"The crackers challenge": A reassuring low-dose gluten challenge in adults on gluten-free diet without proper diagnosis of coeliac disease.

BACKGROUND: Gluten-free diet (GFD) is the one therapy in coeliac disease (CeD). Unfortunately, some patients adopt GFD before the diagnostic work-up. The guidelines suggest a 14-day gluten intake > 3 gr to get CeD diagnosis, although many subjects refuse this approach. Other evidence showed that the intake of 50 mg/day of gluten for 3 months could be useful for CeD diagnosis. AIMS: We performed a dietary study, administering a low dose of gluten in form of "crackers" (about 60-120 mg of gluten/day) for 3 months, to get a final diagnosis of CeD in subjects already on GFD. METHODS: We enrolled adult patients with a suspicion of CeD on self-prescribed GFD. All subjects performed the crackers challenge for 3 months. At the end, all patients were analysed for CeD serology and if positive underwent endoscopy/histology. Also, we recorded the grade of satisfaction for the gluten challenge and the onset of adverse events. RESULTS: We enrolled 120 patients. All patients concluded the challenge without relevant adverse events. Serological positivity was detected in 54 patients (45%). Histology showed atrophy in 87% and Marsh 1-2 grade in 13% of patients. Ninety-nine patients (83%) were satisfied by this challenge. CONCLUSIONS: The "crackers challenge" is a useful and safe diagnostic approach in people on self-administered GFD.

"Per ELISA": Time to adopt anti-transglutaminase/deamidated gliadin peptide diagnostic combination in coeliac disease of adults?

BACKGROUND: Anti-endomysial antibodies (EMA) and anti-tissue transglutaminases (a-tTg) play a pivotal role in coeliac disease (CD) diagnosis. Deamidated anti-gliadin peptides (DGP) were added to the CD diagnostic workup. AIMS: We aimed to compare the diagnostic accuracies of ELISA-based (a-tTg/DGP) and immunofluorescence-ELISA-based strategies (EMA/a-tTg) for CD diagnosis. METHODS: From November 2020 to November 2022, we undertook an observational prospective study including consecutive adult patients with suspected CD. All subjects were tested for EMA, a-tTg and DGP IgA. An ROC curve was plotted to establish the best specificity cut-off of a-tTg and DGP levels, which would predict the presence of Marsh≥2 and Marsh=3. The diagnostic accuracies of a-tTg/DG and EMA/a-tTg were compared. RESULTS: The study included 275 CD patients. Histology showed Marsh=1 in 9.9%, Marsh=2 in 4.5%, and Marsh=3 in 85.6.%. The best cut-off value of a-tTg for predicting Marsh≥2 was 42 U/mL, while the best cut-off for predicting atrophy was 68.4 U/mL. The best cut-off value of DGP for predicting Marsh≥2 was 56 U/mL, while the best cut-off for predicting atrophy was 78 U/mL. A-tTg/EMA showed 97% sensitivity and 100% specificity, whereas a-tTg/DGP showed 94% sensitivity and 100% specificity. CONCLUSION: A-tTg/DGP is accurate for CD diagnosis and could reduce costs and operator-dependency of EMA. DGP, together with a-tTg, could replace EMA in CD diagnosis.

David Against Goliath: Direct Comparison of Handheld Bowel Sonography and Magnetic Resonance Enterography for Diagnosis of Crohn's Disease.

BACKGROUND: Diagnosis of Crohn's disease (CD) requires ileo-colonoscopy (IC) and cross-sectional evaluation. Recently, "echoscopy" has been used effectively in several settings, although data about its use for CD diagnosis are still limited. Our aim was to evaluate the diagnostic accuracy of handheld bowel sonography (HHBS) in comparison with magnetic resonance enterography (MRE) for CD diagnosis. METHODS: From September 2019 to June 2021, we prospectively recruited consecutive subjects attending our third level IBD Unit for suspected CD. Patients underwent IC, HHBS, and MRE in random order with operators blinded about the result of the other procedures. Bivariate correlation between MRE and HHBS was calculated by Spearman coefficient (r). To test the consistency between MRE and HHBS for CD location and complications, the Cohen's k measure was applied. RESULTS: Crohn's disease diagnosis was made in 48 out of 85 subjects (56%). Sensitivity, specificity, positive predictive values, and negative predictive values for CD diagnosis were 87.50%, 91.89%, 93.33%, and 85% for HHBS; and 91.67%, 94.59%, 95.65%, and 89.74% for MRE, without significant differences in terms of diagnostic accuracy (89.41% for HHBS vs 92.94% for MRE, P = NS). Magnetic resonance enterography was superior to HHBS in defining CD extension (r = 0.67; P < .01) with a better diagnostic performance than HHBS for detecting location (k = 0.81; P < .01), strictures (k = 0.75; P < .01), abscesses (k = 0.68; P < .01), and fistulas (k = 0.65; P < .01). CONCLUSION: Handheld bowel sonography and MRE are 2 accurate and noninvasive procedures for diagnosis of CD, although MRE is more sensitive in defining extension, location, and complications. Handheld bowel sonography could be used as effective ambulatory (or out-of-office) screening tool for identifying patients to refer for MRE examination due to high probability of CD diagnosis.

Exploring the concept of deep remission in Crohn's disease: correlation between transmural healing and biomarkers.

Background: While mucosal healing (MH) and transmural healing (TH) predict relevant clinical outcomes in Crohn's disease (CD), little is known about the real significance and clinical impact of deep remission (DR). Objectives: To better explore the concept of DR, toward a direct correlation between MH, TH, and biomarkers. Design: Real-world observational longitudinal study to evaluate the rate of clinical remission (CR), MH and TH, and the fecal calprotectin (FC)/C-reactive protein (CRP) levels in all consecutive CD patients on biologics. Methods: A receiver operating characteristic (ROC) curve was constructed to define the best FC and CRP cut-offs associated with MH and TH. Finally, patients achieving CR, MH, and TH, in association with the target FC/CRP values, were considered in DR. Results: Among 118 CD patients, CR, MH, and TH were achieved in 62.7, 44.1, and 32.2%, respectively. After 2 years, the mean FC levels decreased from 494 ± 15.4 µg/g to 260 ± 354.9 µg/g (p < 0.01). Using the ROC curve analysis, an FC cut-off value of 94 µg/g was associated with both MH [sensitivity: 94.2%, specificity: 84.8%, positive predictive value (PPV): 83.05%, negative predictive value (NPV): 94.92%, area under the curve (AUC): 0.95] and TH (sensitivity: 92.1%, specificity: 70%, PPV: 64.4%, NPV: 94.9%, AUC: 0.88). CRP < 5 mg/L was associated with both MH (sensitivity: 96.1%, specificity: 62.1%, PPV: 66.7%, NPV: 95.35%, AUC: 0.85) and TH (sensitivity: 97.4%, specificity: 52.5%, PPV: 52%, NPV: 95.35%, AUC: 0.78). When considering CD patients with concomitant CR, MH, and TH associated with an FC < 94 µg/g and CRP < 5 mg/L, this association was found identified in 33 patients (27.9%). Conclusion: An FC < 94 µg/g and a normal CRP are associated with CR, MH, and TH and could be included in the definition of DR in association. So by definition, DR could be achieved in approximately 30% of CD patients during maintenance treatment with biologics.

Ultrasonography-Based Management of Sclerosing Mesenteritis: From Diagnosis to Follow-Up.

Sclerosing mesenteritis (SM) is an idiopathic disorder affecting mesentery, characterized by fat necrosis, chronic inflammation and fibrosis. The clinical presentation varies from asymptomatic cases to acute abdomen. The diagnosis is suggested by imaging but can be definitely established only by biopsies. In this paper, we discuss ultrasonography-based management of SM.

Metabolic-associated fatty liver disease (MAFLD) in coeliac disease.

BACKGROUND AND AIMS: Coeliac disease (CD) is considered a high-risk condition for developing non-alcoholic fatty liver disease (NAFLD) and other related metabolic disorders, particularly after commencing gluten-free diet (GFD). Recently, a new concept of metabolic-associated fatty liver disease (MAFLD) has been proposed to overcome the limitations of NAFLD definition. This study aimed at exploring the prevalence of NAFLD and MAFLD in CD patients at the time of CD diagnosis and after 2 years of GFD. Furthermore, we evaluated the role of PNPLA3 rs738409 in the development of NAFLD and MAFLD in the same population. METHODS: We retrospectively enrolled all newly diagnosed CD patients who underwent clinical, laboratory and ultrasonography investigations both at diagnosis and after 2 years of follow-up. Moreover, a PNPLA3 rs738409 genotyping assay was performed. RESULTS: Of 221 newly diagnosed CD patients, 65 (29.4%) presented NAFLD at CD diagnosis, while 32 (14.5%) met the criteria for MAFLD (k = 0.57). There were no significant differences between NAFLD and MAFLD, except for the higher rate of insulin resistance (IR) of MAFLD patients (75% vs 33.8%, P < .001). At 2 years of follow-up, 46.6% of patients developed NAFLD while 32.6% had MAFLD (k = 0.71). MAFLD subjects had higher transaminases (P = .03), LDL-cholesterol (P = .04), BMI and waist circumference and higher IR than NAFLD patients. MAFLD patients showed higher non-invasive liver fibrosis scores than NAFLD subjects (APRI = 1.43 ± 0.56 vs 0.91 ± 0.62, P < .001; NFS=-1.72 ± 1.31 vs -2.18 ± 1.41, P = .03; FIB-4 = 1.27 ± 0.77 vs 1.04 ± 0.74, P = .04). About PNPLA3 polymorphisms, at 2 years follow-up, NAFLD subjects presented a higher rate of heterozygosis (40.8%) and homozygosis (18.4%) polymorphisms than non-NAFLD (26.3% and 7.6%, respectively, P = .03 and 0.02), while no correlation between PNPLA3 polymorphisms and MAFLD was seen. CONCLUSIONS: The new MAFLD definition better reflects the metabolic alterations following GFD in CD population. This new classification could be able to identify patients at higher risk of worse metabolic outcome, who need a close multidisciplinary approach for their multisystemic disease.

Treatment-based risk stratification of infections in inflammatory bowel disease: A comparison between anti-tumor necrosis factor-α and nonbiological exposure in real-world setting.

BACKGROUND AND AIM: Infective issues about anti-tumor necrosis factor (TNF)-α agents in inflammatory bowel disease (IBD) remain controversial, especially when compared with nonbiological treatments. This study aimed to evaluate the incidence and prevalence of several infections in anti-TNF-α-exposed patients compared with nonbiological treatments. METHODS: All naïve IBD subjects treated with anti-TNF-α and matched nonbiologic-exposed patients were included. RESULTS: Among 3453 patients in the database, 288 anti-TNF-α-exposed subjects and 288 nonbiologic-exposed IBD controls met inclusion criteria. Fifty-eight infections (20.1%) occurred during anti-TNF-α treatment versus 23 (8%) in the matched group (odds ratio [OR] 2.9, P < 0.001) (incidence 5.72 vs 0.96/100 patient-years, incidence ratio [IR] 6, P < 0.001). IR was higher for anti-TNF-α versus mesalamine/sulfasalazine (IR 40.8, P < 0.001), similar to azathioprine/6-mercaptopurine/methotrexate (IR 0.78, P = 0.32) and lower than corticosteroids (IR 0.05, P < 0.001). The incidence rate of serious infections was 1.3 in the anti-TNF-α-exposed versus 0.38/100 patient-years in nonexposed subjects (IR 3.44, P = 0.002), without significant difference between anti-TNF-α and azathioprine/6-mercaptopurine/methotrexate (1.3 vs 3.03/100 patient-years, IR 0.43, P = 0.1). Predictors of infections in anti-TNF-α-exposed patients were concomitant use of systemic steroids (OR 1.9, P = 0.02) or azathioprine (OR 2.6, P = 0.01) and a body mass index < 18.5 at time of infection (OR 2.2, P = 0.01). CONCLUSIONS: The risk of developing infections during anti-TNF-α therapy remains high, although not dissimilar to that found for other immunosuppressants, while concomitant immunosuppression and malnutrition appear the most important causes of infection.

Effect of Gliadin Stimulation on HLA-DQ2.5 Gene Expression in Macrophages from Adult Celiac Disease Patients.

Macrophages play an important role in the pathogenesis of celiac disease (CD) because they are involved in both inflammatory reaction and antigen presentation. We analyzed the expression of CD-associated HLA-DQ2.5 risk alleles on macrophages isolated by two cohorts of adult patients, from the U.S. and Italy, at different stages of disease and with different genotypes. After isolating and differentiating macrophages from PBMC, we assessed the HLA genotype and quantified the HLA-DQ2.5 mRNAs by qPCR, before and after gliadin stimulation. The results confirmed the differences in expression between DQA1*05:01 and DQB1*02:01 predisposing alleles and the non-CD associated alleles, as previously shown on other types of APCs. The gliadin challenge confirmed the differentiation of macrophages toward a proinflammatory phenotype, but above all, it triggered an increase of DQA1*05:01 mRNA, as well as a decrease of the DQB1*02:01 transcript. Furthermore, we observed a decrease in the DRB1 genes expression and a downregulation of the CIITA transactivator. In conclusion, our findings provide new evidences on the non-coordinated regulation of celiac disease DQ2.5 risk genes and support the hypothesis that gliadin could interfere in the three-dimensional arrangement of chromatin at the HLA locus.

The impact of a dedicated contact centre on the clinical outcome of patients with inflammatory bowel disease during the COVID-19 outbreak.

BACKGROUND: With the interruption of elective activity during the coronavirus disease 2019 (COVID-19) pandemic, a reorganisation of health care for patients with inflammatory bowel disease (IBD) was warranted. We aimed to investigate the effectiveness of a dedicated contact centre service (CCS) on the reorganization of a high-volume IBD centre and on the continuity of care during the COVID-19 outbreak. METHODS: We compared the CCS services provided to 3680 IBD patients and clinical outcomes before (January-February 2020) and during (March-April 2020) the COVID-19 period. We further included, as comparator, data from March to April of the previous year (2019). RESULTS: During the outbreak, the CCS received an increase of 10.2% of contacts, from 881, in January-February 2020, to 971 (p = 0.02). An increase of 6% in CCS activities was also reported in comparison with March-April 2019 (from 914 to 971 in March-April 2020, p = 0.71). Before COVID-19, in both periods most contacts (67% in January-February 2020 and 60% in March-April 2019) required information about clinical activity, while fewer (33% in January-February 2020 and 40% in March-April 2019) requested logistic information. During the pandemic, most contacts (65.1%) asked to speak with a physician, 23.7% asked for information, while 11.1% wanted to cancel/postpone their appointments. Among all the information, 66% concerned COVID-19. In March-April 2020, 259 outpatient visits were booked, but were all replaced by phone consultations. No difference was detected in the number of intravenous biological administrations (307 versus 296, p = 0.64), surgeries (10 versus 9, p = 0.82) and urgent hospitalisations (10 versus 12, p = 0.67) before and during the COVID-19. CONCLUSION: The CCS was an effective tool in the reorganization of the IBD centre. Scheduled visits were replaced by phone calls. The main clinical outcomes were maintained in the COVID-19 period. Virtual follow-up using the CCS could be implemented after the pandemic to optimise the resources of the IBD centre.