Fernanda Cristofori

Non-Celiac Gluten Sensitivity: The New Frontier of Gluten Related Disorders

Non Celiac Gluten sensitivity (NCGS) was originally described in the 1980s and recently a “re-discovered” disorder characterized by intestinal and extra-intestinal symptoms related to the ingestion of gluten-containing food, in subjects that are not affected with either celiac disease (CD) or wheat allergy (WA). Although NCGS frequency is still unclear, epidemiological data have been generated that can help establishing the magnitude of the problem. Clinical studies further defined the identity of NCGS and its implications in human disease. An overlap between the irritable bowel syndrome (IBS) and NCGS has been detected, requiring even more stringent diagnostic criteria. Several studies suggested a relationship between NCGS and neuropsychiatric disorders, particularly autism and schizophrenia. The first case reports of NCGS in children have been described. Lack of biomarkers is still a major limitation of clinical studies, making it difficult to differentiate NCGS from other gluten related disorders. Recent studies raised the possibility that, beside gluten, wheat amylase-trypsin inhibitors and low-fermentable, poorly-absorbed, short-chain carbohydrates can contribute to symptoms (at least those related to IBS) experienced by NCGS patients. In this paper we report the major advances and current trends on NCGS.

Fecal Microbiota and Metabolome of Children with Autism and Pervasive Developmental Disorder Not Otherwise Specified

This study aimed at investigating the fecal microbiota and metabolome of children with Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) and autism (AD) in comparison to healthy children (HC). Bacterial tag-encoded FLX-titanium amplicon pyrosequencing (bTEFAP) of the 16S rDNA and 16S rRNA analyses were carried out to determine total bacteria (16S rDNA) and metabolically active bacteria (16S rRNA), respectively. The main bacterial phyla (Firmicutes, Bacteroidetes, Fusobacteria and Verrucomicrobia) significantly (P<0.05) changed among the three groups of children. As estimated by rarefaction, Chao and Shannon diversity index, the highest microbial diversity was found in AD children. Based on 16S-rRNA and culture-dependent data, Faecalibacterium and Ruminococcus were present at the highest level in fecal samples of PDD-NOS and HC children. Caloramator, Sarcina and Clostridium genera were the highest in AD children. Compared to HC, the composition of Lachnospiraceae family also differed in PDD-NOS and, especially, AD children. Except for Eubacterium siraeum, the lowest level of Eubacteriaceae was found on fecal samples of AD children. The level of Bacteroidetes genera and some Alistipes and Akkermansia species were almost the highest in PDD-NOS or AD children as well as almost all the identified Sutterellaceae and Enterobacteriaceae were the highest in AD. Compared to HC children, Bifidobacterium species decreased in AD. As shown by Canonical Discriminant Analysis of Principal Coordinates, the levels of free amino acids and volatile organic compounds of fecal samples were markedly affected in PDD-NOS and, especially, AD children. If the gut microbiota differences among AD and PDD-NOS and HC children are one of the concomitant causes or the consequence of autism, they may have implications regarding specific diagnostic test, and/or for treatment and prevention.

Diagnosis of Non-Celiac Gluten Sensitivity (NCGS): The Salerno Experts' Criteria.

Non-Celiac Gluten Sensitivity (NCGS) is a syndrome characterized by intestinal and extra-intestinal symptoms related to the ingestion of gluten-containing food, in subjects that are not affected by either celiac disease or wheat allergy. Given the lack of a NCGS biomarker, there is the need for standardizing the procedure leading to the diagnosis confirmation. In this paper we report experts’ recommendations on how the diagnostic protocol should be performed for the confirmation of NCGS. A full diagnostic procedure should assess the clinical response to the gluten-free diet (GFD) and measure the effect of a gluten challenge after a period of treatment with the GFD. The clinical evaluation is performed using a self-administered instrument incorporating a modified version of the Gastrointestinal Symptom Rating Scale. The patient identifies one to three main symptoms that are quantitatively assessed using a Numerical Rating Scale with a score ranging from 1 to 10. The double-blind placebo-controlled gluten challenge (8 g/day) includes a one-week challenge followed by a one-week washout of strict GFD and by the crossover to the second one-week challenge. The vehicle should contain cooked, homogeneously distributed gluten. At least a variation of 30% of one to three main symptoms between the gluten and the placebo challenge should be detected to discriminate a positive from a negative result. The guidelines provided in this paper will help the clinician to reach a firm and positive diagnosis of NCGS and facilitate the comparisons of different studies, if adopted internationally.

Celiac Disease and Overweight in Children: An Update

The clinical presentation of celiac disease in children is very variable and differs with age. The prevalence of atypical presentations of celiac disease has increased over the past 2 decades. Several studies in adults and children with celiac disease indicate that obesity/overweight at disease onset is not unusual. In addition, there is a trend towards the development of overweight/obesity in celiac patients who strictly comply with a gluten-free diet. However, the pathogenesis and clinical implications of the coexistence of classic malabsorption (e.g., celiac disease) and overweight/obesity remain unclear. This review investigated the causes and main clinical factors associated with overweight/obesity at the diagnosis of celiac disease and clarified whether gluten withdrawal affects the current trends of the nutritional status of celiac disease patients.

High Rate of Spontaneous Normalization of Celiac Serology in a Cohort of 446 Children With Type 1 Diabetes: A Prospective Study

OBJECTIVE In children with type 1 diabetes mellitus (T1DM), elevated levels of antitissue transglutaminase (anti-tTG) antibody may spontaneously normalize, despite continued consumption of gluten. We aimed to investigate the prevalence of spontaneous normalization of anti-tTG levels and the existence of factors predictive for this outcome. RESEARCH DESIGN AND METHODS All children referred from 2002 to 2012 were screened for celiac disease (CD) at diabetes onset and at specific intervals. In the presence of a high anti-tTG titer or clinical symptoms, children were offered endoscopy, and asymptomatic patients with a low anti-tTG titer were invited to a second serological test after 6 months of eating a gluten-containing diet. RESULTS The study included 446 children. Of these, 65 (14.5%) became positive for celiac serology: 38 (58%) had a persistently elevated anti-tTG titer and 27 (41%) fluctuating anti-tTG titer; 18 (28%) became negative. The prevalence of positive CD autoimmunity and overt CD was 14.3% (95% CI 11–17) and 8.5% (95% CI 5–10), 15- and 8-times higher than the general pediatric population, respectively. Asymptomatic children older than 9.1 years at T1DM onset had the lowest risk to develop CD. CONCLUSIONS Serum anti-tTG levels decreased spontaneously in 40% of children with T1DM and became negative in 20%, despite gluten consumption. This finding supports the hypothesis of a state of temporary positivity of celiac serology in children with diabetes. In absence of clinical symptoms or signs of CD, histological confirmation of the disease and the gluten-free diet should be postponed to avoid unnecessary procedures and reduce an additional psychological burden.

Increased Prevalence of Celiac Disease Among Pediatric Patients With Irritable Bowel Syndrome: A 6-Year Prospective Cohort Study

IMPORTANCE Recurrent abdominal pain is a prevalent health issue in childhood. Clinical criteria (ie, the Rome criteria) have been established to aid diagnosis. Studies of adults have shown an increased prevalence of celiac disease among patients with irritable bowel syndrome (IBS); few data are available with regard to children. OBJECTIVE To assess the prevalence of celiac disease among children with abdominal pain-related functional gastrointestinal disorders classified according to the Rome criteria. DESIGN, SETTING, PARTICIPANTS Six-year (2006-2012) prospective cohort study conducted in a tertiary referral center for the diagnosis and follow-up of gastrointestinal disorders in southern Italy (ie, Bari, Italy). A total of 992 children (42.8% male; median age, 6.8 years) consecutively referred for recurrent abdominal pain by their primary care physicians without previous investigation were evaluated. EXPOSURE Patients were classified according to Rome III criteria as having IBS, functional dyspepsia, functional abdominal pain, or abdominal migraine. MAIN OUTCOMES AND MEASURES Prevalence of celiac disease in each category of abdominal pain-related functional gastrointestinal disorder. Concentrations of IgA, IgA antitissue transglutaminase, and endomysial antibodies were measured, and a duodenal biopsy was performed in case of antibody positivity. RESULTS A total of 992 children were evaluated: 270 were classified as having IBS, 201 as having functional dyspepsia, and 311 as having functional abdominal pain, and 210 children were excluded from the study because they had an organic disorder or some other functional gastrointestinal disorder (not related to abdominal pain). Serologic testing was performed for all 782 children included in the study, and 15 patients tested positive for celiac disease (12 of 270 patients with IBS [4.4%], 2 of 201 patients with functional dyspepsia [1%], and 1 of 311 patients with functional abdominal pain [0.3%]). Children presenting with IBS have a 4 times higher risk of having celiac disease than children without IBS (odds ratio, 4.19 [95% CI, 2.03-8.49]; P < .001). CONCLUSIONS AND RELEVANCE The prevalence of celiac disease among children with IBS is 4 times higher than among the general pediatric population. Rome III classification of abdominal pain-related functional gastrointestinal disorders might help to select children who deserve screening for celiac disease.

Epigenetic Matters: The Link between Early Nutrition, Microbiome, and Long-term Health Development

Epigenetic modifications are among the most important mechanisms by which environmental factors can influence early cellular differentiation and create new phenotypic traits during pregnancy and within the neonatal period without altering the deoxyribonucleic acid sequence. A number of antenatal and postnatal factors, such as maternal and neonatal nutrition, pollutant exposure, and the composition of microbiota, contribute to the establishment of epigenetic changes that can not only modulate the individual adaptation to the environment but also have an influence on lifelong health and disease by modifying inflammatory molecular pathways and the immune response. Postnatal intestinal colonization, in turn determined by maternal flora, mode of delivery, early skin-to-skin contact and neonatal diet, leads to specific epigenetic signatures that can affect the barrier properties of gut mucosa and their protective role against later insults, thus potentially predisposing to the development of late-onset inflammatory diseases. The aim of this review is to outline the epigenetic mechanisms of programming and development acting within early-life stages and to examine in detail the role of maternal and neonatal nutrition, microbiota composition, and other environmental factors in determining epigenetic changes and their short- and long-term effects.

Clinical relevance of esophageal baseline impedance measurement: just an innocent bystander.

Objective: The clinical relevance of esophageal baseline impedance (BI) remains to be determined. In the present study, we explored the impact of gastroesophageal reflux disease (GERD) and esophageal dysmotility on BI. Methods: A total of 18 children with esophageal atresia, 26 children with GERD, and 17 controls prospectively underwent esophagogastroduodenoscopy and pH–impedance monitoring. BI was measured in both proximal and distal esophagus. Gastroesophageal reflux (GER) and bolus transit indicators were defined according to published criteria. Results: Patients with esophageal atresia showed significantly lower proximal and distal BI values (952 [716–1811] &OHgr;; 895 [284–1189] &OHgr;; respectively) compared with those with GERD (3015 [2368–3975] &OHgr;; 2231 [1770–3032] &OHgr;, P < 0.001 and <0.001, respectively) and controls (3699 [3194–4358] &OHgr;; 3522 [2927–3994] &OHgr;, P < 0.001 and <0.001, respectively). Using linear regression, proximal BI strongly correlated with total bolus transit time (r2 = 0.61, P < 0.001) and bolus presence time (BPT; r2 = 0.63, P < 0.001). Distal BI weakly correlated with acid exposure time (r2 = 0.16, P < 0.01) and longstanding reflux episodes (r2 = 0.17, P < 0.01), and strongly correlated with total bolus transit time (r2 = 0.53, P < 0.001) and BPT (r2 = 0.58, P < 0.001). By logistic regression, BPT predicted low proximal BI values (odds ratio [OR] 1.052; P < 0.05), whereas both GER indicators (acid exposure time: OR 1.56, P < 0.05; longstanding reflux episodes: OR 2.8, P < 0.05) and BPT (OR 1.66, P < 0.01) predicted low distal BI values. Conclusions: Along the length of esophagus, both bolus transit variables and GER significantly affect BI. This suggests that BI may merely mirror phenomena occurring within the esophageal lumen or wall, limiting its value as a discrete clinical entity to replace variables already used for assessing both GERD and esophageal dysmotility.

Randomized Double-Blind Placebo-Controlled Crossover Trial for the Diagnosis of Non-Celiac Gluten Sensitivity in Children

Objectives:Non-celiac gluten sensitivity (NCGS) is characterized by intestinal and extra-intestinal symptoms that are related to the ingestion of gluten in subjects who are not affected by either celiac disease (CD) or wheat allergy (WA). In this multicenter study, we aim for the first time to evaluate the prevalence of NCGS in pediatric subjects with chronic functional gastrointestinal symptoms associated with gluten ingestion using a double-blind placebo-controlled (DBPC) gluten challenge with crossover.Methods:Among 1,114 children with chronic gastrointestinal symptoms (negative CD and WA), those exhibiting a positive correlation between symptoms and gluten ingestion were eligible for a diagnostic challenge including the following phases: run-in, open gluten-free diet (GFD) and DBPC crossover gluten challenge. Patients were randomized to gluten (10 g/daily) and placebo (rice starch) for 2 weeks each, separated by a washout week. The gluten challenge was considered positive in the presence of a minimum 30% decrease of global visual analogue scale between gluten and placebo.Results:Out of 1,114 children, 96.7% did not exhibit any correlation with gluten ingestion. Thirty-six children were eligible; after the run-in and open GFD, 28 patients entered the gluten challenge. Eleven children (39.2%; 95% CI: 23.6–53.6%) tested positive.Conclusions:This is the first demonstration of the existence of NCGS in children that reinforce the need for a DBPC for the diagnosis as the diagnosis is ruled out in >60% of cases. The registration identifier in ClinicalsTrials.gov is NCT02431585.

Letter: identication of probiotics by specific strain name

SIRS, We read with interest the paper by Vandenplas on the efficacy of probiotics vs. placebo for acute gastroenteritis in children. However, more precise information is needed regarding the strains used. The joint FAO/WHO Expert Consultation recommended that strains be named according to the International Code of Nomenclature, and be deposited in an internationally recognised culture collection to correctly identify the specific strain that is responsible for a given clinical finding. Indeed, it is a well-established fact that the biological effects of probiotics are strain specific, and that the success of a strain cannot be extrapolated to another strain even within the same species. We believe that is important to stress in scientific publications that probiotics should be defined not only by their genus and species, but also and most importantly by the specific strain name. The fact that a bacterium belongs to a specific genus and species (i.e. Lactobacilli rhamnosus) does not alone confer the same properties of a specific strain (L. GG), which may be of critical importance when studying the biological and clinical effects of probiotic bacteria. The authors state that the symbiotic product tested contains several microorganisms, for which there is evidence of efficacy in reducing the severity and duration of acute diarrhoea in children such as, L. rhamnosus (formerly LGG). However, it remains unclear if the rhamnosus used in the study is the wellknown and characterised LGG, or instead a less titled strain. A simple access to the StrainInfo database (http://www.straininfo.net) shows how numerous are the strains that fall in the genus and species reported in Table 3. It is widely acknowledged that properties from one bacterial strain do not necessarily apply to a close relative as strains can differ considerably in genotype and phenotype. This is even more important in the case of LGG. Kankainen et al. sequenced and compared the genomes of LGG and a different L. rhamnosus and found that there is a 98% average identity (the same between man and a monkey), however, in the 2% of diversity resides a set of genes (spaCBA) encoding three pilin proteins and another gene responsible for the assembly of pilus structures important for colonisation and host interaction.