Follow-up evaluation and management of anemia in inflammatory bowel disease: A study by the Italian Group for Inflammatory Bowel Diseases (IG-IBD).

BACKGROUND: The RIDART I study found a 13.6% prevalence of anemia in Italian patients with inflammatory bowel disease (IBD); most cases were due to iron-deficiency anemia (IDA). AIMS: To evaluate changes in hemoglobin concentration during a 24-week follow-up of anemic patients with IBD. METHODS: Follow-up laboratory and clinical data were obtained from RIDART I study patients with anemia. Factors affecting hemoglobin concentration, the impact of anemia on fatigue and quality of life (QoL), and its relationship with treatment, disease activity and disease complications were investigated. RESULTS: Hemoglobin was 108 g/L at baseline, increased to 121 g/L at follow-up week 12 (p < 0.001) and then stabilized until week 24, but most patients remained anemic, with IDA, throughout the study. Hemoglobin improvement was greater in patients receiving either oral or parenteral iron supplementation. Following hemoglobin normalization, anemia relapse rate during follow-up was 30%. Oral iron did not cause disease reactivation. Lower follow-up hemoglobin was associated with a higher probability of having active disease, clinical complications, increased fatigue and reduced QoL. CONCLUSIONS: In anemic patients with IBD, anemia represents a long-lasting problem, in most cases persisting for up to 24 weeks, with high relapse rate and a negative impact on fatigue and QoL.

Long-Term Natural History of Autoimmune Gastritis: Results From a Prospective Monocentric Series.

INTRODUCTION: The natural history of autoimmune gastritis (AIG) has been poorly described. In this study, we report the long-term natural history and clinical clustering of the full spectrum of AIG, from the potential to the complicated stage. METHODS: Prospective single-center study conducted in a tertiary referral center. Patients with AIG at any stage (0 = potential; 1 = early; 2 = florid; 3 = severe; and 4 = complicated) were enrolled (January 2000-December 2022). The histopathological evolution, the clinical presentation, and the correlates of evolution of potential AIG were assessed. RESULTS: Four hundred ninety-eight patients with AIG (mean age 56.7 ± 15.2 years, F:M ratio 2.5:1) were included, of whom 93 experienced potential AIG. The maximum disease duration was 27 years (median 18, interquartile range 14-23), while the overall median follow-up was 52 months (interquartile range 12-95). Age was significantly lower in stage 0 compared with that in the other stages. Accidental histologic evidence and hematologic findings were the most common clusters of diagnosis. The overall median rate of progression was 7.29 per 100 persons/yr (95% confidence interval [CI] 6.19-8.59), while the stage-specific rates of progression were 10.85 (stage 0; 95% CI 7.75-15.18), 14.83 (stages 1-2; 95% CI 11.89-18.49), and 2.68 (stage 3; 95% CI 1.88-3.84). Newly onset neoplastic complications at follow-up occurred in 41/483 patients (8.5%; 23 neuroendocrine tumors and 18 epithelial dysplasia). No cases of adenocarcinoma were noticed. Male sex was associated with a greater likelihood of evolving from potential AIG to overt AIG. DISCUSSION: AIG is a progressive disorder, with a virtually absent risk of gastric adenocarcinoma. Patients with potential AIG should be monitored because they carry a high risk of evolving into overt AIG.

Prevalence of Disease-Related Malnutrition and Micronutrients Deficit in Patients with Inflammatory Bowel Disease: A Multicentric Cross-Sectional Study by the GSMII (Inflammatory Bowel Disease Study Group).

BACKGROUND AND AIMS: Inflammatory bowel disease (IBD) patients might experience disease-related malnutrition (DRM), but prevalence and risk factors are not well defined. The primary aim of the study was to define the prevalence of DRM and micronutrient deficiency in IBD patients; the secondary aim was to assess variables related to DRM. MATERIALS AND METHODS: A multicenter, cross-sectional study was performed including consecutive adult IBD patients during a period of 2 weeks. Nutritional status was assessed with the body mass index (BMI) and the Malnutrition Universal Screening Tool. DRM was defined according to European Society for Clinical Nutrition and Metabolism guidelines. RESULTS: Among the 295 enrolled patients, the prevalence of DRM was 23%, with no statistical difference between Crohn's disease and ulcerative colitis. Compared with well-nourished patients, patients with DRM showed higher rate of hospitalization in the previous month, were more often receiving systemic steroids, and had lower hemoglobin, albumin, and prealbumin levels and higher median C-reactive protein levels. At univariate logistic regression, current hospitalization, hospitalization in the previous month, low serum albumin, low BMI, high C-reactive protein, high Crohn's Disease Activity Index, and female sex were variables related to DRM. At the multivariate logistic regression, low BMI, current hospitalization and hospitalization in the previous month were significantly associated with DRM. In 23% of IBD patients, a deficiency of at least 1 micronutrient was observed, with no difference between ulcerative colitis and Crohn's disease. CONCLUSIONS: DRM and microelements malnutrition are frequent conditions in the IBD population. DRM seems to be associated with disease activity and hospitalization.

The Effect of a Gluten-Free Diet on Vitamin D Metabolism in Celiac Disease: The State of the Art.

Celiac disease is a chronic autoimmune disorder involving the small intestine, characterized by villous atrophy, crypt hyperplasia and an increase in intraepithelial lymphocytes. Due to both calcium malabsorption and immune activation, a high prevalence of bone mass derangement is evident in this condition, regardless of the presence of overt malabsorption. Alterations of mineral metabolism are also frequently described, and in this review, the modifications of serum levels of vitamin D are analyzed, according to the available literature on this topic. In untreated patients, secondary hyperparathyroidism is responsible for the hyperconversion of 25-vitamin D into 1,25-vitamin D making mandatory the determination of serum levels of both vitamin metabolites to avoid a wrong diagnosis of vitamin D deficit. A gluten-free diet allows for a normalization of bone and mineral metabolism, reverting these abnormalities and raising some doubts on the need for vitamin supplementation in all the patients. Data available do not support this wide indication, and a complete evaluation of bone and mineral metabolism should be performed to select patients who need this therapeutic approach.

Prevalence, Pathogenesis and Management of Anemia in Inflammatory Bowel Disease: An IG-IBD Multicenter, Prospective, and Observational Study.

BACKGROUND: Anemia is a common extraintestinal manifestation of inflammatory bowel disease (IBD), with a 6% to 74% prevalence and a negative impact on patient survival and quality of life, although the prevalence is apparently declining due to improved disease treatment. We aimed to investigate the prevalence, pathogenesis, and clinical correlates of anemia in Italian patients with IBD. METHODS: A multicenter, prospective, observational study, involving 28 Italian gastroenterology centers, was conducted to investigate the epidemiology and consequences of IBD-associated anemia. Clinical and laboratory data of anemic patients were obtained at study enrolment. RESULTS: Anemia was diagnosed in 737 of 5416 adult IBD outpatients (prevalence 13.6%); females were more commonly affected than males (odds ratio, 1.5; 95% confidence interval [CI], 1.2-1.7) and had more severe anemia. In the majority of cases, anemia was due to iron deficiency (62.5% of cases; 95% CI, 58.3%-66.6%), either isolated or in association with inflammation and/or vitamin deficiencies; anemia of inflammation accounted for only 8.3% of cases. More severe anemia was associated with increasing fatigue and worse quality of life. Only 68.9% of anemic patients with iron deficiency (95% CI, 63.4%-73.8%) and 34.6% of those with vitamin deficiencies (95% CI, 26.2%-44.2%) were properly treated with supplementation therapy. CONCLUSIONS: In Italy, the prevalence of IBD-associated anemia is lower than previously reported. Anemia of IBD is most commonly due to iron deficiency and contributes to fatigue and poor quality of life, but remains untreated in a large proportion of patients with iron and/or vitamin deficiencies. This study is registered at clinicaltrials.gov as NCT02872376.

The prevalence of inflammatory bowel disease­associated anemia is 13.6%. The prevalence is higher among females younger than 50. Anemia is usually due to iron deficiency and adversely affects fatigue and quality of life. Many patients with iron or vitamin deficiency (31% and 65%, respectively) remain untreated.

Pathophysiology and therapeutic management of anemia in gastrointestinal disorders.

INTRODUCTION: Anemia is a common complication of gastrointestinal (GI) disorders, with a prevalence up to 60% in celiac disease (CeD) and inflammatory bowel disease (IBD). Iron deficiency anemia (IDA) is the most prevalent form of anemia in these conditions, but chronic inflammation and vitamin B12 deficiency represent other common contributing mechanisms, especially in IBD. AREAS COVERED: We discuss the pathogenesis of anemia in various medical GI disorders, the sometime problematic distinction between IDA, anemia of inflammation (AI) and the association of the two, and therapeutic and preventive measures that can be useful for the management of anemia in GI disorders. Unfortunately, with the exception of IDA and AI in IBD, large RCT concerning the treatment of anemia in GI disorders are lacking. EXPERT OPINION: Anemia management strategies in GI disorders are outlined, with a focus on the main prevention, diagnostic, and therapeutic measures. Specific problems and situations such as the role of gluten-free diet for IDA treatment in CeD, the choice between oral and parenteral supplementation of iron or vitamin B12 in carential anemias, the use of endoscopic procedures to stop bleeding in intestinal angiodysplasia and preventive/treatment strategies for NSAID-associated GI bleeding are discussed.

Multidimensional Prognostic Index Predicts Clinical Outcome and Mortality in Hospitalised Older Patients with Diverticular Disease.

INTRODUCTION: The Multidimensional Prognostic Index (MPI) is a validated tool for assessing mortality risk in hospitalised patients. We aimed to evaluate whether the MPI predicted mortality and the risk of developing diverticular disease (DD) complications in older patients. METHODS: This is a multicentre study conducted in January 2016-March 2018. All patients with DD aged 65 years and older were included. Patients were stratified into three groups according to MPI groups (1, low risk; 2, moderate risk; 3, high risk). Risk of developing DD complications and mortality rate were assessed. Bivariate models were fitted. RESULTS: One hundred hospitalised patients with DD (mean age 77.9 ± 10.6 years, 53 female patients) were included. Patients with higher MPI groups were more likely to develop DD complications. In particular, 12 (46.2%), 21 (52.5%), and 28 (82.4%) patients with complicated DD were distributed to the MPI 1, MPI 2, and MPI 3 groups (p = 0.0063), respectively. Two patients died in the MPI 1, 4 in the MPI 2, and 29 in the MPI 3 group, with mortality rates of 4.0 per 100 person-year (95% confidence interval [CI] 1.0-15.9), 5.6 (95% CI 2.1-15.0), and 89.2 (95% CI 62-130), respectively (log-rank test p < 0.001). In bivariate analysis, after adjustment for age >80 years, Charlson Comorbidity Index >4, DD complications, and the presence of thromboembolism, higher MPI group was independently associated with higher mortality. Those in the MPI 3 group experienced a greater risk of 1-year hospital readmission (p < 0.001). CONCLUSION: MPI predicted mortality in patients with DD and also correlated with the risk of developing DD complications. Studies focussing on possible pathophysiological mechanisms between DD complications and MPI are needed.

Validation of the Italian translation of the perceived stigma scale and resilience assessment in inflammatory bowel disease patients.

BACKGROUND: Stigmatization is the separation of an individual from a group due to aspects that make them different. Resilience may in turn influence the perception of stigma. Patients with inflammatory bowel disease (IBD) are susceptible to stigma, although data are very limited. AIM: To validate an Italian translation of the IBD perceived stigma scale (PSS) in relation to patients' resilience. METHODS: Consecutive IBD outpatients were prospectively enrolled (December 2018-September 2019) in an Italian, tertiary referral, IBD center. Clinical and demographic data were collected. Stigma and resilience were evaluated through the IBD-PSS and the 25-item Connor-Davidson Resilience Scale, respectively. The International Quality of Life Assessment Project approach was followed to translate the IBD-PSS into Italian and to establish data quality. Higher scores represent greater perceived stigma and resilience. Multivariable analysis for factors associated with greater stigma was computed. RESULTS: Overall, 126 IBD patients (mean age 46.1 ± 16.9) were enrolled. The International Quality of Life Assessment criteria for acceptable psychometric properties of the scale were satisfied, with optimal data completeness. There was no ceiling effect, whilst floor effect was present (7.1%). The discriminant validity and the internal consistency reliability were good (Cronbach alpha = 0.87). The overall internal consistency was 95%, and the test-retest reliability was excellent 0.996. The median PSS score was 0.45 (0.20-0.85). Resilience negatively correlated with perceived stigma (Spearman's correlation = -0.18, 95% confidence intervals: -0.42-0.08, P = 0.03). CONCLUSION: We herein validated the Italian translation of the PSS scale, also demonstrating that resilience negatively impacts perceived stigma.

Impact of in-hospital intravenous iron supplementation on red blood cell transfusions: experience from an Internal Medicine Unit.

BACKGROUND: Pharmacological treatment of iron deficiency anaemia can reduce red blood cell (RBC) transfusions. Intravenous iron provides a more effective and quicker correction of iron deficiency anaemia than oral iron, and third-generation high-dose intravenous iron formulations allow the complete correction of iron deficiency with just one or two drug infusions, thus facilitating iron supplementation therapy and reducing transfusion requirement. MATERIAL AND METHODS: In an observational, retrospective study we compared RBC transfusion requirement during hospitalisation and within 3 months of hospital discharge in 88 patients with iron deficiency anaemia treated with high-dose ferric carboxymaltose and in 85 patients treated with ferric gluconate while hospitalised in the Internal Medicine unit of our Institution. RESULTS: Ferric carboxymaltose reduced the number of RBC units given to each transfused patient during hospitalisation (1.81±0.84 vs 2.39±1.49, p=0.011). At hospital discharge, fewer ferric carboxymaltose patients were prescribed home therapy with iron. No differences between treatment groups were observed in the proportion of patients or the number of RBC units transfused within 3 months of discharge. At one month from discharge, however, only 2 ferric carboxymaltose patients had been transfused compared with 7 ferric gluconate patients (p=0.078). Patients transfused post-discharge were more likely to have an underlying malignancy and/or higher serum creatinine concentrations. DISCUSSION: Treatment with ferric carboxymaltose reduced the number of RBC units per transfused patient. Larger studies are required to define risk factors associated with post-discharge transfusion requirement and to establish if home therapy with iron will reduce subsequent transfusions in patients treated with ferric carboxymaltose.

Human Cytomegalovirus and Epstein-Barr virus specific immunity in patients with ulcerative colitis.

Human Cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) are endowed with the ability of establishing lifelong latency in human hosts and reactivating in immunocompromised subjects, including patients suffering from ulcerative colitis (UC). We, therefore, aimed to investigate virus-specific immunity in UC patients. A cohort of 24 UC patients (14 responders and 10 refractory to therapy) and 26 control subjects was prospectively enrolled to undergo virus-specific serology (by ELISA assay) and assessment of both CD4+ and CD8+ virus-specific T-cell response (by interferon-γ enzyme-linked immunospotanalysis). In parallel, mucosal viral load was determined by quantitative real-time PCR and the values were correlated with both clinical and endoscopic indexes of activity. For statistics, the t-test, Mann-Withney test, Fisher's exact test and Spearman rank correlation test were applied; p < 0.05 was considered significant. EBV-specific CD4+ and CD8+ T-cell responses were significantly lower in UC patients compared to controls (p < 0.0001 and p = 0.0006, respectively), whereas no difference was found for HCMV-specific T-cell response. When dividing the UC group according to response to therapy, both responders and refractory UC patients showed a deficient EBV-specific CD4+ T-cell response with respect to controls (p < 0.04 and p = 0.0003, respectively). Moreover, both EBV and HCMV mucosal loads were significantly higher in refractory UC than in responders and controls (p = 0.007 and 0.003; and p = 0.02 and 0.001, respectively), and correlated with activity indexes. Steroid therapy seemed the main risk factor for triggering EBV colitis. Finally, no cases of IgM positivity were found in the study population. An impaired EBV-specific immunity was clearly evident in UC patients, mostly in those refractory to therapy. The ELISPOT assay may serve as new tool for quantifying and monitoring virus-specific T-cell immunity in UC.

Validation of the Red Flags Index for Early Diagnosis of Crohn's Disease: A Prospective Observational IG-IBD Study Among General Practitioners.

INTRODUCTION: Diagnostic delay >12 months is frequent in Crohn's disease [CD]. Recently, the International Organization for Inflammatory Bowel Disease [IO-IBD] developed a tool to identify early CD and reduce diagnostic delay. Subjects with an index ≥8 are more likely to have suspected CD (odds ratio [OR] 205, p <0.0001). We aimed to validate this questionnaire at the community level in patients seen by the general practitioners [GPs] in two large areas of Lombardy, Italy. METHODS: Consecutive adult patients referring to the GP were screened. The GPs administered the Red Flags [RF] questionnaire to the eligible patients. All patients were referred to the nearest participating centre to confirm or exclude the diagnosis of CD. Sensitivity, specificity, and positive and negative predictive values [PPV, NPV] of the RF index [RFI] were calculated. Patients lost to follow-up after the first gastroenterological visit were analysed using a non-responder imputation, assuming they were negative for CD diagnosis. RESULTS: From November 2016 to November 2019, 112 patients were included. A total of 66 subjects [59%] completed the study after the first gastroenterological visit. The prevalence of CD was 3.6% in the study population [4/112]. The RF index had 50% sensitivity, 58% specificity, 4% PPV, and 97% NPV. A combined diagnostic strategy with faecal calprotectin [FC] [RFI ≥8 and/or FC >250 ng/g] resulted in significantly improved accuracy: sensitivity 100% [29-100%], specificity 72% [55-85%], PPV = 21% [5-51%], NPV = 100% [88-100%]. CONCLUSIONS: The RF Index combined with FC is a valid tool to identify patients with high probability of having CD at early stage.

Impact of COVID-19 on liver function: results from an internal medicine unit in Northern Italy.

Little is known regarding coronavirus disease 2019 (COVID-19) clinical spectrum in non-Asian populations. We herein describe the impact of COVID-19 on liver function in 100 COVID-19 consecutive patients (median age 70 years, range 25-97; 79 males) who were admitted to our internal medicine unit in March 2020. We retrospectively assessed liver function tests, taking into account demographic characteristics and clinical outcome. A patient was considered as having liver injury when alanine aminotransferase (ALT) was > 50 mU/ml, gamma-glutamyl transpeptidase (GGT) > 50 mU/ml, or total bilirubin > 1.1 mg/dl. Spearman correlation coefficient for laboratory data and bivariable analysis for mortality and/or need for intensive care were assessed. A minority of patients (18.6%) were obese, and most patients were non- or moderate-drinkers (88.5%). Liver function tests were altered in 62.4% of patients, and improved during follow-up. None of the seven patients with known chronic liver disease had liver decompensation. Only one patient developed acute liver failure. In patients with altered liver function tests, PaO2/FiO2 < 200 was associated with greater mortality and need for intensive care (HR 2.34, 95% CI 1.07-5.11, p = 0.033). To conclude, a high prevalence of altered liver function tests was noticed in Italian patients with COVID-19, and this was associated with worse outcomes when developing severe acute respiratory distress syndrome.

Preventing Infections by Encapsulated Bacteria Through Vaccine Prophylaxis in Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD), which comprises ulcerative colitis and Crohn's disease, is an immune-mediated, chronic-relapsing, disabling disorder which is associated with increased mortality and poor patients' quality of life. Patients with IBD are at increased risk of infections for many reasons. In fact, IBD often requires a lifelong immunosuppressive and/or biologic therapy, both commonly associated with respiratory and opportunistic infections, but also gastrointestinal, urinary tract infections, and sepsis. Moreover, impaired spleen function has been found in a considerable proportion of IBD patients, further increasing the risk of developing infections sustained by encapsulated bacteria, such as S. pneumoniae, H. influenzae, and N. meningitidis. Finally, comorbidities and surgery represent additional risk factors for these patients. Despite the availability of vaccinations against the most common serotypes of encapsulated bacteria, uncertainties still exist regarding a proper vaccination strategy and the actual effectiveness of vaccinations in this particular setting. Aim of this narrative review is to focus on the broad topic of vaccinations against encapsulated bacteria in IBD patients, discussing the clinical impact of infections, predisposing factors, vaccinations strategies, and unmet research and clinical needs.

Comprehensive nutritional assessment in short bowel syndrome with chronic renal failure on teduglutide therapy: A case report.

We report the case of a 62-y-old woman with short bowel syndrome (SBS) and chronic renal failure, successfully treated with teduglutide, who underwent comprehensive systematic nutritional assessment including bioelectrical impedance vectorial analysis (BIVA). The patient did not tolerate the attempt of gradual suspension of parenteral nutrition (PN), bumping into the worsening of nutritional status and renal function. She was declared eligible for teduglutide, a glucagonlike peptide 2 analog that stimulates structural and functional intestinal adaptation and increases nutrient and fluid absorption. To date, there is no standardized nutritional management protocol for PN-dependent SBS patients treated with teduglutide. We here report our first 1-y follow-up data. The patient underwent comprehensive systematic nutritional assessment initially every 2 wk, then monthly. It included handgrip strength (HGS), blood tests (particularly serum creatinine, estimated glomerular filtration rate, urea, electrolytes, micronutrients, serum albumin), fluid intake, urine output, quality-of-life (QoL) evaluation, and BIVA, which estimates fat-free mass (FFM) and measures phase angle (PhA) and hydration status. At treatment initiation, the patient was on PN 3 d/wk. After 3 mo, she was weaned off PN. At 1 y, weight and serum albumin were reduced (-7.5 kg and -0.6 g/dL, respectively); FFM, PhA, and HGS slightly decreased; hydration status and renal function were preserved; and QoL subtly improved. No relevant clinical complications or metabolic imbalances occurred. The inclusion of BIVA in the comprehensive systematic nutritional assessment of SBS patients treated with teduglutide could be proposed for appropriate and safe management, particularly in the presence of renal impairment.

Mortality rate and risk factors for gastrointestinal bleeding in elderly patients.

BACKGROUND: Gastrointestinal bleeding (GIB) is burdened by high mortality rate that increases with aging. Elderly patients may be exposed to multiple risk factors for GIB. We aimed at defining the impact of GIB in elderly patients. METHODS: Since 2008, samples of elderly patients (age ≥ 65 years) with multimorbidity admitted to 101 internal medicine wards across Italy have been prospectively enrolled and followed-up (REPOSI registry). Diagnoses of GIB, length of stay (LOS), mortality rate, and possible risk factors, including drugs, index of comorbidity (Cumulative Illness Rating Scale [CIRS]), polypharmacy, and chronic diseases were assessed. Adjusted multivariate logistic regression models were computed. RESULTS: 3872 patients were included (mean age 79 ±â€¯7.5 years, F:M ratio 1.1:1). GIB was reported in 120 patients (mean age 79.6 ±â€¯7.3 years, F:M 0.9:1), with a crude prevalence of 3.1%. Upper GIB occurred in 72 patients (mean age 79.3 ±â€¯7.6 years, F:M 0.8:1), lower GIB in 51 patients (mean age 79.4 ±â€¯7.1 years, F:M 0.9:1), and both upper/lower GIB in 3 patients. Hemorrhagic gastritis/duodenitis and colonic diverticular disease were the most common causes. The LOS of patients with GIB was 11.7 ±â€¯8.1 days, with a 3.3% in-hospital and a 9.4% 3-month mortality rates. Liver cirrhosis (OR 5.64; CI 2.51-12.65), non-ASA antiplatelet agents (OR 2.70; CI 1.23-5.90), and CIRS index of comorbidity >3 (OR 2.41; CI 1.16-4.98) were associated with GIB (p < 0.05). CONCLUSIONS: A high index of comorbidity is associated with high odds of GIB in elderly patients. The use of non-ASA antiplatelet agents should be discussed in patients with multimorbidity.

The effect of gluten on intestinal fermentation, gastric and gallbladder emptying in healthy volunteers.

BACKGROUND: The relationship between gluten ingestion and gastrointestinal tract function is a matter of debate. AIM: We analysed the effect of gluten on gastric and gallbladder emptying and intestinal fermentation in healthy volunteers. METHODS: Ultrasound measurement of gastric and gallbladder emptying after both gluten-containing and gluten-free meals was performed in 18 volunteers (8 women, age 25.0±2.5 years; BMI 22±1.9). Breath hydrogen excretion after a gluten-containing meal, a gluten-free meal and a gluten-free meal with added gluten powder was measured in 16 volunteers (10 women, age 25.2±2.7 years; BMI 22±1.8). The severity of symptoms was monitored. RESULTS: Gluten presence in the meals was not recognised. Gastric emptying time was 81.6±13.8min after gluten-containing and 73.9±21.6min after gluten-free meals (p=0.11). Percentage ejection fraction after gluten-containing meals was 60±9% and 60.6±6% after gluten-free meals (p=0.68). Peak and cumulative hydrogen excretion were significantly higher after gluten-containing than after gluten-free meals (peak: 12.5±7.3 vs 6.5±5.1 parts-per-million, p<0.01; and cumulative: 2319±1720 vs 989±680 parts-per-million/minute, respectively; p<0.01). Adding gluten powder to the gluten-free meal did not modify fermentation. Symptoms were mild and not different after the meals. CONCLUSIONS: In healthy volunteers, gluten may induce gastrointestinal alterations. Further studies are needed to clarify which patients could benefit from dietary modification.

Breath Methane Excretion Is not An Accurate Marker of Colonic Methane Production in Irritable Bowel Syndrome.

OBJECTIVES: The role of colonic methane production in functional bowel disorders is still uncertain. In small samples of irritable bowel syndrome (IBS) patients, it was shown that methane breath excretion correlates with clinical presentation and delayed gastrointestinal transit time. The aim of this study was to evaluate the relationship between intestinal production and breath excretion of CH4 and to correlate CH4 production with the presence and the severity of symptoms, in a large cohort of IBS patients and in a group of healthy volunteers. METHODS: A group of 103 IBS patients and a group of 28 healthy volunteers were enrolled. The presence and severity of symptoms and gastrointestinal transit were evaluated in all subjects, who underwent breath H2/CH4 measurement for 7 h after lactulose to identify breath excretors of these gases; H2 and CH4 were also measured in rectal samples to identify colonic producers. Cumulative H2 and CH4 excretion and production were evaluated by the area under the time-concentration curve calculation (AUC). RESULTS: In IBS patients, CH4 was detected in rectal samples in 48 patients (47%), but only 27 of them (26% of the 103 enrolled patients) excreted this gas with breath. In CH4 producers, the prevalence and severity of symptoms and gastrointestinal transit time were not significantly different with respect to non-producers. IBS subtypes were homogeneously represented in CH4 producers and in non-producers. Healthy volunteers, compared with IBS patients, showed a significantly lower prevalence of CH4 excretion, whereas no difference was found in the prevalence of colonic CH4 production; moreover, in healthy volunteers compared with IBS, CH4 breath excretion and CH4 production were not different in quantitative terms. CONCLUSION: Our data show that colonic CH4 production is not associated with clinical presentation in IBS patients and does not correlate with symptom severity or with gastrointestinal transit time. Clinical inferences based on breath CH4 excretion should undergo an in-depth revision, as this method is not a good marker of CH4 colonic production.