Fecal Gluten Peptides Reveal Limitations of Serological Tests and Food Questionnaires for Monitoring Gluten-Free Diet in Celiac Disease Patients

Objectives: Treatment for celiac disease (CD) is a lifelong strict gluten-free diet (GFD). Patients should be followed-up with dietary interviews and serology as CD markers to ensure adherence to the diet. However, none of these methods offer an accurate measure of dietary compliance. Our aim was to evaluate the measurement of gluten immunogenic peptides (GIP) in stools as a marker of GFD adherence in CD patients and compare it with traditional methods of GFD monitoring. Methods: We performed a prospective, nonrandomized, multicenter study including 188 CD patients on GFD and 84 healthy controls. Subjects were given a dietary questionnaire and fecal GIP quantified by enzyme-linked immunosorbent assay (ELISA). Serological anti-tissue transglutaminase (anti-tTG) IgA and anti-deamidated gliadin peptide (anti-DGP) IgA antibodies were measured simultaneously. Results: Of the 188 celiac patients, 56 (29.8%) had detectable GIP levels in stools. There was significant association between age and GIP in stools that revealed increasing dietary transgressions with advancing age (39.2% in subjects ≥13 years old) and with gender in certain age groups (60% in men ≥13 years old). No association was found between fecal GIP and dietary questionnaire or anti-tTG antibodies. However, association was detected between GIP and anti-DGP antibodies, although 46 of the 53 GIP stool-positive patients were negative for anti-DGP. Conclusions: Detection of gluten peptides in stools reveals limitations of traditional methods for monitoring GFD in celiac patients. The GIP ELISA enables direct and quantitative assessment of gluten exposure early after ingestion and could aid in the diagnosis and clinical management of nonresponsive CD and refractory CD. Trial registration number NCT02711397

Marrow aplasia during high dose mebendazole treatment

A patient with chronic liver disease was treated with large doses of mebendazole for a hepatic hydatid cyst. Eighteen days after beginning treatment he developed marrow aplasia which reverted to normal after the drug was stopped. This is the sixth patient described as developing marrow aplasia when treated with large doses of mebendazole. We suggest that the aplasia is related to the dose of the drug, and that the patient's chronic liver disease was an important factor in its genesis. Patients treated with large doses of mebendazole should have their blood counts monitored during treatment

Marrow aplasia during high dose mebendazole treatment

A patient with chronic liver disease was treated with large doses of mebendazole for a hepatic hydatid cyst. Eighteen days after beginning treatment he developed marrow aplasia which reverted to normal after the drug was stopped. This is the sixth patient described as developing marrow aplasia when treated with large doses of mebendazole. We suggest that the aplasia is related to the dose of the drug, and that the patient's chronic liver disease was an important factor in its genesis. Patients treated with large doses of mebendazole should have their blood counts monitored during treatment

Colonic bacterial diversity and dysbiosis in active microscopic colitis as compared to chronic diarrhoea and healthy controls: effect of polyethylene glycol after bowel lavage for colonoscopy

Faecal microbiome; Microscopic colitis; Polyethylene glycolMicrobioma fecal; Colitis microscópica; PolietilenglicolMicrobioma fecal; Colitis microscòpica; PolietilenglicolBackground Most microbiota studies in microscopic colitis patients are performed after diagnostic colonoscopy without considering the potential effect of colonic lavage. Patients may achieve clinical remission after colonoscopy and it is unknown whether lavage-induced changes play a role. Aim To assess the effect of polyethylene glycol (PEG) colonic lavage on clinical remission rate, microbial diversity, microbial dysbiosis index and specific microbial changes in patients with active microscopic colitis as compared to other diarrhoeal diseases and healthy controls. Methods Fifty-five consecutive patients presenting chronic watery diarrhoea and 12 healthy controls were included. Faecal samples were collected three days before and 30 days after PEG in patients and controls for microbiome analysis. Results Clinical remission was observed in 53% of microscopic colitis patients, and in 32% of non-microscopic colitis patients (p = 0.16). Considering patients with persisting diarrhoea after colonoscopy, 71% of non-microscopic colitis patients had bile acid diarrhoea. Baseline Shannon Index was lower in diarrhoea groups than in healthy controls (p = 0.0025); there were no differences between microscopic colitis, bile-acid diarrhoea and functional diarrhoea. The microbial dysbiosis index was significantly higher in microscopic colitis than in bile acid diarrhoea plus functional diarrhoea (p = 0.0095), but no bacterial species showed a significantly different relative abundance among the diarrheal groups. Conclusions Dysbiosis is a feature in active microscopic colitis, but loss of microbial diversity was similar in all diarrheal groups, suggesting that faecal microbial changes are not due to microscopic colitis itself but associated with stool form. A considerable number of microscopic colitis patients achieved clinical remission after colonoscopy, but we were unable to demonstrate related PEG-induced changes in faecal microbiome

A Scoring System for Identifying Patients Likely to Be Diagnosed with Low-Grade Coeliac Enteropathy

Background & aims: Determining whether patients with lymphocytic enteritis (LE) have coeliac disease is a challenge. We analysed the variables associated with a low-grade coeliac enteropathy diagnosis in patients with suspected coeliac disease but without villous atrophy, and developed a scoring system to identify them. Methods: We collected data from 2010 through to 2016 on patients with lymphocytic enteritis and persistent symptoms compatible with the clinical spectrum of coeliac disease. One hundred and four patients starting on a gluten-free diet (GFD) were included. Duodenal biopsies were collected before the GFD and analysed for numbers of CD3+ T-cell receptor gamma delta+ (TCRγδ+), and CD3- intraepithelial lymphocytes. We performed a logistic regression analysis to identify factors associated with a low-grade coeliac enteropathy diagnosis. Results: Sixty-two patients achieved clinical remission after the GFD. Fifty of these 62 patients were diagnosed with low-grade coeliac enteropathy. Multivariate analysis identified the presence of >25% intraepithelial lymphocytosis, HLA-DQ2.5, positive serology, and increased numbers of TCRγδ+ cells with a low-grade coeliac enteropathy diagnosis. We developed a scoring system that identified patients with an area under the ROC curve (AUC) of 0.91. Scores of >10 had 86% sensitivity and 85% specificity. Conclusion: We developed a scoring system that identifies patients likely to be diagnosed with low-grade coeliac enteropathy with an AUC value of 0.91

Cereal Proteins: Immunostimulatory and Toxic Peptides

Storage proteins from wheat kernels are the base of a wide variety of homemade and industrial food products. Nonetheless, for a group of individuals (celiac disease (CD) patients), these proteins are toxic. Gliadins and glutenins from wheat, as well as their counterparts in barley and rye, also called prolamins, are evolutionary related, and present a high degree of homology. Polyclonal and monoclonal antibodies raised against prolamins have been a very useful tool to characterise structural and conformational features of prolamins, and particularly, for gluten analysis based on immunochemical techniques. Complete adherence to a gluten-free diet is required to recover the normal histology of the small intestine in CD patients. To this end, the use of certified gluten-free products is mandatory. Aqueous solvents such as 60-70% ethanol, have been used for extraction of prolamins from flours and food. This method is not selective and, therefore, results in complex mixtures of proteins which together with their low solubility in aqueous solutions, high degree of homology, and consequently crossreactivity, produce some drawbacks in gluten analysis by immunoassays. Prolamins drive an exacerbated immune response in intestinal mucosa of CD patients. T lymphocytes are a central piece in CD pathogenesis. However, new insights in the knowledge of innate immunity point out to some gliadin peptides which can also produce structural changes in the intestine as well as inflammatory reactions.Instituto de Estudios Inmunológicos y Fisiopatológico

Femtosecond XUV–IR induced photodynamics in the methyl iodide cation

The time-resolved photodynamics of the methyl iodide cation (CH3I+) are investigated by means of femtosecond XUV-IR pump-probe spectroscopy. A time-delay-compensated XUV monochromator is employed to isolate a specific harmonic, the 9th harmonic of the fundamental 800 nm (13.95 eV, 88.89 nm), which is used as a pump pulse to prepare the cation in several electronic states. A time-delayed IR probe pulse is used to probe the dissociative dynamics on the first excited state potential energy surface. Photoelectrons and photofragment ions - and I+ - are detected by velocity map imaging. The experimental results are complemented with high level ab initio calculations for the potential energy curves of the electronic states of CH3I+ as well as with full dimension on-the-fly trajectory calculations on the first electronically excited state, considering the presence of the IR pulse. The and I+ pump-probe transients reflect the role of the IR pulse in controlling the photodynamics of CH3I+ in the state, mainly through the coupling to the ground state and to the excited state manifold. Oscillatory features are observed and attributed to a vibrational wave packet prepared in the state. The IR probe pulse induces a coupling between electronic states leading to a slow depletion of fragments after the cation is transferred to the ground states and an enhancement of I+ fragments by absorption of IR photons yielding dissociative photoionization. © 2021 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft

Femtosecond XUV–IR induced photodynamics in the methyl iodide cation

The time-resolved photodynamics of the methyl iodide cation (CH3I+) are investigated by means of femtosecond XUV–IR pump–probe spectroscopy. A time-delay-compensated XUV monochromator is employed to isolate a specific harmonic, the 9th harmonic of the fundamental 800 nm (13.95 eV, 88.89 nm), which is used as a pump pulse to prepare the cation in several electronic states. A time-delayed IR probe pulse is used to probe the dissociative dynamics on the first excited $\tilde {A}\enspace {}^{2}\mathrm{A}_{1}$ state potential energy surface. Photoelectrons and photofragment ions—${\mathrm{C}\mathrm{H}}_{3}^{+}$ and I+—are detected by velocity map imaging. The experimental results are complemented with high level ab initio calculations for the potential energy curves of the electronic states of CH3I+ as well as with full dimension on-the-fly trajectory calculations on the first electronically excited state $\tilde {A}\enspace {}^{2}\mathrm{A}_{1}$, considering the presence of the IR pulse. The ${\mathrm{C}\mathrm{H}}_{3}^{+}$ and I+ pump–probe transients reflect the role of the IR pulse in controlling the photodynamics of CH3I+ in the $\tilde {A}\enspace {}^{2}\mathrm{A}_{1}$ state, mainly through the coupling to the ground state $\tilde {X}\enspace {}^{2}\mathrm{E}_{3/2,1/2}$ and to the excited $\tilde {B}\enspace {}^{2}\mathrm{E}$ state manifold. Oscillatory features are observed and attributed to a vibrational wave packet prepared in the $\tilde {A}\enspace {}^{2}\mathrm{A}_{1}$ state. The IR probe pulse induces a coupling between electronic states leading to a slow depletion of ${\mathrm{C}\mathrm{H}}_{3}^{+}$ fragments after the cation is transferred to the ground $\tilde {X}\enspace {}^{2}\mathrm{E}_{3/2,1/2}$ states and an enhancement of I+ fragments by absorption of IR photons yielding dissociative photoionization

Intestinal intraepithelial lymphocyte cytometric pattern is more accurate than subepithelial deposits of anti-tissue transglutaminase IgA for the diagnosis of celiac disease in lymphocytic enteritis

Background & Aims: An increase in CD3+TCRγδ+ and a decrease in CD3− intraepithelial lymphocytes (IEL) is a characteristic flow cytometric pattern of celiac disease (CD) with atrophy. The aim was to evaluate the usefulness of both CD IEL cytometric pattern and anti-TG2 IgA subepithelial deposit analysis (CD IF pattern) for diagnosing lymphocytic enteritis due to CD. Methods: Two-hundred and five patients (144 females) who underwent duodenal biopsy for clinical suspicion of CD and positive celiac genetics were prospectively included. Fifty had villous atrophy, 70 lymphocytic enteritis, and 85 normal histology. Eight patients with non-celiac atrophy and 15 with lymphocytic enteritis secondary to Helicobacter pylori acted as control group. Duodenal biopsies were obtained to assess both CD IEL flow cytometric (complete or incomplete) and IF patterns. Results: Sensitivity of IF, and complete and incomplete cytometric patterns for CD diagnosis in patients with positive serology (Marsh 1+3) was 92%, 85 and 97% respectively, but only the complete cytometric pattern had 100% specificity. Twelve seropositive and 8 seronegative Marsh 1 patients had a CD diagnosis at inclusion or after gluten free-diet, respectively. CD cytometric pattern showed a better diagnostic performance than both IF pattern and serology for CD diagnosis in lymphocytic enteritis at baseline (95% vs 60% vs 60%, p = 0.039). Conclusions: Analysis of the IEL flow cytometric pattern is a fast, accurate method for identifying CD in the initial diagnostic biopsy of patients presenting with lymphocytic enteritis, even in seronegative patients, and seems to be better than anti-TG2 intestinal deposits

Prediction of advanced colonic neoplasm in symptomatic patients: a scoring system to prioritize colonoscopy (COLONOFIT study).

Background: Fast-track colonoscopy to detect patients with colorectal cancer based on high-risk symptoms is associated with low sensitivity and specificity. The aim was to derive a predictive score of advanced colonic neoplasia in symptomatic patients in fast-track programs. Methods: All patients referred for fast-track colonoscopy were evaluated. Faecal immunological haemoglobin test (3 samples; positive> 4 μg Hb/g), and a survey to register clinical variables of interest were performed. Colorectal cancer and advanced adenoma were considered as advanced colonic neoplasia. A sample size of 600 and 500 individuals were calculated for each phase 1 and phase 2 of the study, respectively (Phase 1, derivation and Phase 2, validation cohort). A Bayesian logistic regression analysis was used to derive a predictive score. Results: 1495 patients were included. Age (OR, 21), maximum faecal-Hb value (OR, 2.3), and number of positive samples (OR, 28) presented the highest ORs predictive of advanced colonic neoplasia. The additional significant predictive variables adjusted for age and faecal-Hb variables in Phase 1 were previous colonoscopy (last 5 years) and smoking (no, ex/active). With these variables a predictive score of advanced colonic neoplasia was derived. Applied to Phase 2, patients with a Score > 20 had an advanced colonic neoplasia probability of 66% (colorectal cancer, 32%), while those with a Score ≤ 10, a probability of 10% (colorectal cancer, 1%). Prioritizing patients with Score > 10, 49.4% of patients would be referred for fast-track colonoscopy, diagnosing 98.3% of colorectal cancers and 77% of advanced adenomas. Conclusions: A scoring system was derived and validated to prioritize fast-track colonoscopies according to risk, which was efficient, simple, and robust