B. Bizzarri

Exploring the Diversity of the Bifidobacterial Population in the Human Intestinal Tract

ABSTRACT Although the health-promoting roles of bifidobacteria are widely accepted, the diversity of bifidobacteria among the human intestinal microbiota is still poorly understood. We performed a census of bifidobacterial populations from human intestinal mucosal and fecal samples by plating them on selective medium, coupled with molecular analysis of selected rRNA gene sequences (16S rRNA gene and internally transcribed spacer [ITS] 16S-23S spacer sequences) of isolated colonies. A total of 900 isolates were collected, of which 704 were shown to belong to bifidobacteria. Analyses showed that the culturable bifidobacterial population from intestinal and fecal samples include six main phylogenetic taxa, i.e., Bifidobacterium longum, Bifidobacterium pseudocatenulatum, Bifidobacterium adolescentis, Bifidobacterium pseudolongum, Bifidobacterium breve, and Bifidobacterium bifidum, and two species mostly detected in fecal samples, i.e., Bifidobacterium dentium and Bifidobacterium animalis subp. lactis. Analysis of bifidobacterial distribution based on age of the subject revealed that certain identified bifidobacterial species were exclusively present in the adult human gut microbiota whereas others were found to be widely distributed. We encountered significant intersubject variability and composition differences between fecal and mucosa-adherent bifidobacterial communities. In contrast, a modest diversification of bifidobacterial populations was noticed between different intestinal regions within the same individual (intrasubject variability). Notably, a small number of bifidobacterial isolates were shown to display a wide ecological distribution, thus suggesting that they possess a broad colonization capacity.

Relationship between baseline impedance levels and esophageal mucosal integrity in children with erosive and non‐erosive reflux disease

Background  Baseline impedance measurement has been reported to be related to esophageal acid exposure and hypothesized to be a marker of microscopic changes of the esophageal mucosa. Aims of the study were to establish whether any relationship existed between the magnitude of intercellular space diameter (ISD) of esophageal mucosa and baseline impedance levels in children with gastro‐esophageal reflux disease (GERD), and to compare baseline impedance levels between children with non erosive (NERD) and erosive (ERD) reflux disease.

Helicobacter pylori Infection in Clinical Practice: Probiotics and a Combination of Probiotics + Lactoferrin Improve Compliance, But Not Eradication, in Sequential Therapy

Background:  Sequential therapy (ST) seems to offer higher success rates than triple therapy (TT) in the eradication of Helicobacter pylori (H. pylori) infection. However, from the standpoint of therapeutic compliance, there is no difference between the two treatments. Adjuvant treatment (especially with probiotics (PB) and lactoferrin (LF)) has often improved compliance and eradication rates in patients subjected to TT, while ST had never been used in association with adjuvants.

Complications of percutaneous endoscopic gastrostomy in children: Results of an Italian multicenter observational study

BACKGROUND Percutaneous endoscopic gastrostomy is the preferred way to achieve an artificial feeding route for patients requiring long-term enteral nutrition. Although the procedure is well-standardized, it carries early and late complications. AIM To establish the mortality and morbidity of this technique in a large cohort of children. METHODS A multi-centre prospective clinical data collection from children undergoing percutaneous endoscopic gastrostomy tube implantation has been conducted from January 2004 to December 2007. Previous abdominal surgery was the only exclusion criterion. Follow-up visits were carried out at 1, 3, 6, 12, and 24 months after the procedure. RESULTS 239 children (males, 55.2%; mean age 6.05±6.1years) were enrolled from nine tertiary Italian centres. Major complications occurred in 8 patients (3.3%). The cumulative incidence of complications was 47.7% at 24 months. The presence of thoraco-abdominal deformity was an independent predictor of complications at 12 months. No risk factors were identified in association to complications during the 1st tube replacement. CONCLUSION In children undergoing percutaneous endoscopic gastrostomy placement minor complications are common, while severe morbidities are rare. Accurate follow up is essential to recognize every complication, in particular when risk factors such as thoraco-abdominal deformity exist.

Usefulness of a serological panel test in the assessment of gastritis in symptomatic children.

Background: Non-invasive methods are advisable for the detection of Helicobacter pylori-related chronic gastritis in pediatric patients. Serum pepsinogens I and II (sPGII and sPGII), gastrin-17 (G-17) and anti-H. pylori antibodies (IgG-Hp) have been proposed as a ‘serological gastric biopsy’. Aim: To assess H. pylori infection and to evaluate gastric mucosa status in a pediatric population by means of serological parameters such as sPGI, sPGII, G-17 and IgG-Hp. Methods: 45 consecutively children evaluated for upper gastrointestinal symptoms were analyzed. All children were submitted to upper gastrointestinal endoscopy with biopsies. Serum samples were analyzed for IgG-Hp, sPGII, sPGI and G-17 (Biohit, Helsinki, Finland). Results: 18 children had H. pylori-related mild or moderate non-atrophic chronic gastritis. They presented significantly higher mean levels of sPGII and of IgG-Hp than negative ones, eitherunder or up to 10 years. sPGI showed significantly increased levels in H. pylori-positive patients only over 10 years. G-17 levels were not different between H. pylori-positive and -negative ones. The best cut-offs of IgG-Hp, sPGII and of product IgG-Hp·sPGII, to identify H. pylori infection, were 30 IU/l, 9 µg/l, and 241 IU/l·µg/l, respectively. The product IgG-Hp·sPGII identified H. pylori infection with a 100% sensitivity, 92% specificity, 90% positive predictive value and 100% negative predictive value. IgG-Hp and IgG-Hp showed a correlation (r = 0.94; p < 0.001). Conclusions: Combined analysis of sPGII and IgG-Hp antibody levels could be recommended as a non-invasive panel for the assessment of H. pylori-related histological alterations of gastric mucosa in childhood.

Italian survey on non-steroidal anti-inflammatory drugs and gastrointestinal bleeding in children

AIM To investigate gastrointestinal complications associated with non-steroidal anti-inflammatory drug (NSAIDs) use in children. METHODS A retrospective, multicenter study was conducted between January 2005 and January 2013, with the participation of 8 Italian pediatric gastroenterology centers. We collected all the cases of patients who refer to emergency room for suspected gastrointestinal bleeding following NSAIDs consumption, and underwent endoscopic evaluation. Previous medical history, associated risk factors, symptoms and signs at presentation, diagnostic procedures, severity of bleeding and management of gastrointestinal bleeding were collected. In addition, data regarding type of drug used, indication, dose, duration of treatment and prescriber (physician or self-medication) were examined. RESULTS Fifty-one patients, including 34 males, were enrolled (median age: 7.8 years). Ibuprofen was the most used NSAID [35/51 patients (68.6%)]. Pain was the most frequent indication for NSAIDs use [29/51 patients (56.9%)]. Seven patients had positive family history of Helicobacter pylori (H. pylori) infection or peptic ulcer, and 12 had associated comorbidities. Twenty-four (47%) out of 51 patients used medication inappropriately. Hematemesis was the most frequent symptom (33.3%). Upper gastrointestinal endoscopy revealed gastric lesions in 32/51 (62%) patients, duodenal lesions in 17 (33%) and esophageal lesions in 8 (15%). In 10/51 (19.6%) patients, a diagnosis of H. pylori gastritis was made. Forty-eight (94%) patients underwent medical therapy, with spontaneous bleeding resolution, while in 3/51 (6%) patients, an endoscopic hemostasis was needed. CONCLUSION The data collected in this study confirms that adverse events with the involvement of the gastrointestinal tract secondary to NSAID use are also common in children.

Management of duodenal-jejunal polyps in children with peutz-jeghers syndrome with single-balloon enteroscopy.

Objectives: Children with Peutz-Jeghers syndrome (PJS) have increased risk of polyp-related complications and emergency laparotomies. The aim of the present study was to assess the efficacy and the safety of endoscopic therapy of small bowel polyps using single-balloon enteroscopy (SBE) in children affected by PJS. Methods: Between January 2010 and December 2011, prospectively consecutive PJS children with polyps >15 mm or polyps actively bleeding previously identified using video capsule endoscopy and magnetic resonance imaging underwent therapeutic SBE. The main outcome measurements were the feasibility, the technical performance, and the safety. Results: A total of 10 children (6 boys; median age 13.7 years, range 5.6–15.6) underwent 23 SBE procedures. Four patients had a history of abdominal surgery. A total of 53 polyps were removed, and 23 of them were >15 mm. The majority of polyps were found in jejunum (85%). The mean insertion depths for antegrade and retrograde approach were 200 ± 80 and 100 ± 50 cm beyond the ileal valve, respectively. The mean procedure time was 75 ± 25 minutes. Mild abdominal pain was reported after 3 procedures. In 1 patient a postpolypectomy perforation occurred. Conclusions: In conclusion, SBE is an effective endoscopic tool for treating small bowel polyps in children with PJS, and well-timed polypectomy may optimize patients’ care, preventing polyp-related complications and emergency laparotomy. Further larger multicenter studies are warranted to accurately determine the safety of therapeutic SBE in children.

CO15 OESOPHAGEAL MUCOSAL DILATED INTERCELLULAR SPACES (DIS): IS IT A REAL ULTRASTRUCTURAL MARKER OF GERD PHENOTYPE? A CHILDREN POPULATION STUDY

Results: All patients under 2 years of age were normal for weight. Between 2 and 20 years, 18/143 (12.6%) were underweight and 48/143 (33.6%) were “at risk”. Over 20 years 6/12 (50.0%) “at risk” and no one was underweight. We confirm the positive relationship between FEV1% and nutritional status (FEV1% M±DS 98.03±24.11 in normal weight vs 67.05±25.67 in underweight; p 20 yrs BMI “at risk” M±DS T0 18.50±9.57 vs T1 20.11±10.52). In patients between 2 and 20 years the percentage of patients less than the 10th BMI percentile and between 10th and 50th BMI percentile decreased from 18/143 to 4/143 (12.6% vs 2.7% p<0.001) and from 48/143 to 34/143 (33.6% vs 23.7%, p<0.001) respectively. Conclusion: Our study confirms the crucial role of an early diagnosis of CF in order to prevent nutritional failure. Individual management with an aggressive nutritional treatment in CF patients in or at highest risk for malnutrition can increase rates of adherence to nutrition recommendation for improving clinical outcomes. References [1] Lai HJ, Shoff SM. Classification of malnutrition in cystic fibrosis: implications for evaluating and benchmarking clinical practice performance. Am J Clin Nutr 2008;88:161–6.