Vincenzo Villanacci

Randomized Feeding Intervention in Infants at High Risk for Celiac Disease

BACKGROUND A window of opportunity has been suggested for reducing the risk of celiac disease by introducing gluten to infants at 4 to 6 months of age. METHODS We performed a multicenter, randomized, double-blind, placebo-controlled dietary-intervention study involving 944 children who were positive for HLA-DQ2 or HLA-DQ8 and had at least one first-degree relative with celiac disease. From 16 to 24 weeks of age, 475 participants received 100 mg of immunologically active gluten daily, and 469 received placebo. Anti-transglutaminase type 2 and antigliadin antibodies were periodically measured. The primary outcome was the frequency of biopsy-confirmed celiac disease at 3 years of age. RESULTS Celiac disease was confirmed by means of biopsies in 77 children. To avoid underestimation of the frequency of celiac disease, 3 additional children who received a diagnosis of celiac disease according to the 2012 European Society for Pediatric Gastroenterology, Hepatology, and Nutrition diagnostic criteria (without having undergone biopsies) were included in the analyses (80 children; median age, 2.8 years; 59% were girls). The cumulative incidence of celiac disease among patients 3 years of age was 5.2% (95% confidence interval [CI], 3.6 to 6.8), with similar rates in the gluten group and the placebo group (5.9% [95% CI, 3.7 to 8.1] and 4.5% [95% CI, 2.5 to 6.5], respectively; hazard ratio in the gluten group, 1.23; 95% CI, 0.79 to 1.91). Rates of elevated levels of anti-transglutaminase type 2 and antigliadin antibodies were also similar in the two study groups (7.0% [95% CI, 4.7 to 9.4] in the gluten group and 5.7% [95% CI, 3.5 to 7.9] in the placebo group; hazard ratio, 1.14; 95% CI, 0.76 to 1.73). Breast-feeding, regardless of whether it was exclusive or whether it was ongoing during gluten introduction, did not significantly influence the development of celiac disease or the effect of the intervention. CONCLUSIONS As compared with placebo, the introduction of small quantities of gluten at 16 to 24 weeks of age did not reduce the risk of celiac disease by 3 years of age in this group of high-risk children. (Funded by the European Commission and others; PreventCD Current Controlled Trials number, ISRCTN74582487.).

Complete recovery of intestinal mucosa occurs very rarely in adult coeliac patients despite adherence to gluten-free diet

Background  Expected benefits of gluten‐free diet (GFD) in coeliac patients include healing of small intestinal mucosa, but it remains unclear to what extent this benefit is achieved in adults.

The role of glial cells and apoptosis of enteric neurones in the neuropathology of intractable slow transit constipation

Background: Idiopathic slow transit constipation is one of the most severe and often intractable forms of constipation. As motor abnormalities are thought to play an important pathogenetic role, studies have been performed on the colonic neuroenteric system, which rules the motor aspects of the viscus. Aims: We hypothesised that important neuropathological abnormalities of the large bowel are present, that these are not confined to the interstitial cells of Cajal and ganglion cells, and that the previously described reduction of enteric neurones, if confirmed, might be related to an increase in programmed cell death (apoptosis). Patients and methods: Surgical specimens from 26 severely constipated patients were assessed by conventional and immunohistochemical methods. Specific staining for enteric neurones, glial cells, interstitial cells of Cajal, and fibroblast-like cells associated with the latter were used. In addition, gangliar cell apoptosis was evaluated by means of indirect and direct techniques. Data from patients were compared with those obtained in 10 controls. Results: Severely constipated patients displayed a significant decrease in enteric gangliar cells, glial cells, and interstitial cells of Cajal. Fibroblast-like cells associated with the latter did not differ significantly between patients and controls. Patients had significantly more apoptotic enteric neurones than controls. Conclusion: Severely constipated patients have important neuroenteric abnormalities, not confined to gangliar cells and interstitial cells of Cajal. The reduction of enteric neurones may in part be due to increased apoptotic phenomena.

Prevalence and diagnosis of celiac disease in IgA-deficient children.

BACKGROUND Reported frequencies of celiac disease in selective IgA deficiency in childhood vary widely and this is probably due to the different characteristics of the patients studied and to the different criteria used for intestinal biopsy: all patients or only those with symptoms of malabsorption. Diagnosis of celiac disease is of considerable importance in IgA deficiency because of its increased frequency and also because avoidance of dietary gluten permits elimination of the symptoms and complications of celiac disease. OBJECTIVES To obtain a more reliable estimate of the incidence of celiac disease in childhood IgA deficiency jejunal biopsies were performed in 65 consecutively diagnosed IgA-deficient children whose parents consented. Some clinical and laboratory parameters including IgA-antigliadin and IgG-antigliadin antibodies were evaluated to predict their usefulness in selecting IgA-deficient patients for intestinal biopsy. METHODS All IgA-deficient patients had serum IgA levels below 5 mg/dL and salivary IgA below 0.5 mg/dL. Jejunal biopsy was performed using a peroral Watson capsule and IgA-antigliadin and IgG-antigliadin antibodies were performed by an ELISA assay. RESULTS Biopsy findings of severe villous atrophy permitted diagnosis of celiac disease in 7.7% (5/65 children). IgG-antigliadin antibody levels, elevated in 16 patients including all five celiacs, were the best parameter for predicting celiac disease and gave no false negatives. CONCLUSIONS The 7.7% frequency of celiac disease observed in these IgA-deficient children is about 20 times higher than in the general Italian population, and the lowest among the studies biopsying all patients; this is probably attributable to the presence of a substantial proportion of healthy children (20/65) and very few (2/65) with autoimmune disorders. The elevated sensitivity and negative-predictive value of IgG-antigliadin antibodies lead us to suggest that positive IgG-antigliadin antibodies can be used to select IgA-deficient children for jejunal biopsy with a very low probability of missing celiac disease while allowing a drastic reduction in the number of biopsies performed.

Coeliac disease: a histological follow‐up study

Aims:  To assess the histological response to a gluten‐free diet (GFD) in a series of coeliac patients in clinical remission, of different ages and with varying degrees of mucosal damage at diagnosis.

Interstitial cells of Cajal, enteric nerves, and glial cells in colonic diverticular disease

Background: Colonic diverticular disease (diverticulosis) is a common disorder in Western countries. Although its pathogenesis is probably multifactorial, motor abnormalities of the large bowel are thought to play an important role. However, little is known about the basic mechanism that may underlie abnormal colon motility in diverticulosis. Aims: To investigate the interstitial cells of Cajal (the gut pacemaker cells), together with myenteric and submucosal ganglion and glial cells, in patients with diverticulosis. Patients: Full thickness colonic samples were obtained from 39 patients undergoing surgery for diverticulosis. Specimens from tumour free areas of the colon in 10 age matched subjects undergoing surgery for colorectal cancer served as controls. Methods: Interstitial cells of Cajal were assessed using anti-Kit antibodies; submucosal and myenteric plexus neurones and glial cells were assessed by means of anti-PGP 9.5 and anti-S-100 monoclonal antibodies, respectively. Results: Patients with diverticulosis had normal numbers of myenteric and submucosal plexus neurones compared with controls (p  =  0.103 and p  =  0.516, respectively). All subtypes of interstitial cells of Cajal were significantly (p  =  0.0003) reduced compared with controls, as were glial cells (p  =  0.0041). Conclusions: Interstitial cells of Cajal and glial cells are decreased in colonic diverticular disease, whereas enteric neurones appear to be normally represented. This finding might explain some of the large bowel motor abnormalities reported to occur in this condition.

How patchy is patchy villous atrophy?: distribution pattern of histological lesions in the duodenum of children with celiac disease.

Objectives:In celiac disease (CD) the degree of histological damage in the duodenum may vary, but there is some controversy about the coexistence of villous atrophy and normal mucosa in different biopsy sites, i.e., patchy villous atrophy. We prospectively evaluated the degree, frequency, and distribution of histological lesions among different duodenal sites as well as within each duodenal biopsy.Methods:Over the last 4 years, in each patient with suspected CD (positive anti-transglutaminase antibodies), four to five endoscopic biopsies were taken from the duodeno-jejunal flexure/distal duodenum (D3), intermediate duodenum (D2), proximal duodenum (D1), and duodenal bulb (B). Biopsies were subjected to hematoxylin/eosin staining and immunostaining with anti-CD3 monoclonal antibodies for intraepithelial lymphocyte (IEL) count. Duodenal lesions were classified according to Marsh–Oberhuber, and CD was diagnosed according to the European Society of Pediatric Gastroenterology, Hepatology, and Nutrition criteria.Results:Six hundred and eighty-six children did have CD. A degree of villous atrophy was found in 660/686 patients (96.2%), total villous atrophy was present in 550/686 (80.1%), and 320/686 (46.6%) had different lesions at different sites, but none of these patients had entirely normal biopsies. In all, 116 of 686 (16.9%) had variable lesions within the same biopsy, with grade 2+3A being the most frequent association (43%), followed by 2+3A+3B (27%) and 2+3A+3B+3C (22%). All these 116 patients also had histologically normal areas within the same biopsy, but anti-CD3 immunostaining showed that IELs were always increased in such areas. In all the cases, the severity of duodenal lesions significantly increased in an aborad manner (χ2=52.38 with α=0.01 and d.f.=12; P<0.0001). No correlation was found between type and distribution of histologic lesions and clinical presentation of CD.Conclusions:In newly diagnosed CD, some variability of histological lesions can be found, even within the same duodenal biopsy, in which areas of apparently normal mucosa with increased IEL number often exist. We also confirm our previous findings that duodenal lesions may vary among different biopsies; lesion severity has a proximal-to-distal gradient, but no patient has entirely normal duodenal biopsies. The awareness of such histological variability may help establish a correct diagnosis of CD.

Enteric nervous system abnormalities in inflammatory bowel diseases

Abstract  Various studies have described abnormalities of the enteric nervous system (ENS) in tissue samples from patients with chronic idiopathic inflammatory bowel diseases (IBD). The distribution of density of the different cell types of the ENS was however not studied in a systematic way. The aim of this study was to examine the density of neurons, enteroglial cells and interstitial cells of Cajal (ICC) in the different plexuses of the ENS in samples from patients with Crohn’s disease (CD), ulcerative colitis (UC) and controls. Tissue samples from 16 patients with CD (ileum) and 16 patients with UC obtained in involved and non‐involved areas were studied using immunohistochemistry with antibodies directed against neuron‐specific enolase, S100, C‐Kit and CD3. Sections were analysed blindly by two pathologists and the number of positive cells was counted for each type. Overall, an increase was noted for neuronal cell bodies, enteroglia and ICC in the deep muscular plexus in CD. In uninvolved areas of CD patients, the number of enteroglial cells was decreased. In UC, an increase of ICC in the muscularis propria and enteroglial cells was observed in diseased tissue. The study confirms the presence of abnormalities of the different cells of the ENS in IBD. The presence of lesions in samples from uninvolved areas, such as a reduction of enteroglia, supports a pathogenetic role of the ENS.

Intraepithelial lymphocytes in the villous tip: do they indicate potential coeliac disease?

Background: The counting of intraepithelial lymphocytes (IELs) in the villous tips of architecturally normal small bowel biopsy specimens was proposed as a method to measure mucosal infiltration in gluten sensitive patients. Aims: To apply this straightforward method in duodenal biopsy specimens from patients affected by potential coeliac disease (PCD) to verify whether it can discriminate these patients from controls. Methods: Paraffin wax embedded duodenal sections from 11 patients affected by PCD were stained with an antihuman CD3 antibody. Sections from 19 patients affected by treated coeliac disease (TCD) and 17 patients in whom coeliac disease was excluded were stained with the same antibody to serve as controls. The slides were examined blindly. IELs/20 enterocytes in five randomly chosen villous tips were counted. Patients affected by PCD were all on a gluten containing diet. They had an architecturally normal duodenal mucosa and were positive for endomysial antibody. Both TCD and non-coeliac controls were negative for endomysial antibody. Results: The mean villous tip IEL scores were 4.6 (SD, 1.5; range, 1.4–7.8) in non-coeliac controls, 7.9 (SD, 4.0; range, 2.0–18.6) in TCD, and 9.2 (SD, 4.7; range, 5.8–21.8) in patients with PCD. The difference between PCD and non-coeliac controls was significant. Conclusions: This is a very simple and sufficiently reliable method to count IELs. In patients with an architecturally normal duodenal mucosa, the IEL count in villous tips helps to distinguish between patients with PCD and non-coeliac controls.

Biological and Molecular Aspects of Gastroenteropancreatic Neuroendocrine Tumors

Neuroendocrine tumors of the digestive tract are rare entities characterized by significant phenotype differences and traditionally considered to originate from cells of the diffuse endocrine system of the pancreas and gut. Two major categories with significant phenotype and clinical behavior differences are identified as well-differentiated and poorly differentiated tumors. Investigation on the molecular basis of tumor development points to an important role for the multiple endocrine neoplasia syndrome type-1 (MEN1) gene because of its frequent abnormality observed both in well-differentiated and poorly differentiated tumors. Other genes are possibly involved, though the available data need support from studies on larger series of tumors.