disease, clinical manifestations, and the possibilities of differential diagnosis are discussed. According to the European guidelines, a strategy for monitoring outpatients with celiac disease is presented, based on baseline characteristics of the disease, regular doctor- patient interaction, and prevention of gluten- associated disorders.

Is duodenal biopsy always necessary for the diagnosis of coeliac disease in adult patients with high anti-tissue transglutaminase (TTG) antibody titres?

OBJECTIVE

Avoiding duodenal biopsy in adults for coeliac disease (CD) diagnosis is controversial. Some retrospective and prospective studies have shown that CD can be reliably diagnosed in adults with serology rather than duodenal biopsies. This study aimed to check the accuracy of a cut-off value of ≥10 upper limit of normal of anti-tissue transglutaminase antibody (anti-TTG IgA) titres for CD diagnosis in adult patients.

METHOD

We retrospectively analysed adult patients (≥16 years) who underwent gastroscopy from 2013 to 2018 for positive coeliac serology. The relationship between titres and disease was determined by using linear models, whereas sensitivity and specificity were assessed by receiver operator curve.

RESULTS

We analysed 144 newly anti-TTG antibody-positive adult patients with a median age of 48.5 years (IQR 32-62); among them, 86 (60%) patients had CD (Marsh III: n=68 and Marsh II and I: n=18) with a higher prevalence in females (n=59 (69%)) and Europeans (n=60 (70%)). Fifty (58%) patients with CD had colonoscopy and five (6%) had imaging; only six patients were diagnosed with additional conditions. An anti-TTG IgA titre cut-off value of 150 U/L was 100% specific for CD in our dataset, with 70% (95% CI: 60% to 88%) sensitivity for this patient group.

CONCLUSION

Coeliac serology using anti-TTG IgA with titres ≥10× normal value is an excellent predictor of CD, irrespective of age, gender and ethnicity. Duodenal biopsy may not be necessary in selected adult patients with CD, especially younger than 50 years of age without additional gastrointestinal red-flag signs and symptoms.

Celiac Disease Management in the United Kingdom Specialist Pediatric Gastroenterology Centers-A Service Survey

OBJECTIVES

The 2012 European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) guidelines on celiac disease (CD) recommended a no-biopsy pathway (NBP) for symptomatic children with high immunoglobin A (IgA)-based anti-tissue transglutaminase (TGA-IgA) titers, positive anti-endomysial antibody and human leukocyte antigen (HLA)-DQ2/DQ8 status. We aimed to understand variations in practice amongst specialist pediatric gastroenterology centers (SPGIC) in the United Kingdom (UK).

METHODS

A survey questionnaire was sent to all UK SPGIC (n = 29) providing endoscopy services for CD diagnosis. It was divided into four main subgroups: analyzing diagnosis of CD through adherence to the ESPGHAN (2012) guidelines, post-diagnosis care and long-term follow-up and discharge from pediatric services.

RESULTS

All 29 responded. NBP was implemented in 28 of 29 centers. Five of 29 centers had already stopped HLA-DQ2/DQ8 testing for NBP diagnosis. Twenty six of 29 centers were performing endoscopy on screening-identified children (mostly asymptomatic, "at-risk" patients). Diagnosis was communicated by a doctor in 65% SPGIC (n = 19). Most centers (n = 23) waited 6-12 months post-diagnosis to start gluten-free oats. Routine vitamin D supplementation was commenced by 4 of 29 centers. All centers repeated TGA-IgA to assess normalization but at varying times post-GFD. Follow-up was with a combination of doctors/dieticians (n = 26). Eleven of 29 centers discharged their patient to primary care.

CONCLUSIONS

There was excellent uptake of ESPGHAN guidelines (2012) in the UK and adherence to guidelines is generally good. Despite published evidence and pragmatic advice from the British Society of Paediatric Gastroenterology Hepatology and Nutrition and National Institute for Health and Care Excellence, significant differences remain in diagnostic and ongoing management practice and are opportunities for research and directive evidence-based follow-up guidance.

Diagnostic Value of Persistently Low Positive TGA-IgA Titers in Symptomatic Children With Suspected Celiac Disease

OBJECTIVES

While the algorithm to diagnose celiac disease (CD) in children with elevated anti-transglutaminase IgA (TGA-IgA) titers (>10 times upper limit of normal, ULN) is well defined, the management of children with low TGA-IgA values represents a clinical challenge. We aimed to identify the diagnostic value of persistently low positive TGA-IgA titers in predicting CD in children.

METHODS

We retrospectively analyzed children with symptoms or signs of CD, not eligible for a no-biopsy approach. We included children with at least 2 TGA-IgA measurements, endomysial antibody (EMA) assessment and esophagogastroduodenoscopy with biopsies. TGA-IgA values were provided as multiples of ULN. Patients were classified in groups according to median TGA-IgA values: A (TGA-IgA>1 ≤ 5 × ULN; defined as "low-positive"), B (TGA-IgA > 5 < 10 × ULN; "moderate-positive"), and C (controls).

RESULTS

Data of 281 children were analyzed. Of 162 children in group A, CD was diagnosed in 142 (87.7%), whereas normal duodenal mucosa was found in 20. In group B, all 62 children (100%) received a CD diagnosis. Group C included 57 controls. EMA were undetectable in 31 (15%) of mucosal atrophy cases. On the receiver-operating characteristic curve (area under the curve = 0.910), a mean value of 1.7 ULN showed a sensitivity of 81.4% and specificity of 81.8% to predict mucosal damage.

CONCLUSIONS

Repeated low or moderate TGA-IgA values (<5 ULN or <10 ULN) are good predictors of a CD diagnosis. Symptomatic children with persistently low positive TGA-IgA titers should undergo esophagogastroduodenoscopy regardless of their EMA status.

Celiac disease antibody levels reflect duodenal mucosal damage but not clinical symptoms

OBJECTIVES

This study aimed to investigate, in a real-world population, whether the histological and clinical phenotype differ at baseline and during follow-up in patients with high and low CD (celiac disease) antibody titers.

MATERIALS AND METHODS

The study cohort consisted of 96 consecutive patients diagnosed to have CD during the years 2010-2018. The clinical parameters, symptoms and laboratory results were registered and histomorphometry was analyzed from the available duodenal biopsies taken during the primary and follow-up esophageal-gastricduodenoscopies. Patients having immunoglobulin A transglutaminase antibody (tTG-ab) levels above 70 U/mL were classified as high titer patients.

RESULTS

Measured by the villous-crypt ratio, the duodenal mucosa was more severely damaged in the high tTG-ab group than in the low tTG-group at baseline (n = 70, 0.61 ± 0.63 vs. 1.02 ± 0.87, p = .003) and during the follow-up when the patients were on gluten-free diet (n = 27, 1.80 ± 0.72 vs. 2.35 ± 0.64, p = .041). Interestingly, the high tTG-ab group members had fewer gastrointestinal symptoms at baseline than those in the low tTG-ab group (43% vs. 68%, p = .013) but lower vitamin D levels (68 ± 34 nmol/L vs. 88 ± 29 nmol/L, p = .034) and more often microcytosis (28% vs. 10%, p = .040). During the follow-up, these differences were no longer detected.

CONCLUSIONS

At baseline, CD patients with high tTG-ab have more severe duodenum injury and signs of malabsorption but fewer symptoms. After gluten-free diet has been initiated, the mucosal healing in the high tTG-ab group is prolonged, but symptoms and signs of malabsorption recover equally in both groups.

The use of peripheral blood mononuclear cells in celiac disease diagnosis and treatment

Introduction: Celiac disease is characterized by an abnormal immune activation driven by the ingestion of gluten from wheat, barley, and rye. Gluten-specific CD4⁺ T cells play an important role in disease pathogenesis and are detectable among peripheral blood mononuclear cells (PBMCs). Areas covered: This review summarizes the use of celiac disease patient PBMCs in clinical applications focusing on their exploitation in the development of diagnostic approaches and novel drugs to replace or complement gluten-free diet. Expert opinion: The most used PBMC-based methods applied in celiac disease research include ELISpot and HLA-DQ:gluten tetramer technology. ELISpot has been utilized particularly in research aiming to develop a celiac disease vaccine and in studies addressing the toxicity of different grains in celiac disease. HLA-DQ:gluten tetramer technology on the other hand initially focused on improving current diagnostics but in combination with additional markers it is also a useful outcome measure in clinical trials to monitor the efficacy of drug candidates. In addition, the technology serves well in the more detailed characterization of celiac disease-specific T cells, thereby possibly revealing novel therapeutic targets. Future studies may also reveal clinical applications for PBMC microRNAs and/or dendritic cells or monocytes present among PBMCs.

Epidemiology, Presentation, and Diagnosis of Celiac Disease

The incidence of celiac disease is increasing, partly because of improved recognition of, and testing for, the disease. The rise in incidence is also due to a real increase of this immune-based disorder, independent of disease detection. The reasons for this true rise in recent decades are unknown but may be related to environmental factors that may promote loss of tolerance to dietary gluten. Strategies to reduce the development of celiac disease have not been proven successful in randomized trials, but the quantity of early-life gluten exposure has been a major focus of prevention efforts. The criteria for the diagnosis of celiac disease are changing, but in adults, diagnosis still depends on the presence of duodenal villous atrophy while the patient is on a gluten-containing diet, along with findings from serology analysis. Although guidelines in the United States continue to mandate a biopsy at all ages, some children receive a diagnosis of celiac disease without a biopsy. If proven accurate and scalable, assays that detect gluten-HLA tetramer complexes might be used in diagnosis to be made in the context of a gluten-free diet without intestinal biopsy.

Prevalence of Inflammatory Bowel Disease and Celiac Disease in Patients with IgA Nephropathy over Time

INTRODUCTION

IgA nephropathy (IgAN) has been connected with increased intestinal permeability and subclinical intestinal mucosal inflammation as well as with inflammatory bowel disease (IBD) and celiac disease - nevertheless, the results are controversial. The prevalence of bowel diseases has increased over time in Western populations. Whether similar trend is seen among IgAN patients remains obscure. Our aim was to study the prevalence of IBD and celiac disease in IgAN patients over time.

METHODS

The study cohort consisted of altogether 629 patients with newly diagnosed IgAN during years 1976-2012. Data on diagnosis of IBD and celiac disease were retrospectively collected from medical records. Further, to detect unrecognized celiac disease, IgA-class tissue transglutaminase antibodies (tTGA) were measured from serum samples taken at the time of kidney biopsy during years 1980-2012 (defined as screen-detected celiac disease autoimmunity).

RESULTS

The prevalence of IBD among IgAN patients increased over time from 0 to 4.4%, while the prevalence of clinically diagnosed celiac disease decreased from 2.6 to 0.6%. Moreover, the number of screen-detected tTGA-positive cases decreased from the 1980s to the 21st century (2.8-0.7%).

CONCLUSION

The prevalence of IBD increased over time in IgAN patients, which exceeds the prevalence of 0.6% in Finnish general population. In parallel, the prevalence of celiac disease and screen-detected celiac disease autoimmunity decreased over time. The coexistence of IBD and IgAN is not negligible. Whether this finding is caused by the increase in the prevalence of IBD in the population or shared pathophysiology between IgAN and IBD remains a matter of further studies.

Coeliac disease and noncoeliac wheat or gluten sensitivity

Coeliac disease (CD) and noncoeliac wheat or gluten sensitivity (NCWS/NCGS) are common gluten-related disorders. Both conditions can present with gastrointestinal and extraintestinal manifestations, which can be a challenge for physicians to discern between. Whilst coeliac serology and histological assessment are required for the diagnosis of CD, there are no clear biomarkers for the diagnosis of NCGS. The management of both conditions is with a gluten-free diet (GFD), although the duration, as well as strictness of adherence to a GFD in NCGS, is unclear. Adherence to a GFD in CD can also be challenging, with recent developments of noninvasive assessments, although histological assessment via duodenal biopsies remains the gold standard. The management of refractory coeliac disease remains particularly challenging, often requiring specialist input. Whilst wheat is noted to be a trigger for symptom generation in NCGS, it is unclear which components of wheat are responsible for symptom generation in this group, with further research required to elucidate the pathophysiology.

Low prevalence of upper endoscopic gastrointestinal findings despite high frequency of alarm symptoms at the time of diagnosis in adult coeliac disease

OBJECTIVES

Exclusion of organic disorders involving the upper gastrointestinal (UGI) is a mandatory step before considering a biopsy-avoidance diagnostic strategy for adult coeliac disease. We aim to evaluate the prevalence of alarm symptoms and coincidental UGI endoscopic findings at the time of diagnosis of coeliac disease. To develop consensus criteria to identify patients with coeliac disease requiring a gastroscopy and to evaluate whether alarm symptoms prompting gastroscopy were predictive of endoscopic findings.

METHODS

Presenting symptoms and UGI endoscopic findings at diagnosis of coeliac disease were collected retrospectively in 278 adult patients with coeliac disease diagnosed in Pavia between January 1999 and December 2017. A panel of experts developed criteria to evaluate which clinical scenarios warrant gastroscopy, which was then applied retrospectively to patients diagnosed in Pavia.

RESULTS

At least one alarm symptom was present in 177/278 patients, 121/278 met our criteria for gastroscopy. Major UGI endoscopic findings included 3 cases of autoimmune atrophic gastritis, 19 oesophagitis and 20 Helicobacter pylori infections. No organic disorders were found. Prevalence of major endoscopic findings did not differ between patients who met our criteria and those who did not.

CONCLUSIONS

Despite the high prevalence of alarm symptoms at diagnosis, coincident major UGI endoscopic findings are rare in adult coeliac disease. These results may be relevant for future developments in coeliac disease diagnosis in adults.

Accuracy of potential diagnostic indicators for coeliac disease: a systematic review protocol

INTRODUCTION

Coeliac disease (CD) is a systemic immune-mediated disorder triggered by gluten in genetically predisposed individuals. CD is diagnosed using a combination of serology tests and endoscopic biopsy of the small intestine. However, because of non-specific symptoms and heterogeneous clinical presentation, diagnosing CD is challenging. Early detection of CD through improved case-finding strategies can improve the response to a gluten-free diet, patients' quality of life and potentially reduce the risk of complications. However, there is a lack of consensus in which groups may benefit from active case-finding.

METHODS AND ANALYSIS

We will perform a systematic review to determine the accuracy of diagnostic indicators (such as symptoms and risk factors) for CD in adults and children, and thus can help identify patients who should be offered CD testing. MEDLINE, Embase, Cochrane Library and Web of Science will be searched from 1997 until 2020. Screening will be performed in duplicate. Data extraction will be performed by one and checked by a second reviewer. Disagreements will be resolved through discussion or referral to a third reviewer. We will produce a narrative summary of identified prediction models. Studies, where 2×2 data can be extracted or reconstructed, will be treated as diagnostic accuracy studies, that is, the diagnostic indicators are the index tests and CD serology and/or biopsy is the reference standard. For each diagnostic indicator, we will perform a bivariate random-effects meta-analysis of the sensitivity and specificity.

ETHICS AND DISSEMINATION

Results will be reported in peer-reviewed journals, academic and public presentations and social media. We will convene an implementation panel to advise on the optimum strategy for enhanced dissemination. We will discuss findings with Coeliac UK to help with dissemination to patients. Ethical approval is not applicable, as this is a systematic review and no research participants will be involved.

PROSPERO REGISTRATION NUMBER

CRD42020170766.

Update on celiac disease

PURPOSE OF REVIEW

The purpose of this review is to describe current updates in celiac disease.

RECENT FINDINGS

Recent developments in the understanding of the pathogenesis of celiac disease continue to emerge that may implicate the role of gluten exposure. Several studies have shown that the amount of gluten consumed by the infant may affect the age of onset of celiac disease in genetically predisposed individuals. New guidelines from the European Society of Paediatric Gastroenterology, Hepatology and Nutrition allow serology-based celiac diagnosis, omitting endoscopic biopsies, in children. Recent data and updated guidelines in adults no longer support biopsies in all patients who are genetically susceptible with celiac disease who have been identified by serology with clinical signs and symptoms of celiac disease. A new assay was identified in the immune response to epitopes of the tissue transglutaminase-deamidated gliadin peptide complex. In addition, a recent study shows that serum IL-2 elevations correlate with timing and severity of symptoms after gluten ingested in celiac disease patients. Measuring gluten immunogenic peptides (GIPs) in the stool of celiac patients may help monitor adherence to a gluten-free diet (GFD). Of importance, we should be aware that the quality of life is affected in celiac disease patients. During adolescence, the education on the importance of long-term follow-up with an adult gastroenterologist is associated with more successful rates of medical care transition for young adults with celiac disease. Latiglutenase, an orally administered mixture of two gluten-specific recombinant proteases that degrades gluten proteins into small physiologically irrelevant fragments, is currently in a phase 2 trial. Latiglutenase has shown to be safe and effective in reducing symptoms of celiac disease patients upon a GFD with improvement of quality of life. Lastly, a recent study describes a mouse model that is characteristic of celiac disease.

SUMMARY

Our knowledge of celiac disease continues to grow with increasing evidence of contributory factors to its pathogenesis. There is some evidence that the quantity ingested of gluten by the infant effects the age of onset of celiac disease in genetically susceptible patients. Changes have been made to the guidelines in the diagnosis of celiac disease proposed by new studies. Recent studies have shown the significant effects on quality of life for celiac patients. As improved laboratory methods continue to be developed, these tests can have utility in both diagnosis of celiac disease and monitoring adherence to the GFD. Current therapeutic trials offer promising nondietary treatment for celiac patients. The development of an animal model can provide a better understanding of the pathogenesis of celiac disease.

Celiac disease and bone health: is there a gap in the management of postmenopausal osteoporosis?

Malabsorption due to celiac disease (CD) may contribute to postmenopausal osteoporosis. This study aimed to survey participants with CD regarding their bone density, fractures, and bone-preserving medications; to compare tolerance of bone-preserving medications in participants with and without CD; and to review the evidence for CD screening and osteoporosis therapies in the setting of CD. We recruited 131 participants with CD and 102 participants without CD. Of those with CD, 87% were diagnosed in adulthood and 40% had no recognized gastrointestinal symptoms. In 21% CD was diagnosed after the diagnosis of osteoporosis and in 9% after a fracture. No difference was found in the tolerability of bone medications between participants with CD and those without. Review of the literature found that, although monitoring of bone health is recommended for patients with CD, screening for CD is not generally accepted for patients with osteoporosis, although studies of the prevalence of CD in osteoporosis had incomplete ascertainment methods. There is a lack of well-conducted studies and therefore insufficient data for the efficacy and tolerability of bone medication in CD. In conclusion, both CD and menopause lead to bone loss. Identifying CD in postmenopausal women should lead to modification of osteoporosis management.

Non-Biopsy Serology-Based Diagnosis of Celiac Disease in Adults Is Accurate with Different Commercial Kits and Pre-Test Probabilities

Non-biopsy diagnosis of celiac disease is possible in children with anti-transglutaminase 2 antibodies (TGA) > 10× the upper limit of normal (ULN) and positive anti-endomysial antibodies (EMA). Similar criteria have been suggested for adults, but evidence with different TGA assays is scarce. We compared the performance of four TGA tests in the diagnosis of celiac disease in cohorts with diverse pre-test probabilities. Serum samples from 836 adults with either clinical suspicion or family risk of celiac disease were tested with four commercial TGA assays, EmA and celiac disease-associated genetics. The diagnosis was set based on duodenal lesion or, in some cases, using special methods. 137 (57%) patients with clinical suspicion and 85 (14%) of those with family risk had celiac disease. Positive predictive value (PPV) for 10×ULN was 100% in each TGA test. The first non-diagnostic investigations were encountered with ULN 1.0×–5.1× in the clinical cohort and 1.3×–4.9× in the family cohort, respectively. Using the assays’ own cut-offs (1×ULN) the PPVs ranged 84–100%. Serology-based diagnosis of celiac disease was accurate in adults using different commercial kits and pre-test probabilities using 10×ULN. The results also suggest that the ULN threshold for biopsy-omitting approach could be lower.

Automated Analyzers Are Suited for Diagnosing Celiac Disease Without a Biopsy

OBJECTIVES

The European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) 2012 guidelines, enabled for the first time, a nonbiopsy approach in the diagnosis of celiac disease (CD). We aimed to prospectively assess 4 tissue-transglutaminase (tTg) IgA assays of 4 random-access analyzers and examine their accuracy in diagnosing CD without a biopsy.

METHODS

We enrolled 186 consecutive children referred to upper endoscopy and intestinal biopsy. One group included 109 patients with positive tTg that was referred for suspected CD. Another group included 77 patients with negative tTg referred because of other indications. All participants had a blood sample taken at the time of endoscopy. Samples were tested with 4 tTg IgA assays on automated analyzers and 1 Elisa kit. All intestinal biopsies were evaluated by a local pathologist, a central pathologist, and a CD expert blinded to each other. CD was diagnosed when full agreement was reached. Analytical performance of the assays included precision with controls and samples, lot to lot variation, and carryover.

RESULTS

In our cohort, all tested tTg IgA-automated assays showed sensitivities above 98% and specificities above 99%. ROC analysis demonstrated AUC (area under the curve) >0.99 for all 4 analyzers. The positive-predictive values (PPV) were all >0.99 and negative-predictive values (NPV) were >0.97. The Elisa kit had sensitivity of 95%, specificity of 96%, AUC of 0.96, PPV of 0.98 and NPV of 0.93.

CONCLUSION

CD can be accurately diagnosed without biopsy based on tTg IgA levels at least 10 times the ULN using the 4 high-volume random-access analyzers used in our study.

Progress in the serology-based diagnosis and management of adult celiac disease

Introduction: This article provides a comprehensive overview of the development and application of serological tests used routinely in clinical practice for the diagnosis and management of adult celiac disease.Areas covered: We summarize existing scientific literature related to anti-endomyseal, anti-tissue transglutaminase, and anti-deamidated gliadin peptide antibodies and detail the current and potential future applications of these tests in celiac disease.Expert commentary: Current serological tests in celiac disease have some of the best performance characteristics among disease-specific tests. However, in adult celiac disease, current diagnostic algorithms still rely on duodenal biopsies to confirm the diagnosis. A 'biopsy avoidance strategy' has been implemented in pediatric celiac disease. Future high-quality studies will help inform on whether this approach can be implemented into adult gastroenterology services. It is envisaged that the next 5 years will see an increasing reliance on serology in the diagnosis of adult celiac disease.

Celiac Disease

Gluten-related disorders, including celiac disease, wheat allergy, and nonceliac gluten sensitivity (NCGS), are increasingly reported worldwide. Celiac disease is caused by an immune-mediated reaction to ingested gluten in genetically susceptible persons. NCGS is largely a diagnosis of exclusion when other causes of symptoms have been ruled out. All patients with celiac disease should be referred to a registered dietitian nutritionist with expertise in celiac disease and a gastroenterologist who specializes in celiac disease and malabsorptive disorders, and they should remain on a strict gluten-free diet indefinitely. This article provides an overview of gluten- and wheat-related disorders.

LFRET, a novel rapid assay for anti-tissue transglutaminase antibody detection

The diagnosis of celiac disease (CD) is currently based on serology and intestinal biopsy, with detection of anti-tissue transglutaminase (tTG) IgA antibodies recommended as the first-line test. Emphasizing the increasing importance of serological testing, new guidelines and evidence suggest basing the diagnosis solely on serology without confirmatory biopsy. Enzyme immunoassays (EIAs) are the established approach for anti-tTG antibody detection, with the existing point-of-care (POC) tests lacking sensitivity and/or specificity. Improved POC methods could help reduce the underdiagnosis and diagnostic delay of CD. We have previously developed rapid homogenous immunoassays based on time-resolved Förster resonance energy transfer (TR-FRET), and demonstrated their suitability in serodiagnostics with hanta- and Zika virus infections as models. In this study, we set out to establish a protein L -based TR-FRET assay (LFRET) for the detection of anti-tTG antibodies. We studied 74 patients with biopsy-confirmed CD and 70 healthy controls, with 1) the new tTG-LFRET assay, and for reference 2) a well-established EIA and 3) an existing commercial POC test. IgG depletion was employed to differentiate between anti-tTG IgA and IgG positivity. The sensitivity and specificity of the first-generation tTG-LFRET POC assay in detection of CD were 87.8% and 94.3%, respectively, in line with those of the reference POC test. The sensitivity and specificity of EIA were 95.9% and 91.9%, respectively. This study demonstrates the applicability of LFRET to serological diagnosis of autoimmune diseases in general and of CD in particular.