AGA Clinical Practice Update on Diagnosis and Management of Cannabinoid Hyperemesis Syndrome: Commentary.

DESCRIPTION: The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update (CPU) is to review the available evidence and provide expert advice regarding diagnosis and management of cannabinoid hyperemesis syndrome. METHODS: This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. This expert commentary incorporates important as well as recently published studies in this field, and it reflects the experiences of the authors.

Patient and Community Health Global Burden in a World With More Celiac Disease.

Celiac disease is one of the most common life-long disorders worldwide, with a prevalence mostly ranging between 0.7% and 2.9% in the general population and a higher frequency in females and well-defined at-risk groups, such as relatives of affected individuals and patients with autoimmune comorbidities. Increasing clinical detection is facilitated by improving awareness, implementation of a case-finding approach, and serology availability for screening at-risk patients, among other factors. Nevertheless, due to huge clinical variability, many celiac disease cases still escape diagnosis in most countries, unless actively searched by proactive policies. The burden of celiac disease is increasing, as is the need for better longitudinal care. Pediatric screening of the general population could represent the road ahead for an efficient intervention of secondary prevention aimed to reduce the social and health burden of celiac disease. This review analyses the epidemiology of celiac disease continent by continent, discusses current strategies to improve the detection of celiac disease, and highlights challenges related to the burden of celiac disease globally.

Standardizing Randomized Controlled Trials in Celiac Disease: An International Multidisciplinary Appropriateness Study.

BACKGROUND & AIMS: There is a need to develop safe and effective pharmacologic options for the treatment of celiac disease (CeD); however, consensus on the appropriate design and configuration of randomized controlled trials (RCTs) in this population is lacking. METHODS: A 2-round modified Research and Development/University of California Los Angeles Appropriateness Method study was conducted. Eighteen gastroenterologists (adult and pediatric) and gastrointestinal pathologists voted on statements pertaining to the configuration of CeD RCTs, inclusion and exclusion criteria, gluten challenge, and trial outcomes. Two RCT designs were considered, representing the following distinct clinical scenarios for which pharmacotherapy may be used: trials incorporating a gluten challenge to simulate exposure; and trials evaluating reversal of histologic changes, despite attempted adherence to a gluten-free diet. Each statement was rated as appropriate, uncertain, or inappropriate, using a 9-point Likert scale. RESULTS: For trials evaluating prevention of relapse after gluten challenge, participants adherent to a gluten-free diet for 12 months or more with normal or near-normal-sized villi should be enrolled. Gluten challenge should be FODMAPS (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) free, and efficacy evaluated using histology with a secondary patient-reported outcome measure. For trials evaluating reversal of villus atrophy, the panel voted it appropriate to enroll participants with a baseline villus height to crypt depth ratio ≤2 and measure efficacy using a primary histologic end point. Guidance for measuring histologic, endoscopic, and patient-reported outcomes in adult and pediatric patients with CeD are provided, along with recommendations regarding the merits and limitations of different end points. CONCLUSIONS: We developed standardized recommendations for clinical trial design, eligibility criteria, outcome measures, gluten challenge, and disease evaluations for RCTs in patients with CeD.

Gluten-related Disorders From Bench to Bedside.

Celiac disease, non-celiac gluten sensitivity, and wheat allergy comprise 3 of the main conditions with wheat- and gluten-containing foods as the symptom trigger. Distinguishing between these entities can be daunting. In this review, we compare and contrast celiac disease, non-celiac gluten sensitivity, and wheat allergy to allow clinicians to determine which diagnosis fits their patient to facilitate high-quality management and longitudinal care.

Maternal, obstetrical, and neonatal outcomes in celiac disease.

OBJECTIVES: Some studies have suggested a link between celiac disease (CD) and adverse maternal, obstetrical, and neonatal outcomes. Using a large database, we evaluated the effect of CD on pregnancy outcomes. METHODS: We conducted a retrospective cohort study using the National Inpatient Sample (NIS) of all deliveries from 2015 to 2019 in the United States. Using ICD-10 codes, we identified pregnant patients who had CD and those who did not. A multivariate logistic regression was used to generate odds ratios (ORs) with 95% confidence intervals (CIs) for maternal, obstetrical, and neonatal outcomes. RESULTS: Of 12,039,222 deliveries between 2015 and 2019, there were 10,555 births in women with CD. Pregnant women with CD were more likely to be white and older compared to those without CD. Pregnant women with CD were significantly more likely to carry a diagnosis of gestational hypertension (OR 1.26; 95% CI 1.04-1.52), preeclampsia (1.28; 1.08-1.53), and severe preeclampsia (1.62; 1.25-2.09). They were less likely to have a full-term uncomplicated delivery (OR 0.11; 95% CI, 0.05-0.20), while being more likely to require device-assisted delivery (1.25; 1.04-1.50) and sustain 3rd or 4th degree vaginal lacerations (1.56; 1.21-2.02). Babies of pregnant women with CD were more likely to be small for gestational age (SGA) (OR 1.29; 95% CI 1.03-1.61). CONCLUSIONS: CD in pregnancy appears to be associated with increased adverse maternal, obstetrical, and neonatal outcomes. Clinicians should discuss these increased risks with CD patients who are planning to conceive.

A Dedicated Celiac Disease Program Improves Celiac Quality Care Metrics and Short-Term Outcomes in Real Life.

BACKGROUND AND AIMS: Dedicated multidisciplinary programs in gastroenterology are emerging with the goal to improve care. There is little information about the effects of a celiac disease program on disease-related quality care metrics and outcomes. We aimed to compare quality care metrics, symptom resolution, and serological response among patients diagnosed and treated in a celiac disease program with a standard of care cohort. METHODS: We performed a retrospective cohort study with adult celiac disease patients. We divided patients into two groups: celiac disease patients treated in our program and those treated by gastroenterologists not affiliated with the program (standard of care). We abstracted data from electronical medical records and compared frequency at which guideline-driven quality care metrics were obtained, assessed symptom resolution, and serological response based on IgA anti-tissue transglutaminase levels. RESULTS: We included 340 patients, 120 in the celiac disease program (89 women) and 220 (166 women) in the standard of care. Frequency of quality care metrics implementation in program patients was significantly greater for all variables (p < 0.0005). Diarrhea resolved in 38/46 (82.6%) in the CD program and 63/98 (64.2%) in the standard of care after starting a gluten-free diet (p = .025); bloating also resolved significantly more often in the former (26/34) than the latter (31/58; p = 0.03). Otherwise, there were no significant differences in resolution of clinical symptoms or serological response. CONCLUSION: A celiac disease program improves celiac-related quality care metrics and may improve outcomes such as diarrhea resolution compared to standard of care.

Increased Risk of Herpes Zoster Infection in Patients with Celiac Disease 50 Years Old and Older.

BACKGROUND: Celiac Disease (CD) is associated with increased susceptibility to certain bacterial and viral infections. Herpes zoster (HZ) is a viral infection that can be prevented by immunization. In the US, the vaccine is recommended for adults ≥ 50 or ≥ 19 with certain at-risk conditions, not including CD. AIMS: We aimed to determine if adult patients aged < 50 or ≥ 50 years with CD had a higher risk of developing HZ. METHODS: We designed a retrospective cohort study. CD was defined as patients with the ICD-10 code for CD and positive Celiac serology. Patients with negative serology and lacking CD ICD-10 codes served as controls. Patients who had HZ before CD diagnosis were excluded. We formed two sub-cohorts, those aged < 50 (cohort 1) and aged ≥ 50 years (cohort 2), and evaluated HZ infection at 10-year follow-up. To account for confounding variables, we performed 1:1 propensity score matching (PSM). RESULTS: Following PSM, cohort 1 had 6,826 CD patients, and cohort 2 had 5,337 CD patients and respective matched controls. After ten years of follow-up, in cohort 1, 62 CD patients developed HZ versus 57 controls, RR: 1.09 (CI: 0.76-1.56, p-value = 0.64). In cohort 2, 200 CD patients developed HZ versus 159 controls, RR: 1.2 (CI: 1.02-1.54, p-value = 0.03). CONCLUSION: There was no significant difference in the likelihood of getting HZ in CD patients < 50, although CD patients ≥ 50 had a modestly increased risk. Our findings do not support routine early vaccination for HZ in CD, and the vaccine should be offered at age 50.

AGA Clinical Practice Update on Management of Refractory Celiac Disease: Expert Review.

DESCRIPTION: The purpose of this expert review is to summarize the diagnosis and management of refractory celiac disease. It will review evaluation of patients with celiac disease who have persistent or recurrent symptoms, differential diagnosis, nutritional support, potential therapeutic options, and surveillance for complications of this condition. METHODS: This expert review was commissioned and approved by the American Gastroenterological Association (AGA) Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. These Best Practice Advice (BPA) statements were drawn from a review of the published literature and from expert opinion. Since systematic reviews were not performed, these BPA statements do not carry formal ratings of the quality of evidence or strength of the presented considerations. Best Practice Advice Statements BEST PRACTICE ADVICE 1: In patients believed to have celiac disease who have persistent or recurrent symptoms or signs, the initial diagnosis of celiac disease should be confirmed by review of prior diagnostic testing, including serologies, endoscopies, and histologic findings. BEST PRACTICE ADVICE 2: In patients with confirmed celiac disease with persistent or recurrent symptoms or signs (nonresponsive celiac disease), ongoing gluten ingestion should be excluded as a cause of these symptoms with serologic testing, dietitian review, and detection of immunogenic peptides in stool or urine. Esophagogastroduodenoscopy with small bowel biopsies should be performed to look for villous atrophy. If villous atrophy persists or the initial diagnosis of celiac disease was not confirmed, consider other causes of villous atrophy, including common variable immunodeficiency, autoimmune enteropathy, tropical sprue, and medication-induced enteropathy. BEST PRACTICE ADVICE 3: For patients with nonresponsive celiac disease, after exclusion of gluten ingestion, perform a systematic evaluation for other potential causes of symptoms, including functional bowel disorders, microscopic colitis, pancreatic insufficiency, inflammatory bowel disease, lactose or fructose intolerance, and small intestinal bacterial overgrowth. BEST PRACTICE ADVICE 4: Use flow cytometry, immunohistochemistry, and T-cell receptor rearrangement studies to distinguish between subtypes of refractory celiac disease and to exclude enteropathy-associated T-cell lymphoma. Type 1 refractory celiac disease is characterized by a normal intraepithelial lymphocyte population and type 2 is defined by the presence of an aberrant, clonal intraepithelial lymphocyte population. Consultation with an expert hematopathologist is necessary to interpret these studies. BEST PRACTICE ADVICE 5: Perform small bowel imaging with capsule endoscopy and computed tomography or magnetic resonance enterography to exclude enteropathy-associated T-cell lymphoma and ulcerative jejunoileitis at initial diagnosis of type 2 refractory celiac disease. BEST PRACTICE ADVICE 6: Complete a detailed nutritional assessment with investigation of micronutrient and macronutrient deficiencies in patients diagnosed with refractory celiac disease. Check albumin as an independent prognostic factor. BEST PRACTICE ADVICE 7: Correct deficiencies in macro- and micronutrients using oral supplements and/or enteral support. Consider parenteral nutrition for patients with severe malnutrition due to malabsorption. BEST PRACTICE ADVICE 8: Corticosteroids, most commonly open-capsule budesonide or, if unavailable, prednisone, are the medication of choice and should be used as first-line therapy in either type 1 or type 2 refractory celiac disease. BEST PRACTICE ADVICE 9: Patients with refractory celiac disease require regular follow-up by a multidisciplinary team, including gastroenterologists and dietitians, to assess clinical and histologic response to therapy. Identify local experts with expertise in celiac disease to assist with management. BEST PRACTICE ADVICE 10: Patients with refractory celiac disease without response to steroids may benefit from referral to a center with expertise for management or evaluation for inclusion in clinical trials.

Increased Risk of Hospitalization in Celiac Disease With COVID-19 Infection Is Mitigated by Vaccination.

BACKGROUND: We sought to describe clinical characteristics of celiac disease (CD) patients infected with coronavirus disease 2019 (COVID-19) and estimate hospitalization risk, intensive care unit (ICU) requirement, mortality, and thrombosis, and the impact of vaccination on these outcomes. METHODS: We performed a single-center, retrospective cohort study comparing biopsy-proven CD patients with a matched sample of non-CD (referent) patients diagnosed with COVID-19 between March 2020 and January 2022. Matching ensured 2 referent patients for every 1 CD patient by age, sex, ethnicity, and COVID-19 diagnosis date. We also adjusted for general and celiac-specific comorbidity. The primary outcome was hospitalization. Secondary outcomes included ICU requirement, mortality, and thrombosis. We also compared these outcomes between vaccinated and unvaccinated individuals. RESULTS: We included 330 patients: 110 with CD (mean age 47 years, 83% female) and 220 matched referents. Hospitalization occurred in 27 CD patients (24%) and 25 referent patients (11%) (hazard ratio, 2.10; 95% confidence interval, 1.21-3.65; P = .009). Vaccination was associated with significantly decreased risk of hospitalization (hazard ratio, 0.53; 95% confidence interval, 0.31-0.93; P = .026). Four unvaccinated CD patients and 2 unvaccinated referent patients required ICU. No mortality occurred among CD patients, and 2 referent patients died. No thrombosis occurred in either group. CONCLUSIONS: CD patients with COVID-19 have a higher risk of hospitalization compared with non-CD referents. This risk is mitigated by vaccination in CD patients as it is in non-CD referents. ICU requirement occurred only in unvaccinated CD patients, and no CD patient died. Vaccination against COVID-19 should be strongly recommended in patients with CD as it is for non-CD patients in the general population.

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.

Relationship between gluten availability and celiac disease prevalence: A geo-epidemiologic systematic review.

Celiac disease is a global disease requiring genetic susceptibility and gluten exposure to trigger immune-mediated enteropathy. The effect of the degree of gluten-containing grain availability on celiac disease prevalence is unknown. Our objective was to compare country-based gluten availability to celiac prevalence using a systematic literature review. We searched MEDLINE, Embase, Cochrane, and Scopus until May 2021. We included population-based serum screening with confirmatory testing (second serological study or small intestine biopsy) and excluded specific, high-risk, or referral populations. We determined country-specific gluten availability using the United Nations food balance for wheat, barley, and rye. Human leukocyte antigen (HLA) frequencies were obtained from allelefrequencies.net. The primary outcome was association between gluten-containing grain availability and celiac disease prevalence. Generalized linear mixed models method with Poisson's link was used for analysis. We identified 5641 articles and included 120 studies on 427 146 subjects from 41 countries. Celiac disease prevalence was 0-3.1%, median 0.75% (interquartile range 0.35, 1.22). Median wheat supply was 246 g/capita/day (interquartile range 214.8, 360.7). The risk ratio (RR) for wheat availability on celiac disease was 1.002 (95% confidence interval [CI]: 1.0001, 1.004, P = 0.036). A protective association was seen with barley, RR 0.973 (95% CI: 0.956, 0.99, P = 0.003), and rye, RR 0.989 (95% CI: 0.982, 0.997, P = 0.006). The RR for gross domestic product on celiac disease prevalence was 1.009 (95% CI: 1.005, 1.014, P < 0.001). The RR for HLA-DQ2 was 0.982 (95% CI: 0.979, 0.986, P < 0.001), and that for HLA-DQ8 was 0.957 (95% CI: 0.950, 0.964, P < 0.001). In this geo-epidemiologic study, gluten-containing grain availability showed mixed associations with celiac disease prevalence.

Self-Reported Gluten Intolerance Is Prevalent, but Not All Gluten-Containing Foods Are Equal.

BACKGROUND: Celiac disease prevalence approaches 1%; more suffer from non-celiac gluten sensitivity. AIMS: Our goal was to estimate the prevalence of gluten intolerance. METHODS: We invited US adults (18-80 years) via Amazon's mechanical Turk to complete an online survey. Gluten intolerance was defined as self-reported intolerance to wheat, barley, rye, flour, or pasta. Those with celiac disease were not excluded. RESULTS: We collected 2133 responses. Rate of gluten intolerance was 5.1% (95% CI 4.2-6.1%). Each food had different rates: wheat 4.8%, flour 1.2%, pasta 0.9%, barley 0.8%, and rye 0.8%. Among 108 adults reporting any gluten intolerance, 62.0% selected only wheat, 10.2% selected all gluten-containing grains excluding pasta and flour, and 5.6% selected all gluten-containing products. Overall intolerance to any food was 24.8% (95% CI 23.0-26.6%). Wheat was second only to lactose. CONCLUSIONS: Self-reported intolerance to wheat, but not all gluten-containing foods, is common. Findings may suggest poor knowledge of gluten-containing foods or that self-perceived non-celiac gluten sensitivity is prevalent.

Bi-directional Relationship Between Celiac Disease and Liver Chemistries: A Systematic Review and Meta-Analysis.

AIMS: Previous studies have reported conflicting results regarding prevalence of elevated LC (2-70%) in celiac disease (CD). This systematic review and meta-analysis assessed the prevalence of elevated LC at time of CD diagnosis and associated response to GFD. We also report the prevalence of CD in patients with unexplained elevation of LC. METHODS: Studies assessing LC (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) in CD patients were eligible. Studies with < 50 cases or in pediatric populations were excluded. RESULTS: In total, 20 studies assessing prevalence of elevated LC in 4,265 participants with newly diagnosed CD (mean age = 35.6 ± 6.5 years, 69.8% female) were included. Pooled prevalence of elevated LC was 18.7% (95% CI 13.8-24.8; I2 = 95%). Normalization of elevated LC was seen in 83.1% (95% CI 73.4-89.7; I2 = 79%, 11 studies) of patients after GFD. On meta-regression, age at CD diagnosis, gender, and Marsh grading were not associated with elevated LC. Among 979 participants (7 studies) with unexplained elevation of LC, pooled seroprevalence and biopsy-proven CD was 6.4% (95% CI 2.9-10.3, I2 = 71%) and 4.5% (95% CI 2.6-7.7, I2 = 67%), respectively. CONCLUSION: Elevated LC are seen in approximately one-fifth of patients at CD diagnosis with majority normalizing after GFD. Age, gender, and degree of intestinal damage are not predictive of elevated LC. In the appropriate clinical scenario, liver tests should be serially monitored in CD reserving workup for additional causes after a trial of GFD. Patients with unexplained elevation of liver tests should be screened for celiac disease.

Nomenclature and diagnosis of seronegative coeliac disease and chronic non-coeliac enteropathies in adults: the Paris consensus.

OBJECTIVE: Differential diagnosis of villous atrophy (VA) without coeliac antibodies in adults includes seronegative coeliac disease (CD) and chronic enteropathies unrelated to gluten, ie. non-coeliac enteropathies (NCEs). There is currently no international consensus on the nomenclature and diagnostic criteria for these enteropathies. In this work, a Delphi process was conducted to address this diagnostic and clinical uncertainty. DESIGN: An international task force of 13 gastroenterologists from six countries was recruited at the 16th International Coeliac Disease Symposium, Paris, 2019. Between September 2019 and July 2021, a Delphi process was conducted through mail surveys to reach a consensus on which conditions to consider in the differential diagnosis of VA with negative coeliac serology and the clinical diagnostic approaches required for these conditions. A 70% agreement threshold was adopted. RESULTS: Chronic enteropathies characterised by VA and negative coeliac serology can be attributed to two main clinical scenarios: forms of CD presenting with negative serology, which also include seronegative CD and CD associated with IgA deficiency, and NCEs, with the latter recognising different underlying aetiologies. A consensus was reached on the diagnostic criteria for NCEs assisting clinicians in differentiating NCEs from seronegative CD. Although in adults seronegative CD is the most common aetiology in patients with VA and negative serology, discriminating between seronegative CD and NCEs is key to avoid unnecessary lifelong gluten-free diet, treat disease-specific morbidity and contrast poor long-term outcomes. CONCLUSION: This paper describes the Paris consensus on the definitions and diagnostic criteria for seronegative CD and chronic NCEs in adults.

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.

AGA Clinical Practice Update on the Evaluation and Management of Seronegative Enteropathies: Expert Review.

DESCRIPTION: Our aim was to provide a consensus statement for the best approaches for diagnosis and management of patients with suspected enteropathy, but negative results from serologic tests for celiac disease (seronegative enteropathy). METHODS: We collected findings from published cohort, case-control, and cross-sectional studies of diagnosis and case series and descriptive studies of management of patients believed to have celiac disease or other enteropathies unrelated to gluten, but negative results from serologic tests. BEST PRACTICE ADVICE 1: Review histologic findings with experienced pathologists who specialize in gastroenterology. BEST PRACTICE ADVICE 2: Serologic tests are essential for an accurate diagnosis of celiac disease. For patients with suspected celiac disease but negative results from serologic tests, total IgA level should be measured; patients should also be tested for anti-tissue transglutaminase, IgA against deamidated gliadin peptide, and endomysial antibody (IgA). Patients with total IgA levels below the lower limit of detection and IgG against tissue transglutaminase or deamidated gliadin peptide, or endomysial antibody, should be considered to have celiac disease with selective IgA deficiency rather than seronegative celiac disease. BEST PRACTICE ADVICE 3: Patients' diets should be carefully reviewed and duodenal biopsies should be collected and analyzed at the time of serologic testing to determine exposure to gluten and accuracy of test results. BEST PRACTICE ADVICE 4: Thorough medication histories should be collected from patients, with attention to angiotensin II receptor blockers, such as olmesartan, along with travel histories to identify potential etiologies of villous atrophy. This will guide additional testing. BEST PRACTICE ADVICE 5: Patients should be analyzed for disease-associated variants in human leukocyte antigen genes; results must be carefully interpreted. Negative results can be used to rule out celiac disease in seronegative patients. BEST PRACTICE ADVICE 6: Patients with suspected celiac disease who are seronegative but have villous atrophy and genetic risk factors for celiac disease must undergo endoscopic evaluation after 1-3 years on a gluten-free diet to evaluate improvements in villous atrophy. A diagnosis of seronegative celiac disease can then be confirmed based on clinical and histologic markers of improvement on the gluten-free diet. BEST PRACTICE ADVICE 7: Seronegative patients with an identified cause for enteropathy should be treated accordingly; a follow-up biopsy might or might not be necessary. BEST PRACTICE ADVICE 8: Patients with persistent signs and symptoms who do not respond to a gluten-free diet, and for whom no etiology of enteropathy is ultimately identified, should be treated with budesonide. CONCLUSIONS: These best practice guidelines will aid in diagnosis and management of patients with suspected celiac disease, but negative results from serologic tests.

AGA Clinical Practice Update on Diagnosis and Management of Immune Checkpoint Inhibitor Colitis and Hepatitis: Expert Review.

BACKGROUND & AIMS: Immune checkpoint inhibitors (ICIs) have transformed the treatment landscape for oncology, leading to durable remissions in a subset of patients, but also a broad range of potentially life-threatening inflammatory toxicities, many of which involve the gastrointestinal (GI) tract and liver. The purpose of this expert review was to update gastroenterologists on the gastrointestinal and hepatic toxicities of ICIs and provide best practice advice on their diagnosis and management. METHODS: The evidence reviewed in this work combines the expert clinical opinion of the authors with a comprehensive search of several English-language databases and a manual review of relevant publications.

Community-Based Study of Celiac Disease Autoimmunity Progression in Adults.

BACKGROUND & AIMS: Celiac disease can develop at any age, but outcomes of adults with positive results from serologic tests for tissue transglutaminase antibodies (tTGA) without endoscopic determination of celiac disease (called celiac autoimmunity) have not been thoroughly evaluated. We investigated the proportion of adults with celiac autoimmunity at a community medical center and their progression to celiac disease. METHODS: We analyzed waste blood samples from a community clinic from 15,551 adults for tTGA and, if titer results were above 2 U/mL, for endomysial antibody. The blood samples had been collected at 2 time points (median interval, 8.8 years) from 2006 through 2017. We collected data from the clinic on diagnoses of celiac disease based on duodenal biopsy analysis. RESULTS: Of the serum samples collected at the first time point, 15,398 had negative results for tTGA, and 153 had positive results for tTGA (>4 U/mL). Based on medical records, 6 individuals received a diagnosis of celiac disease, for a cumulative incidence of celiac disease diagnosis of 0.06% (95% confidence interval, 0.01-0.11). Forty-nine (0.32%) individuals with a negative result from the first serologic test for tTGA had a positive result from the second test. Among the 153 adults who were tTGA positive at the first time point, 31 (20%) had a subsequent diagnosis of celiac disease, 81 (53%) remained positive for tTGA without a clinical diagnosis of celiac disease, and 41 (27%) had negative test results for tTGA at the second time point. Higher initial tTGA titers, female sex, and a history of hypothyroidism and autoimmune disease were associated with increased risks of subsequent diagnosis of celiac disease. Interestingly, adults whose first blood sample had a positive test result but second blood sample had a negative result for tTGA were older, had lower-than-average initial tTGA titer results, and had a higher mean body mass index than adults whose blood samples were positive for tTGA at both time points and adults later diagnosed with celiac disease. CONCLUSIONS: In an analysis of serum samples collected from a community clinic an average of 8.8 years apart, we found that fewer than 1% of adults with negative results from an initial test for tTGA have a positive result on a second test. Of adults with positive results from the test for tTGA, only 20% are later diagnosed with celiac disease; the remaining individuals maintain persistent increases in tTGA without diagnoses of celiac disease or have negative results from second tests.

Estimating the Impact of Verification Bias on Celiac Disease Testing.

GOAL: The goal of this study was to estimate the impact of verification bias on the diagnostic accuracy of immunoglobulin A tissue transglutaminase (IgA tTG) in detecting celiac disease as reported by an authoritative meta-analysis, the 2016 Comparative Effectiveness Review (CER). BACKGROUND: Verification bias is introduced to diagnostic accuracy studies when screening test results impact the decision to verify disease status. MATERIALS AND METHODS: We adjusted the sensitivity and specificity of IgA tTG reported by the 2016 CER with the proportion of IgA tTG positive and negative individuals who are referred for confirmatory small bowel biopsy. We performed a systematic review from January 1, 2007, to July 19, 2017, to determine these referral rates. RESULTS: The systematic review identified 793 articles of which 9 met inclusion criteria (n=36,477). Overall, 3.6% [95% confidence interval (CI): 1.1%-10.9%] of IgA tTG negative and 79.2.2% (95% CI: 65.0%-88.7%) of IgA tTG positive individuals were referred for biopsy. Adjusting for these referral rates the 2016 CER reported sensitivity of IgA tTG dropped from 92.6% (95% CI: 90.2%-94.5%) to 57.1% (95% CI: 35.4%-76.4%) and the specificity increased from 97.6% (95% CI: 96.3%-98.5%) to 99.6% (95% CI: 98.4%-99.9%). CONCLUSIONS: The CER may have largely overestimated the sensitivity of IgA tTG due to a failure to account for verification bias. These findings suggest caution in the interpretation of a negative IgA tTG to rule out celiac disease in clinical practice. More broadly, they highlight the impact of verification bias on diagnostic accuracy estimates and suggest that studies at risk for this bias be excluded from systematic reviews.

The Risk of Acute and Chronic Pancreatitis in Celiac Disease.

BACKGROUND AND AIMS: Celiac disease (CD) is a chronic immune-mediated enteropathy that is precipitated by dietary gluten in genetically predisposed individuals. A few studies reported a higher incidence of pancreatitis in the CD population. Using a large US database, we sought to describe the epidemiology, risk, and outcomes of acute pancreatitis (AP) and chronic pancreatitis (CP) in CD patients. METHODS: We queried a multiple health system data analytics and research platform (Explorys Inc, Cleveland, OH, USA). A cohort of patients with a diagnosis of CD was identified. Subsequently, individuals who developed a new diagnosis of AP and CP after at least 30 days of being diagnosed with CD were identified. A multivariate regression model was performed to adjust for multiple confounding factors. RESULTS: Of the 72,965,940 individuals in the database, 133,400 (0.18%), 362,050 (0.50%), and 95,190 (0.13%) had CD, AP, and CP, respectively. New diagnosis of AP and CP after at least 30 days of CD diagnosis was 1.06%, 0.52%, respectively, compared to non-CD patients with 0.49% for AP and 0.13% for CP, P < .0001. In multivariate regression analysis, patients with CD were at higher risk of developing AP [OR 2.66; 95% CI 2.55-2.77] and CP [OR 2.18; 95% CI 2.04-2.34]. Idiopathic AP was the most common etiology among CD patients [OR 1.54; 95% CI 1.34-1.77]. CONCLUSIONS: In this largest US population database and after adjusting for several confounders, patients with CD were at increased risk of developing AP and CP. Celiac disease patients had worse outcomes and higher medical burden compared to non-CD patients. Recurrent abdominal pain that suggests pancreatic etiology, idiopathic pancreatitis, or elevation of pancreatic enzymes should warrant investigation for CD as a potential cause of pancreatic disease.