Andrew R. Barclay

Probiotics for necrotizing enterocolitis : A systematic review

Background: Necrotizing enterocolitis (NEC) is the most commonly acquired neonatal intraabdominal emergency and causes significant morbidity and mortality. A proposed strategy for the prevention of NEC is the administration of oral probiotics. Probiotics have been shown to reduce NEC in experimental rat models and have been used in clinical trials. The authors aimed to review the existing data on the use of oral probiotics for the prevention of NEC in preterm infants (age <33 weeks) and those with very low birth weight (VLBW). Materials and Methods: Systematic review of randomized controlled trials (RCTs) and quasi-RCTs was performed to find outcome measures of incidence, severity, need for surgery, and mortality in NEC. Electronic searches were performed on Medline and CINAHL databases using key word and subject headings with combinations of the terms “infant, preterm”; “infant, VLBW”; “enterocolitis, necrotizing”; and “probiotics.” In addition, citation searches were performed for all potential studies. Results: Six potential RCTs were identified for inclusion, but there were no systematic or Cochrane database reviews identified. One study was discounted because of the use of historical controls, so 5 studies were selected for analysis. Cumulatively, 640 infants were treated with probiotics and 627 were used as control subjects. All of the studies showed a trend toward less NEC in the treatment group. The heterogeneity of probiotic formulations and the timing and methods of interventions in the identified studies made synthesis and comparison of data inappropriate. Conclusions: The data appear to lend support to the use of oral probiotics for the prevention of NEC in preterm infants and those with VLBW. However, the data are insufficient to comment on their short- and long-term safety. Type of probiotics used, as well as the timing and dosage, are still to be optimized. Further understanding of the pathogenesis of NEC and the mechanisms by which probiotics prevent it may lead to evidence-based treatment strategies.

Systematic review: medical and nutritional interventions for the management of intestinal failure and its resultant complications in children

Aliment Pharmacol Ther 2011; 33: 175–184

Cerebral thromboembolic events in pediatric patients with inflammatory bowel disease

Background: There is a recognized association between pediatric inflammatory bowel disease (IBD) and cerebral thromboembolic events (CTEs). Historical reporting had described the association as strongest between ulcerative colitis (UC), rather than Crohns disease (CD). We describe the incidence and outcome of CTE in pediatric IBD patients from a single center over 5 years and the relative proportion of stroke reported in the literature in patients with UC and CD before and after January 2000. Methods: Demographic data were extracted on all newly diagnosed cases of IBD in our center from January 2003 to January 2008 to ascertain patient characteristics, disease type, risk factors for CTE, modality of neuroimaging, and outcome. A literature search was performed to identify all articles describing stroke in pediatric IBD. All identified studies were stratified into those published before and after January 1 2000. Results: In all, 154 new patients diagnosed with IBD (male 56%) (UC 30%, CD 64%, IBD unclassified [IBDU] 6%) were reviewed. Four cases of CTE occurred in our population over 5 years (2.6%). All patients had a risk factor for CTE. Fifteen case series were identified with 32 patients. There was a significant increase in the proportion strokes affecting patients with CD reported after January 2000 (P = 0.02). Conclusions: CTE affects a proportion of pediatric IBD patients. Although resolution of physical impairment is the norm, significant morbidity exists. Our study suggests a secular trend toward CTE in CD. Primary prevention with the identification and amelioration of identifiable risk factors should be the clinical objective in future studies. (Inflamm Bowel Dis 2009)

Use of Stable Isotopes To Measure the Metabolic Activity of the Human Intestinal Microbiota

ABSTRACT The human intestinal microbiota is a complex biological system comprising a vast repertoire of microbes with considerable metabolic activity relevant to both bacterial growth and host health. Greater strides have been made in the analysis of microbial diversity than in the measurement of functional activity, particularly in vivo. Stable isotope probing offers a new approach by coupling measurements of metabolic activity with microbial identification. Using a low-enrichment labeling strategy in vitro, this study has identified metabolically active bacterial groups via magnetic-bead capture methodology and stable isotope ratio analysis. Using five probes (EUB338, Bac303, Bif164, EREC482, and Clep866), changes in the activities of key intestinal microbial groups were successfully measured by exploiting tracers of de novo RNA synthesis. Perturbation of the nutrient source with oligofructose generated changes in the activity of bifidobacteria as expected, but also in the Bacteroides-Prevotella group, the Eubacterium rectale-Clostridium coccoides group, and the Clostridium leptum subgroup. Changes in activity were also observed in response to the medium type. This study suggests that changes in the functional activity of the gut microbiota can be assessed using tracers of de novo nucleic acid synthesis combined with measurement of low isotopic enrichment in 16S rRNA. Such tracers potentially limit substrate bias because they are universally available to bacteria. This low-enrichment labeling approach does not depend on the commercial availability of specific labeled substrates and can be easily translated to in vivo probing experiments of the functional activity of the microbiota in the human gut.

Regionally acquired intestinal failure data suggest an underestimate in national service requirements

Objectives, setting and patients: With complete case referral for prolonged parenteral nutrition (PN) beyond term equivalent, serving a stable population of 1.25 million people, we describe the long-term outcome and survival of patients referred to an intestinal failure (IF) nutrition support team over the first 8 years of existence at a regional paediatric centre, and extrapolate to potential numbers of national home parenteral nutrition (HPN) cases and intestinal transplantation data. Design and outcome measures: Retrospective analysis detailing patient demographics, interventions, use of HPN, occurrence of intestinal failure-associated liver disease (IFALD), and outcomes of enteral adaptation, survival, and referral for and receipt of organ transplantation. Results: 23 patients were referred over 8 years, 20 being PN dependent within the neonatal period. Diagnoses included short bowel syndrome (SBS) (18), neuromuscular abnormalities (4) and congenital enterocyte disorder (1). 12 696 days of PN were delivered with 314 confirmed episodes of sepsis at a median of 12 episodes per patient. 144 central venous catheters (CVCs) were required at a median of four per patient. IFALD occurred in 17 (73%) patients, with 10 (44%) referred for transplant assessment. Thirteen (56%) children received HPN. Overall mortality was 44%. A significant predictor for survival in the SBS group was residual bowel >40 cm (82% vs 28%, p = 0.049). Conclusions: Survival for IF at 56% was lower than reported from non-UK supra-regional centres, and nationally collected data, possibly reflecting pre-selected referral populations. Data from regional centres with complete ascertainment may be important both when counselling parents and when planning regional and national HPN and IF specialist services.

Cycled enteral antibiotics reduce sepsis rates in paediatric patients on long‐term parenteral nutrition for intestinal failure

Aliment Pharmacol Ther 2011; 34: 1005–1011

Successful implementation of a nurse-led teaching programme to independently administer subcutaneous methotrexate in the community setting to children with Crohn's disease.

Background  Methotrexate is increasingly used as a third line immunosuppression agent in children with Crohn’s disease (CD). Methotrexate is traditionally administered in the hospital setting.

Mo1984 Stool Secretory IgA Levels in Preterm Infants With and Without Necrotising Enterocolitis

Introduction Secretory Immunoglobulin A (SIgA) is the most prolific immunoglobulin of the GI tract, and high levels in preterm infants may prevent necrotising enterocolitis, the most devastating disease of the gut of early life. Our aim was to determine and compare the levels of SIgA in stool samples of preterm neonates and breast milk in their mothers. Design The NAPI Study (see abstract 1299049) sequentially recruited infants 0.05) within all the four weeks. A significant increase in mean stool sIgA concentration appeared from week 2 to week 3 (p=0.0485) in NEC infants and from week 1 to week 2 (p=0.005) for those without NEC. For all breastfed preterm neonates (n=6) in the first four weeks, the level of milk sIgA was significant higher on week 1 (colostrum) than week 2 (p=0.021) and week 3 (p=0.034). Conclusions Our study illustrates immunological adaptation of maternal milk sIgA level for the preterm newborn and that exclusive breast milk feeding may increase stool sIgA more than mixed breast milk and formula. Levels found in stool and milk are significantly higher than for infants and mothers at term.