Nigel Reynolds

Clinical trial: the microbiological and immunological effects of synbiotic consumption - a randomized double-blind placebo-controlled study in active Crohn's disease.

Aliment Pharmacol Ther 2010; 32: 872–883

A Brief Report of the Epidemiology of Obesity in the Inflammatory Bowel Disease Population of Tayside, Scotland

Aim: Obesity in inflammatory bowel disease (IBD), particularly Crohn’s disease (CD), has previously been considered unusual (3%). CD patients who are obese tend to have increased perianal complications and a higher level of disease activity on an annual basis. Obesity in Scotland has been documented to have increased over the last decade, and over half all men and women in Scotland are now considered to be overweight. This study aims to assess obesity prevalence in the IBD community in Tayside, Scotland. Methods: All IBD patients (n = 1,269) were considered for inclusion. Inclusion criteria required a weight measurement taken from the preceding 12 months and a height measurement within the last decade. 489 patients were included in the analysis. Results: 18% of the Tayside IBD population were obese in comparison to approximately 23% of the Scottish population on a whole. A further 38% of patients were over-weight, the same percentage as the general population. In the overweight and obese ulcerative colitis patients there were higher levels of surgery, but the converse was true in the CD group, where the normal-weight group had the highest levels of surgery. There were significantly more obese men and women with CD than with ulcerative colitis (P = 0.05). Conclusion: Obesity prevalence has increased in IBD patients. This is significant because of the known increased levels of postoperative complications, perianal disease and requirement for more aggressive medical therapy. Research needs to be done to look at the effects of obesity on the co-morbid associations of other diseases with IBD, in particular colorectal cancer, and to ascertain whether or not screening frequency should be altered depending on BMI.

Effect of pH on an In Vitro Model of Gastric Microbiota in Enteral Nutrition Patients

ABSTRACT Patients with dysphagia due to oropharyngeal disease or cerebrovascular accident require long-term nutritional support via enteral feeding, which often results in microbial overgrowth in the upper gastrointestinal (GI) tract. Gastric acid is the primary innate defense mechanism in the stomach and has been assumed to provide an effective barrier to microbial colonization at pH values of <4. To evaluate the efficacy of gastric acid as a barrier to overgrowth, the microbiota of gastric and duodenal aspirates was assessed by culturing methods. Additionally, a fermentor-based model incorporating enteral nutrition tubing of the gastric microbiota of enteral nutrition (EN) patients was constructed to assess the effect of pH on the microbiota. Results showed that gastric acidity had a relatively small effect on the numbers of microorganisms recovered from intestinal aspirates but did influence microbiota composition. Similarly, at pH 3 in the fermentor, a complex microbiota developed in the planktonic phase and in biofilms. The effect of pH on microbiota composition was similar in aspirates and in the fermentors. Candidas and lactobacilli were aciduric, while recoveries of Escherichia coli and Klebsiella pneumoniae decreased as pH was reduced, although both were still present in significant numbers at pH 3. Only Staphylococcus aureus and Bifidobacterium adolescentis persisted at higher pH values both in vitro and in vivo. Lactate and acetate were the main organic acids detected in both aspirates and fermentors. These data show that the simulator used in this investigation was capable of modeling the effects of environmental influences on the upper GI microbiota of EN patients and that gastric pH of <4 is not sufficient to prevent microbial overgrowth in these individuals.

Effect of pH and Antibiotics on Microbial Overgrowth in the Stomachs and Duodena of Patients Undergoing Percutaneous Endoscopic Gastrostomy Feeding

ABSTRACT Enteral nutrition via a percutaneous endoscopic gastrostomy (PEG) tube is often part of management in patients with dysphagia due to neurological or oropharyngeal disease. Gastrostomy placement can affect normal innate defense mechanisms in the upper gut, resulting in bacterial overgrowth. In this study microbiological investigations were done with gastric and duodenal aspirates from 20 patients undergoing PEG tube placement and PEG tubes from 10 patients undergoing tube replacement. Aspirate and PEG tube microbiotas were assessed by using viable counts and selective solid media followed by aerobic and anaerobic incubation to assess cell viabilities. The antibiotic susceptibility profiles of the isolates were determined by the disk diffusion method, and gas chromatography was used to study the bacterial metabolic products in the aspirates. The aspirates and PEG tubes contained mainly streptococci, staphylococci, lactobacilli, yeasts, and enterobacteria. Enterococci were detected only in PEG tube biofilms and not in aspirates. Gastric pH affected the composition of the aspirate microbiotas but not the total microbial counts. Staphylococci, Escherichia coli, and Candida spp. were isolated only from antibiotic-treated patients, despite the sensitivities of the bacteria to the agents used. Antibiotic treatment had no effect on the incidence of infection or the length of hospital stay in these patients.

Assessment of distal tip position of long-term central venous feeding catheters using transesophageal echocardiology.

BACKGROUND Central vein catheter position is a vital element in promoting longevity and minimizing adverse events associated with long-term parenteral nutrition. Traditionally, position has been verified using a chest radiograph. However, this mode of assessment has limitations as the catheter is placed in a dynamic system subject to forces from changes in posture and diaphragmatic movement. METHODS We compared the reported position using a chest x-ray compared with assessment using transesophageal echocardiology (TOE) in 9 patients receiving home parenteral nutrition. The x-ray was reported by a radiologist unaware of the study. RESULTS There were discordant results in 7 of the 9 cases with catheter tip placed in the right atrium or impinging in the tricuspid valve which was not evident from the chest x-ray. TOE offered greater information of catheter tip position and relationship to adjacent anatomy. CONCLUSIONS Further work is required but this observational study suggests guidelines suggesting the use of a chest radiograph to confirm catheter position may need to be re-assessed.

Synbiotic consumption changes the metabolism and composition of the gut microbiota in older people and modifies inflammatory processes: a randomised, double-blind, placebo-controlled crossover study

Ageing can result in major changes in the composition and metabolic activities of bacterial populations in the large gut and an impaired immune system.

Microbiological and immunological effects of enteral feeding on the upper gastrointestinal tract.

Enteral feeding via a percutaneous endoscopic gastrostomy tube is required for nutritional support in patients with dysphagia. Enteral tube feeding bypasses the innate defence mechanisms in the upper gastrointestinal tract. This study examined the surface-associated microbial populations and immune response in the gastric and duodenal mucosae of eight enteral nutrition (EN) patients and ten controls. Real-time PCR and fluorescence in situ hybridization were employed to assess microbiota composition and mucosal pro-inflammatory cytokine expression. The results showed that EN patients had significantly higher levels of bacterial DNA in mucosal biopsies from the stomach and duodenum (P<0.05) than the controls, and that enterobacteria were the predominant colonizing species on mucosal surfaces in these individuals. Expression of the pro-inflammatory cytokines interleukin (IL)-1α, IL-6 and tumour necrosis factor-α was significantly higher in gastric and small intestinal mucosae from patients fed normal diets in comparison with those receiving EN (P<0.05). These results indicate that EN can lead to significant bacterial overgrowth on upper gastrointestinal tract mucosae and a significantly diminished pro-inflammatory cytokine response.

Potential hazards of excluded bowel and use of parenteral nutrition : A case report

This case demonstrates that excluded gut may be a reservoir for bacterial translocation and recurrent sepsis. Translocation may contribute to cholestatic hepatitis, and restoration of bowel continuity is fundamental to reversing these pathologic changes. It also emphasizes that parenteral nutrition even when used as interim supportive treatment is not without serious hazard.