Nutrient intakes in adult and pediatric coeliac disease patients on gluten-free diet: a systematic review and meta-analysis.

Celiac Disease (CD) continues to require a strict lifetime gluten-free diet (GFD) to maintain healthy status. Many studies have assessed the GFD nutritional adequacy in their cohorts, but an overall picture in adults and children would offer a lifetime vision to identify actionable areas of change. We aimed at assessing the nutrient intakes of adult and pediatric CD patients following a GFD diet and identifying potential areas of improvement. Systematic review was carried out across PubMed, Scopus and Scholar up to October 2022, including full-text studies that assessed the nutrient intakes of CD patients on GFD, in terms of macro- and/or micronutrients (absolute or percentage daily average). Random-effect meta-analysis and univariable meta-regression were applied to obtain pooled estimates for proportions and influencing variables on the outcome, respectively. Thirty-eight studies with a total of 2114 patients were included. Overall, the daily energy intake was 1995 (CI 1884-2106) Kcal with 47.8% (CI 45.7-49.8%) from carbohydrates, 15.5% (CI 14.8-16.2%) from proteins, and 35.8% (CI 34.5-37.0%) from fats. Of total fats, 13.2% (CI 12.4-14.0%) were saturated fats. Teenagers had the highest consumption of fats (94.9, CI 54.8-134.9 g/day), and adults presented insufficient dietary fiber intake (18.9 g, CI 16.5-21.4 g). Calcium, magnesium, and iron intakes were particularly insufficient in adolescence, whereas vitamin D was insufficient in all age groups. In conclusion, GFD may expose CD patients to high fat and low essential micronutrient intakes. Given GFD is a lifelong therapy, to prevent the occurrence of diseases (e.g. cardiovascular or bone disorders) dietary intakes need to be assessed on long-term follow-ups.

Levofloxacin prophylaxis and parenteral nutrition have a detrimental effect on intestinal microbial networks in pediatric patients undergoing HSCT.

The gut microbiome (GM) has shown to influence hematopoietic stem cell transplantation (HSCT) outcome. Evidence on levofloxacin (LVX) prophylaxis usefulness before HSCT in pediatric patients is controversial and its impact on GM is poorly characterized. Post-HSCT parenteral nutrition (PN) is oftentimes the first-line nutritional support in the neutropenic phase, despite the emerging benefits of enteral nutrition (EN). In this exploratory work, we used a global-to-local networking approach to obtain a high-resolution longitudinal characterization of the GM in 30 pediatric HSCT patients receiving PN combined with LVX prophylaxis or PN alone or EN alone. By evaluating the network topology, we found that PN, especially preceded by LVX prophylaxis, resulted in a detrimental effect over the GM, with low modularity, poor cohesion, a shift in keystone species and the emergence of modules comprising several pathobionts, such as Klebsiella spp., [Ruminococcus] gnavus, Flavonifractor plautii and Enterococcus faecium. Our pilot findings on LVX prophylaxis and PN-related disruption of GM networks should be considered in patient management, to possibly facilitate prompt recovery/maintenance of a healthy and well-wired GM. However, the impact of LVX prophylaxis and nutritional support on short- to long-term post-HSCT clinical outcomes has yet to be elucidated.

The PURPLE N study: objective and perceived nutritional status in children and adolescents with cerebral palsy.

PURPOSE: To obtain information on characteristics, management, current objective nutritional status and perception of nutritional status of children with cerebral palsy (CP) from healthcare professionals (HCPs) and caregivers. MATERIALS AND METHODS: A detailed survey of several items on eight main topics (general characteristics, motor function, comorbidities, therapies, anthropometry, feeding mode and problems and perceived nutritional status) was developed and tested for the study. Correlation between nutritional status and Gross Motor Function Classification System (GMFCS) levels was assessed using continuous variables (Z-scores for weight-for-age, height-for-age, weight-for-height, and body mass index-for-age), and categorical variables (being malnourished, stunted, or wasted). HCP and caregiver perceptions of the child's nutritional status as well as agreement between perceived and objective nutritional status and agreement between perceived nutritional status and concerns about the nutritional status were analyzed. RESULTS: Data were available for 497 participants from eight European countries. Poorer nutritional status was associated with higher (more severe) GMFCS levels. There was minimal agreement between perceived and objective nutritional status, both for HCPs and caregivers. Agreement between HCP and caregiver perceptions of the child's nutritional status was weak (weighted kappa 0.56). However, the concerns about the nutritional status of the child were in line with the perceived nutritional status. CONCLUSIONS: The risk of poor nutritional status is associated with more severe disability in children and adolescents with CP. There is a mismatch between HCP and caregiver perceptions of participants' nutritional status as well as between subjective and objective nutritional status. Our data warrant the use of a simple and objective screening tool in daily practice to determine nutritional status in children and adolescents with CP. Clinical trial registration: ClinicalTrials.gov Identifier: NCT03499288 (https://clinicaltrials.gov/ct2/show/NCT03499288). IMPLICATIONS FOR REHABILITATIONUse of the ESPGHAN recommendations and simple screening tools in daily practice is needed to improve nutritional care for individuals with CP.Attention should be paid to the differences in the perception of nutritional status of individuals with CP between professionals and caregivers to improve appropriate referral for nutritional support.Objective measures rather than the professional's perception need to be used to define the nutritional status of individuals with CP.

Eating and Lifestyle Habits in Youth With Down Syndrome Attending a Care Program: An Exploratory Lesson for Future Improvements.

Introduction: Children with Down Syndrome (DS) have nutritional problems with unknown implications besides increased potential for obesity. Their food habits are unknown. We aim to delineate eating and lifestyle habits of DS children attending a multispecialist program to identify the challenges they face and the potential improvements. Patients and Methods: We interacted with 34 DS children (22 males, 12 females, 2-16 years old) and their families. Food habits, medical conditions and treatments, degrees of development and physical activity, anthropometric and laboratory data were recorded over 6 months and analyzed. A 3-day food diary and a 24-h recall food frequency questionnaire were administered. Results: Twenty-nine (85%) children completed meals, only 11 (32%) received alternative food such as milk. Weaning regularly started in 25 (73%) children. Preschool children introduced adequate calories and nutrients. School children and adolescents did not reach recommendations. All age groups, as the general pediatric population, excessively ate protein and saturated fat, and preferred bread, pasta, fruit juices, meat and cold cuts. Peculiarly, pulses and fish were adequately assumed by preschool and school children, respectively. Five children (15%) were overweight/obese. Conclusions: Dietary excesses commonly found in the general pediatric population are also present in this DS group, proving a narrowing gap between the two. DS group performed better nutritionally in the early years and overweight/obesity occurrence seems contained. DS children may benefit from a practical yet professional care-program in which nutrition education may improve their growth, development and transition into adulthood.

Sugar Intake: Are All Children Made of Sugar?

INTRODUCTION: A healthy diet is characterized by a variety of food and a balanced energy intake, which should accompany every human being since early childhood. Unfortunately, excessive consumption of protein, fat, and lately sugar are very common in developed countries. Sugar intakes are not easily quantifiable and comparable among subjects. Therefore, we decide to analyze dietary patterns in children of different ages and diets (with and without gluten) using a food and nutrient database and a new application called the "Zuccherometro". PATIENTS AND METHODS: This is a descriptive observational study conducted among children that are recruited consecutively either during a pediatric evaluation or through a school survey. Sociodemographic, nutritional and anthropometric data, degree of physical activity, and presence of medical conditions are collected. Dietary intake data are obtained by a 24 h recall diet. RESULTS: The study analyzes 400 children: 213 girls and 187 boys. The majority of children (70.7%) are in normal weight range with similar extreme values (6.5% obese and 6.7% underweight). Celiac disease is diagnosed in 186 children. Caloric intakes are in line with the recommendations in all age-distributed groups with the exception of adolescents (11-17 years old), whose caloric intake is lower than recommendations. Protein intakes, on the contrary, are always exceeding recommendations and are significantly elevated in preschool children, (more than three times the population reference intakes). As for sugar intakes, all the children except the 11-17 years adolescents exceed the recommended cut off of 15% of daily calories. The same trend is obtained using the "Zuccherometro" that shows different percentages of age-stratified children exceeding the reference values: 1-3 years, 59% of children; 4-6 years, 68%; 7-10 years, 39.8%; 11-14 years, 25.5%; 15-17 years, 24.5%. The sugar load consists of both natural or added sugars (fructose and lactose) in food or beverages. Sugar intakes are more generously consumed by all age-stratified controls than by celiac children with the exception of the youngest ones (1-3 years old) and male adolescents. CONCLUSION: Since high sugar intakes are constantly accompanying children during their growth, important dietary education and coordination between families and institutions are mandatory.

Enteral nutrition protects children undergoing allogeneic hematopoietic stem cell transplantation from blood stream infections.

Enteral Nutrition (EN) is recommended as first line nutritional support for patients undergoing Allogeneic Hematopoietic Stem Cell Transplantation (allo-HSCT), but only few studies exist in the literature which compare EN to Parenteral Nutrition (PN) in the paediatric population.Forty-two consecutive paediatric patients undergoing allo-HSCT at our referral centre between January 2016 and July 2019 were evaluated. Post-transplant and nutritional outcomes of patients receiving EN for more than 7 days (EN group, n = 14) were compared with those of patients receiving EN for fewer than 7 days or receiving only PN (PN group, n = 28). In the EN group, a reduced incidence of Blood Stream Infections (BSI) was observed (p = 0.02) (n = 2 vs. n = 15; 14.3% vs. 53.6%). The type of nutritional support was also the only variable independently associated with BSI in the multivariate analysis (p = 0.03). Platelet engraftment was shorter in the PN group than in the EN group for a threshold of > 20*109/L (p = 0.04) (23.1 vs 35.7 days), but this correlation was not confirmed with a threshold of > 50*109/L. The Body Mass Index (BMI) and the BMI Z-score were no different in the two groups from admission to discharge.Our results highlight that EN is a feasible and nutritionally adequate method of nutritional support for children undergoing allo-HSCT in line with the present literature. Future functional studies are needed to better address the hypothesis that greater intestinal eubyosis maintained with EN may explain the observed reduction in BSI.

Gluten Deprivation: What Nutritional Changes Are Found During the First Year in Newly Diagnosed Coeliac Children?

AIM: A gluten-free diet (GFD) can expose children to excessive calories and fat intake. The study is intended to verify whether and how food intake, laboratory parameters, and growth are modified by a year of GFD. METHODS: In 79 CD (coeliac disease) children (mean age 7.9 ± 3.8 years, 52 females, 27 males) diagnosed over 24 months, 24-h food diaries, food-frequency patterns, anthropometric and laboratory parameters (mainly blood sugar, insulin, lipid profile, and homocysteine) were prospectively collected before and during the first year of GFD. Nutrient intakes were compared over time and with recommendations. They were also used as regressors to explain the levels and changes of metabolic and growth variables. p-values < 0.05 were considered statistically significant. RESULTS: Average macronutrient intake did not change during the year. Caloric intake remained below 90% (p ≤ 0.0001) and protein intake above 200% (p ≤ 0.0001) of recommendations. Lipid intake was stable at 34% of overall energy intake. Unsaturated fats increased (less omega-6 and more omega-3 with a ratio improvement from 13.3 ± 5.5 to 8.8 ± 3.1) and so did fibers, while folate decreased. The children who experienced a containment in their caloric intake during the year, presented a slower catch-up growth. Some differences were found across gender and age groups. In particular, adolescents consumed less calories, and females more omega-3. Fiber and simple sugar intakes emerged as implicated in lipid profile shift: fibers negatively with triglycerides (TG) (p = 0.033), simple sugars negatively with high-density lipoprotein (HDL) (p = 0.056) and positively with TG (p = 0.004). Waist-to-height ratio was positively associated with homocysteine (p = 0.018) and Homeostasis Model Assessment (p = 0.001), negatively with fibers (p = 0.004). CONCLUSION: In the short run, GFD is nutritionally very similar to any diet with gluten, with some improvements in unsaturated fats and fiber intake. Along with simple sugars containment, this may offer CD patients the opportunity for a fresh start. Caloric intakes may shift and should be monitored, especially in adolescents.

An internet-based approach for lifestyle changes in patients with NAFLD: Two-year effects on weight loss and surrogate markers.

BACKGROUND & AIMS: Interventions aimed at lifestyle changes are pivotal for the treatment of non-alcoholic fatty liver disease (NAFLD), and web-based programs might help remove barriers in both patients and therapists. METHODS: In the period 2010-15, 716 consecutive NAFLD cases (mean age, 52; type 2 diabetes, 33%) were treated in our Department with structured programs. The usual protocol included motivational interviewing and a group-based intervention (GBI), chaired by physicians, dietitians and psychologists (five weekly meetings, n = 438). Individuals who could not attend GBI entered a web-based intervention (WBI, n = 278) derived from GBI, with interactive games, learning tests, motivational tests, and mail contacts with the center. The primary outcome was weight loss ≥10%; secondary outcomes were alanine aminotransferase within normal limits, changes in lifestyle, weight, alanine aminotransferase, and surrogate markers of steatosis and fibrosis. RESULTS: GBI and WBI cohorts had similar body mass index (mean, 33 kg/m2), with more males (67% vs. 45%), younger age, higher education, and more physical activity in the WBI group. The two-year attrition rate was higher in the WBI group. Healthy lifestyle changes were observed in both groups and body mass index decreased by almost two points;the 10% weight target was reached in 20% of WBI cases vs. 15% in GBI (not significant). In logistic regression analysis, after adjustment for confounders and attrition rates, WBI was not associated with a reduction of patients reaching short- and long-term 10% weight targets. Liver enzymes decreased in both groups, and normalized more frequently in WBI. Fatty liver index was reduced, whereas fibrosis remained stable (NAFLD fibrosis score) or similarly decreased (Fib-4). CONCLUSION: WBI is not less effective than common lifestyle programs, as measured by significant clinical outcomes associated with improved histological outcomes in NAFLD. eHealth programs may effectively contribute to NAFLD control. LAY SUMMARY: In patients with non-alcoholic fatty liver disease, participation in structured lifestyle programs may be jeopardized by job and time constraints. A web-based intervention may be better suited for young, busy patients, and for those living far from liver units. The study shows that, following a structured motivational approach, a web-based, interactive intervention coupled with six-month face-to-face meetings is not inferior to a standard group-based intervention with respect to weight loss, adherence to healthy diet and habitual physical activity, normalization of liver enzymes, and stable surrogate markers of fibrosis.

Paediatric Home Artificial Nutrition in Italy: Report from 2016 Survey on Behalf of Artificial Nutrition Network of Italian Society for Gastroenterology, Hepatology and Nutrition (SIGENP).

Home Artificial Nutrition (HAN) is a safe and efficacious technique that insures children's reintegration into the family, society and school. Epidemiological data on paediatric HAN in Italy are not available. AIM: to detect the prevalence and incidence of Home Parenteral Nutrition (HPN) and Home Enteral Nutrition (HEN), either via tube or mouth, in Italy in 2016. MATERIALS AND METHODS: a specific form was sent to all registered SIGENP members and investigators of local HAN centres, inviting them to provide the requested centre's data and demographics, underlying diseases and HAN characteristics of the patients. RESULTS: we recorded 3403 Italian patients on HAN aged 0 to 19 years from 22 centres: 2277 HEN, 950 Oral Nutritional Supplements (ONS) and 179 HPN programs. The prevalence of HEN (205 pts/million inhabitants) and HPN (16 pts/million inhabitants) has dramatically increased in Italy in the last 9 years. Neurodisabling conditions were the first indication for HEN by tube or mouth while HPN is mainly requested in digestive disorders. CONCLUSIONS: HAN is a widespread and rapidly growing treatment in Italy, as well as in other European countries. Awareness of its extent and characteristics helps improving HAN service and patients' quality of life.

Insulin Instability in Parenteral Nutrition Admixtures.

BACKGROUND: Biosynthetic human recombinant short-acting insulin is added to parenteral nutrition (PN) admixtures to nourish glucose-intolerant patients. Insulin, however, is electrostatically attracted and inactivated by ethyl-vinyl-acetate (EVA) bags and filling system tubes. Our aim was to verify and quantify the presence of insulin in PN with and without intravenous lipid emulsion (ILE), just after addition (T0) until the infusion's end (T24). METHODS: Four undiluted samples of 12 different PN complete admixtures (6 with ILE and 6 without), each containing 250 g of glucose in a 2000 mL volume, were taken and analyzed at T0 and T24 by an automated electrochemiluminescence immunoassay after the addition of biosynthetic human recombinant short-acting insulin at increasing doses (from 6 to 72 IU/bag) by an automated compounding device. Assay sensitivity was set at 2 µIU/mL. Admixtures with and without ILE were compared in terms of insulin-detected amounts at T0 and T24. RESULTS: Regardless of the amount initially provided, insulin was missing in PN without ILE. In admixtures with ILE, the greater the insulin and ILE doses initially included, the higher the insulin availability at T0 and T24, both in absolute terms and as a percentage of the initial amount (from 3 to 81% at T0 and from 2.5 to 72.5% at T24). ILE may prevent insulin attraction to plastic surfaces. CONCLUSIONS: Insulin is recovered in the presence of ILE in PN even though considerable amounts are untraceable. This aspect needs verification. Until then, insulin should safely be injected in a different manner in uncontrolled situations.

Phytonadione Content in Branded Intravenous Fat Emulsions.

BACKGROUND: Intravenous fat emulsions (IVFE) with different fatty acid compositions contain vitamin E as a by-product of vegetable and animal oil during the refining processes. Likewise, other lipid-soluble vitamins may be present in IVFE. No data, however, exist about phytonadione (vitamin K1) concentration in IVFE information leaflets. Therefore, our aim was to evaluate the phytonadione content in different IVFE. MATERIALS AND METHODS: Analyses were carried out in triplicate on 6 branded IVFE as follows: 30% soybean oil (100%), 20% olive-soybean oil (80%-20%), 20% soybean-medium-chain triglycerides (MCT) coconut oil (50%-50%), 20% soybean-olive-MCT-fish oil (30%-25%-30%-15%), 20% soybean-MCT-fish oil (40%-50%-10%), and 10% pure fish oil (100%). Phytonadione was analyzed and quantified by a quali-quantitative liquid chromatography-mass spectrometry (LC-MS) method after its extraction from the IVFE by an isopropyl alcohol-hexane mixture, reverse phase-liquid chromatography, and specific multiple-reaction monitoring for phytonadione and vitamin d3 (as internal standard). This method was validated through specificity, linearity, and accuracy. RESULTS: Average vitamin K1 content was 500, 100, 90, 100, 95, and 70 µg/L in soybean oil, olive-soybean oil, soybean-MCT coconut oil, soybean-olive-MCT-fish oil, soybean-MCT-fish oil, and pure fish oil intravenous lipid emulsions (ILEs), respectively. The analytical LC-MS method was extremely effective in terms of specificity, linearity ( r = 0.99), and accuracy (coefficient of variation <5%). CONCLUSIONS: Phytonadione is present in IVFE, and its intake varies according to IVFE type and the volume administered. It can contribute to daily requirements and become clinically relevant when simultaneously infused with multivitamins during long-term parenteral nutrition. LC-MS seems adequate in assessing vitamin K1 intake in IVFE.

Potential intake of vitamins "A" and "D" through branded intravenous lipid emulsions: Liquid Chromatography-Tandem Mass Spectrometry Analysis.

No data exist for vitamin A group and vitamin D2/D3 content in branded intravenous lipid emulsions (ILEs). Our goal is to evaluate and quantify their concentrations in different ILEs to assess whether they are clinically relevant. Analyses were carried out in triplicates on six ILEs: 1) 30% soybean oil-based, 2) 20% olive-soybean oil based, 3) 10 + 10% soybean - MCT coconut oil based, 4) 20% soybean-olive-MCT-fish oil based, 5) 20% soybean-MCT-fish oil based and 6) 10% pure fish oil based, respectively. Retinol group (vitamin A) and ergo-chole-calciferol (vitamin D2/D3) were analyzed and quantified by a quali-quantitative Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) method after potassium hydroxide alkaline hydrolysis, hexane extraction, reverse phase-liquid chromatography and specific multiple-reaction-monitoring (MRM) detection. On average, measured retinol content was in the range of 200-1000 µg/L in ILEs (1,2, and 3), whereas it was higher (1000-2000 µg/L) in the ILEs containing fish-oil. Vitamin D content was in the range of 1-10 µg/L in the fish-oil based ILEs, but undetectable in those ILEs containing purely vegetable oils. This study shows that vitamin A and D contents are variably present in ILEs based on their different lipid sources. Both contents should be explicitly mentioned in the products.

A New Formulation of an Old Drug: A Potential New Therapy in the Management of Oral cGvHD.

Oral chronic graft versus host disease (cGVHD) is often refractory to systemic therapies. Additional topical treatment is commonly required. The potency of the agent, the vehicle and formulation in which it is delivered are all critical factors in determining the effectiveness of topical therapies. High potency of budesonide, combined with its very low bioavailability when absorbed through mucosal surfaces, increased the potential role in topical application for oral cGVHD. Viscous formulation increases mucosal contact time resulting in a greater decrease in mucosal inflammation. This short communication suggests that oral viscous budesonide should be considered as a potential new therapy in the management of oral cGVHD.

The spectrum of plant and animal sterols in different oil-derived intravenous emulsions.

Intravenous lipid constituents have different effects on various biological processes. Some of these effects are protective, while others are potentially adverse. Phytosterols, in particular, seem to be implicated with parenteral nutrition-associated cholestasis. The aim of this study is to determine the amount of plant and animal sterols present in lipid formulations derived from different oil sources. To this end, animal (cholesterol) and plant (beta-sitosterol, campesterol, and stigmasterol) sterols in seven different commercially available intravenous lipid emulsions (ILEs) were quantified by capillary gas chromatography after performing a lipid extraction procedure. The two major constituents of the lipid emulsions were cholesterol (range 14-57% of total lipids) and beta-sitosterol (range 24-55%), followed by campesterol (range 8-18%) and stigmasterol (range 5-16%). The fish oil-derived formulation was an exception, as it contained only cholesterol. The mean values of the different sterols were statistically different across ILEs (P = 0.0000). A large percentage of pairwise comparisons were also statistically significant (P = 0.000), most notably for cholesterol and stigmasterol (14 out of 21 for both), followed by campesterol (12 out 21) and beta-sitosterol (11 out 21). In conclusion, most ILEs combined significant amounts of phytosterols and cholesterol. However, their phytosterols:cholesterol ratios were reversed compared to the normal human diet.

Better living through chemistry, constant monitoring, and prompt interventions: 26 years on home parenteral nutrition without major complications.

OBJECTIVE: We discuss 26 y of home parenteral nutrition (HPN) in an otherwise healthy patient with severe short bowel syndrome demonstrating a decrease in life-threatening complications after various management changes. METHODS: The patient is a 41-y-old male with a midgut volvulus from malrotation who developed short bowel syndrome and has been HPN dependent since the age of 15 y. His surgical and nutritional data were collected retrospectively and prospectively and included nutritional history, anthropometric parameters, laboratory results, activity levels and types, and treatments for complications. His entire HPN course has been prospectively followed. RESULTS: Since becoming HPN dependent, the patient's energy intake range has been 20-45 kcal.kg(-1).d(-1), with 0.8-1.6 g of protein.kg(-1).d(-1). He receives HPN with electrolytes, multivitamins, and trace elements nightly and his intravenous fat emulsion ranges from one to seven times per week. Adjustments to magnesium, iron, zinc, selenium, vitamin E, and carnitine are often required. During his first years of HPN, he had six episodes of catheter-related sepsis and two central venous catheter occlusions. The current central venous catheter has been in place for >13 y without infection or replacement. He developed mild osteopenia but has maintained an active lifestyle without fractures. In the second and third decades of HPN, episodes of hepatic dysfunction occurred, with improvement or resolution using various interventions including oral fish oil. CONCLUSION: This case illustrates the successful management of a life-long HPN-dependent patient in whom PN complications have been minimized, including a very recent occurrence of parenteral nutrition-associated cholestasis.

The role of gut-associated lymphoid tissues and mucosal defence.

The newborn infant leaves a germ-free intrauterine environment to enter a contaminated extrauterine world and must have adequate intestinal defences to prevent the expression of clinical gastrointestinal disease states. Although the intestinal mucosal immune system is fully developed after a full-term birth, the actual protective function of the gut requires the microbial stimulation of initial bacterial colonization. Breast milk contains prebiotic oligosaccharides, like inulin-type fructans, which are not digested in the small intestine but enter the colon as intact large carbohydrates that are then fermented by the resident bacteria to produce SCFA. The nature of this fermentation and the consequent pH of the intestinal contents dictate proliferation of specific resident bacteria. For example, breast milk-fed infants with prebiotics present in breast milk produce an increased proliferation of bifidobacteria and lactobacilli (probiotics), whereas formula-fed infants produce more enterococci and enterobacteria. Probiotics, stimulated by prebiotic fermentation, are important to the development and sustainment of intestinal defences. For example, probiotics can stimulate the synthesis and secretion of polymeric IgA, the antibody that coats and protects mucosal surfaces against harmful bacterial invasion. In addition, appropriate colonization with probiotics helps to produce a balanced T helper cell response (Th1=Th2=Th3/Tr1) and prevent an imbalance (Th1>Th2 or Th2>Th1) contributing in part to clinical disease (Th2 imbalance contributes to atopic disease and Th1 imbalance contributes to Crohn's disease and Helicobacter pylori-induced gastritis). Furthermore, a series of pattern recognition receptors, toll-like receptors on gut lymphoid and epithelial cells that interact with bacterial molecular patterns (e.g. endotoxin (lipopolysaccharide), flagellin, etc.), help modulate intestinal innate immunity and an appropriate adaptive immune response. Animal and clinical studies have shown that inulin-type fructans will stimulate an increase in probiotics (commensal bacteria) and these bacteria have been shown to modulate the development and persistence of appropriate mucosal immune responses. However, additional studies are needed to show that prebiotics can directly or indirectly stimulate intestinal host defences. If this can be demonstrated, then prebiotics can be used as a dietary supplement to stimulate a balanced and an appropriately effective mucosal immune system in newborns and infants.

Nutritional factors contributing to the development of cholestasis during total parenteral nutrition.

Parenteral nutrition-associated cholestasis is a major clinical problem in pediatrics, particularly during infancy in children with short bowel syndrome who require long-term use of total parenteral nutrition (TPN) for survival. Multifactorial theories regarding the origin of parenteral nutrition-associated cholestasis have not yet defined its pathogenesis or resulted in a solution to the problem. However, our knowledge of risk factors has helped develop new hypotheses as to the mechanisms of this disease. In this review, we consider the following potential risk factors that influence the development of this condition: (1) the gastrointestinal dysfunction associated with the absence of enteric nutrients while receiving TPN; (2) components of TPN solutions as potential hepatotoxins; and (3) the contribution of the underlying disease necessitating TPN for adequate nutrition. It is hoped that a better understanding of factors affecting hepatocyte secretion and bile formation and flow will help to prevent this life-threatening complication of TPN.