Weaning to hypoallergenic formula improves gut barrier function in breast-fed infants with atopic eczema

Does a Little Difference Make a Big Difference? Bovine β-Casein A1 and A2 Variants and Human Health-An Update

For over 20 years, bovine beta-casein has been a subject of increasing scientific interest because its genetic A1 variant during gastrointestinal digestion releases opioid-like peptide β-casomorphin-7 (β-CM-7). Since β-CM-7 is involved in the dysregulation of many physiological processes, there is a growing discussion of whether the consumption of the β-casein A1 variant has an influence on human health. In the last decade, the number of papers dealing with this problem has substantially increased. The newest clinical studies on humans showed a negative effect of variant A1 on serum glutathione level, digestive well-being, cognitive performance score in children, and mood score in women. Scientific reports in this field can affect the policies of dairy cattle breeders and the milk industry, leading to the elimination of allele A1 in dairy cattle populations and promoting milk products based on milk from cows with the A2A2 genotype. More scientific proof, especially in well-designed clinical studies, is necessary to determine whether a little difference in the β-casein amino acid sequence negatively affects the health of milk consumers.

Short article: The endoscopic and histologic findings of infants who have experienced brief resolved unexplained events

INTRODUCTION

A brief resolved unexplained event (BRUE) describes an event associated with a change in muscle tone, color, respiration, and responsiveness that is unexplained after an appropriate examination. Some infants with higher risk BRUE may undergo endoscopy as part of their evaluation.

OBJECTIVE

This retrospective study aimed to identify the endoscopic findings in infants who have experienced a higher risk BRUE. We also compared the characteristics, prenatal, natal, and postnatal risk factors between 23 infants who underwent endoscopic evaluation and 23 race-matched/sex-matched/term-matched/preterm-matched infants who did not undergo endoscopic evaluation.

METHODS

This was a retrospective descriptive study. Infants were identified from a query of medical records using the ICD-10 code for BRUE (R68.13).

RESULTS

Of 119 infants with BRUE, 23 infants with higher risk BRUE underwent an esophagogastroduodenoscopy and flexible sigmoidoscopy. Apnea (87%) was the most common presentation of BRUE. Most were female (57%) with a mean age at BRUE presentation of 2.73 months. We found 10 (43.5%) term infants and 13 (56.5%) preterm infants in our study. There were no significant differences in characteristics, prenatal, natal, and postnatal risk factors between the infants who underwent endoscopy and those who did not undergo endoscopy. The most common abnormal endoscopic finding was lymphonodular hyperplasia (LNH) associated with eosinophilia in the rectosigmoid colon. The proportion of females in the LNH group was significantly higher than the non-LNH group.

CONCLUSION

Rectosigmoid LNH and eosinophilia, which are associated with milk soy protein intolerance (MSPI), were the most common findings on endoscopic evaluation. Although there is no proof of causation between MSPI and BRUE, MSPI should be considered in the differential diagnosis for higher risk BRUE.

Evaluation of an Amino Acid-Based Formula in Infants Not Responding to Extensively Hydrolyzed Protein Formula

Nearly 2% to 3% of infants and children younger than 3 years have confirmed cow's milk protein allergy with multiple clinical presentations including atopic dermatitis (AD), diarrhea, and vomiting/spitting up. Although most infants with cow's milk protein allergy experience clinical improvement with the use of an extensively hydrolyzed (EH) formula, highly sensitive infants may require an amino acid-based formula. In this observational, prospective study, 30 infants (1-12 months of age) with a history of weight loss and persistent allergic manifestations while on an EH formula were provided an amino acid-based formula for 12 weeks. Mean weight gain (z score change) improved +0.43 ± 0.28 (mean ± standard deviation) after the 12-week feeding period. Improvement was observed for many allergic symptoms including significant decreases in AD severity (P = 0.02). These results indicate the new amino acid-based infant formula supported healthy weight gain and improvement in allergic manifestations in infants not responding to EH formulas.

Do infants with gastroschisis may have a high incidence of non-IgE-mediated cow's milk protein allergy?

BACKGROUND/PURPOSE

To determine the frequency and characteristics of suspected cow's milk protein allergy (CMPA) in infants with gastroschisis and response to change in milk.

METHODS

A retrospective cohort study of 111 consecutive infants with gastroschisis.

RESULTS

64 episodes suggesting non-IgE-mediated CMPA occurred in 50 infants (45 %) at a median age of 44 days (9-186) and during the primary admission in 38 %. At the time of the episode the infant feed was breast milk (BM, n = 24), term formula (TF, n = 20) or extensively hydrolysed formula (EHF, n = 6). The feed was changed to EHF (34), amino acid formula (AAF) (14) or BM with maternal CMP-free diet (2). Partial or complete resolution of symptoms occurred in all. There was histological evidence of an allergic reaction to CMP in all four infants in whom tissue was available. Recurrent episodes occurred in 13/50 infants (26 %), 10 of whom were receiving EHF. There were no recurrent episodes in infants being fed with AAF.

CONCLUSION

Features suggesting non-IgE-mediated CMPA appear common in infants with gastroschisis.

β-casomorphin-7 alters μ-opioid receptor and dipeptidyl peptidase IV genes expression in children with atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease with heterogeneous clinical phenotypes reflecting genetic predisposition and exposure to environmental factors. Reactions to food may play a significant role especially in young children. Milk proteins are particularly strong allergens and are additional source of bioactive peptides including β-casomorphin-7 (BCM7, Tyr-Pro-Phe-Pro-Gly-Pro-Ile). BCM7 exerts its influence on nervous, digestive, and immune functions via the μ-opioid receptor (MOR). Proline dipeptidyl peptidase IV (DPPIV; EC 3.4.14.5) appears to be the primary degrading enzyme of BCM7. Moreover, DPPIV is known to restrict activity of proinflammatory peptides. BCM7 is considered to modulate an immune response by affecting MOR and DPPIV genes expression. In this study, we determined the MOR and DPPIV genes expression in children diagnosed with a severe form of AD. 40 healthy children and 62 children diagnosed with severe AD (AD score ≥60) were included in the study. Peripheral blood mononuclear cells (PBMCs) from the studied subjects were incubated with the peptide extracts of raw and hydrolysed cow milk with defined β-casein genotypes (A1A1, A2A2 and A1A2) and MOR and DPPIV genes expression was determined with real-time PCR. Incubation PBMCs with peptide extracts from cow milk caused an increase of the MOR gene expression (p<0.05; p<0.001) in AD children with a simultaneous decrease in the DPPIV gene expression (p<0.001). The obtained results supplement the knowledge on the BCM7 participation in AD etiology and provide an important diagnostic tool.

Autism spectrum disorders

Autism spectrum disorders (ASDs) are collectively the most commonly diagnosed pediatric neurodevelopmental condition. ASDs include autism, pervasive developmental disorder-not otherwise specified (PDD-NOS), Rett syndrome and Asperger disorder. ASD is characterized by impaired communication and social interaction and may involve developmental delays and seizure disorders. Recent parent-reported diagnosis of ASD in the United States put it at higher levels (1:91) than previously thought, with its diagnosis in boys occurring 4 to 5 times more frequently than in girls (1:58).¹ CDC estimates are currently 1:110;¹ up from 1:150 in 2007.² Annual medical expenditures for those affected are generally four to six times greater than for those without ASD.¹ While twin studies demonstrate that genetics play a significant role in ASD, the impact of environment should not be underestimated, given the approximate 20-fold increase in incidence over the last 20 years.³

Monitoring immune modulation by nutrition in the general population: identifying and substantiating effects on human health

Optimal functioning of the immune system is crucial to human health, and nutrition is one of the major exogenous factors modulating different aspects of immune function. Currently, no single marker is available to predict the effect of a dietary intervention on different aspects of immune function. To provide further guidance on the assessment and interpretation of the modulation of immune functions due to nutrition in the general population, International Life Sciences Institute Europe commissioned a group of experts from academia, government and the food industry to prepare a guidance document. A draft of this paper was refined at a workshop involving additional experts. First, the expert group defined criteria to evaluate the usefulness of immune function markers. Over seventy-five markers were scored within the context of three distinct immune system functions: defence against pathogens; avoidance or mitigation of allergy; control of low-grade (metabolic) inflammation. The most useful markers were subsequently classified depending on whether they by themselves signify clinical relevance and/or involvement of immune function. Next, five theoretical scenarios were drafted describing potential changes in the values of markers compared with a relevant reference range. Finally, all elements were combined, providing a framework to aid the design and interpretation of studies assessing the effects of nutrition on immune function. This stepwise approach offers a clear rationale for selecting markers for future trials and provides a framework for the interpretation of outcomes. A similar stepwise approach may also be useful to rationalise the selection and interpretation of markers for other physiological processes critical to the maintenance of health and well-being.

'Gut health': a new objective in medicine?

'Gut health' is a term increasingly used in the medical literature and by the food industry. It covers multiple positive aspects of the gastrointestinal (GI) tract, such as the effective digestion and absorption of food, the absence of GI illness, normal and stable intestinal microbiota, effective immune status and a state of well-being. From a scientific point of view, however, it is still extremely unclear exactly what gut health is, how it can be defined and how it can be measured. The GI barrier adjacent to the GI microbiota appears to be the key to understanding the complex mechanisms that maintain gut health. Any impairment of the GI barrier can increase the risk of developing infectious, inflammatory and functional GI diseases, as well as extraintestinal diseases such as immune-mediated and metabolic disorders. Less clear, however, is whether GI discomfort in general can also be related to GI barrier functions. In any case, methods of assessing, improving and maintaining gut health-related GI functions are of major interest in preventive medicine.

Content of beta-casomorphins in milk of women with a history of allergy

The prevalence of food allergies increased over the past decade. Most symptoms of food allergy appear during the first 2 yr of life. The aim of this study was to determine the beta-casomorphin-5 and -7 (BCMs) in colostrum and milk of 12 breast-feeding women with a history and clinical manifestation of food allergy. The results were compared with the data obtained from a control group of healthy age-matched breast-feeding women. The level of BCM in women with food allergy was constant during lactation, whereas the highest level of opioid peptides was found in colostrums of healthy women with a subsequent rapid decrease in mature milk. These differences in BCMs profile between allergic and healthy breast-feeding women suggest that BCM content in the human milk may be an indicator of allergic conditions.

The role of food allergy in atopic dermatitis

Atopic dermatitis (AD) is a chronic, pruritic, inflammatory skin disease affecting more than 10% of all children. Sensitization to foods triggers isolated skin symptoms in about 30% of children. These symptoms include immediate reactions within minutes after ingesting food without exacerbation of AD and early and late exacerbations of AD. It is important to identify clinically relevant sensitizations to foods using skin prick tests, a specific IgE blood test (ImmunoCAP; Phadia, Portage, MI, USA), and double-blind, placebo-controlled food challenges to initiate appropriate dietary interventions and avoid unnecessary dietary restrictions. Children with AD triggered by food allergens demonstrate a distinct immune response upon stimulation of their peripheral blood mononuclear cells with food allergen. A defective skin barrier and increased intestinal permeability appear to facilitate allergen sensitization. Appropriate skin care to maintain skin barrier function and dietary avoidance of highly allergenic foods during infancy may help to prevent allergen sensitization, thereby reducing the severity of AD and food allergies.

The efficacy of amino acid-based formulas in relieving the symptoms of cow's milk allergy: a systematic review

The aim of this systematic review was to evaluate the efficacy of amino acid-based formulas (AAF) in patients with cow's milk allergy (CMA). Studies were identified using electronic databases and bibliography searches. Subjects eligible for inclusion were patients of any age with CMA or symptoms suggestive of it. Comparisons of interest were AAF vs. extensively hydrolysed formula (eHF), AAF vs. soy-based formula (SF) and AAF vs. cow's milk or cow's milk-based formula. Outcomes of interest were gastrointestinal (GI), dermatological, respiratory and behavioural symptoms as well as growth. A total of 20 studies [three head-to-head randomized controlled trials (RCTs), three cross-over challenge RCTs, seven clinical trials (CTs) and seven case reports (CRs)] were included in the review. In infants with confirmed or suspected CMA, the use of an AAF was shown to be safe and efficacious. Findings from RCT comparisons of AAF with eHF showed that both formulas are equally efficacious at relieving the symptoms of CMA in confirmed or suspected cases. However, infants in specific subgroups (e.g. non-IgE mediated food-induced gastro-enterocolitis-proctitis syndromes with failure to thrive, severe atopic eczema, or with symptoms during exclusive breastfeeding) were more likely overall to benefit from AAF, as intolerance to eHF may occur. In such cases, symptoms persisting despite eHF feeding usually remit on AAF, and catch-up growth may be seen. Meta-analysis of the findings was not possible due to lack of homogenous reporting of outcomes in the original trials. This systematic review shows clinical benefit from use of AAF in both symptoms and growth in infants and children with CMA who fail to tolerate eHF. Further studies are required to determine the relative medical or economic value of initial treatment with AAF in infants at high risk of eHF intolerance.

Serum activity of dipeptidyl peptidase IV (DPPIV; EC 3.4.14.5) in breast-fed infants with symptoms of allergy

Beta-casomorphins, opioid peptides present in mother's milk, are a good substrate for DPPIV (EC 3.4.14.5) which is a major factor limiting the half-life of biologically active peptides. Serum DPPIV activity of two groups of infants (healthy and atopic dermatitis) and contents of beta-casomorphin-5 and -7 in their mothers' milk were determined in the study. We have found correlation between those two parameters in the group of children with atopic dermatitis syndromes, while no such a correlation was found in the control group.

Rectal bleeding in infancy: clinical, allergological, and microbiological examination

OBJECTIVE

Rectal bleeding is an alarming symptom and requires additional investigation. In infants it has been explained mainly by hypersensitivity. In addition to dietary antigens, intraluminal microbial agents challenge the immature gut mucosa. Although controlled in the mature gut, these antigens may induce inflammation in the developing gastrointestinal tract. The objectives of this study were to evaluate prospectively the clinical course of rectal bleeding and evaluate the impact of cow's milk allergy and aberrant gut microbiota on the condition. Because withdrawal of cow's milk antigens from the infants' diet is used as a first treatment without evidence of its efficacy, we also aimed to asses the effect of a cow's milk-elimination diet on the duration of rectal bleeding.

METHODS

The study involved 40 consecutive infants (mean age: 2.7 months) with visible rectal bleeding during a 2-year period at the Tampere University Hospital Department of Pediatrics. Most of the infants (68%) were fully breastfed. At enrollment the infants were randomly allocated to receive a cow's milk-elimination diet (n = 19) or continue their previous diet (n = 21) for 1 month. Findings of colonoscopy, fecal bacterial culture, fluorescence in situ hybridization of selected gut genera, specific detection of fecal enteroviruses, rotaviruses, and adenoviruses, fecal electron microscopy for viruses, and mucosal electron microscopy for viruses were assessed. During each visit the severity of atopic eczema, if any, was assessed according to the SCORAD method. In evaluating the extent of sensitization, serum total immunoglobulin E (IgE) and specific IgE and skin-prick tests for cow's milk, egg, and wheat were studied. Cow's milk allergy was diagnosed by elimination and provocation testing. Five patients were hospitalized; all others were treated on an outpatient basis. The follow-up visits were scheduled 1 month later and at the age of 1 year. Sixty-four healthy reference infants were selected as controls according to the following criteria: age and timing of fecal sampling being identical to within 1 month.

RESULTS

Altogether, 32 (80%) infants manifested bloody stools during follow-up (mean [range]: 2.1 [1-15] per day). The mean number of days with rectal bleeding on follow-up was 6. Typically, bloody stools occurred irregularly, for which reason the mean time to the last occurrence of rectal bleeding was 24 (range: 1-85) days from admission. Atopic eczema at presentation or during follow-up was diagnosed in 38% of the infants. Increased specific IgE concentrations or a positive skin-prick test were uncommon. The growth of the infants was normal on admission and during follow-up. Colonoscopy revealed typically focal mucosal erythema and aphthous ulcerations. The mucosa appeared normal in less than half of the patients. No anorectal fissures or colonic polyps were found. Light microscopy revealed that the overall architecture of the mucosa was well maintained. Acute inflammation or postinflammatory state and focal infiltration of eosinophils in the lamina propria were the most common abnormalities. A cow's milk-elimination diet did not affect the duration of rectal bleeding. Cow's milk allergy was diagnosed in 7 (18%) patients. Virus-particle aggregates were found in the microvillus layer of the colon epithelium in 8 cases. The surface epithelium of the virus-positive colon biopsy specimens regularly showed degenerative changes in the microvillus layer and epithelial cells. Electron microscopy study of the colon biopsies disclosed virus particles (30 nm in diameter) on the surface of epithelial cells. Virus particles or RNA were present in feces in only a minority of the patients. All fecal cultures were negative for Salmonella, Shigella, and Yersinia. Campylobacter jejuni was found in the feces of 1 patient, and fecal cultures were positive for Clostridium difficile in 4 patients, Staphylococcus aureus in 8 patients, and yeast in 2 patients. Fluorescence in situ hybridization revealed that at the time of admission the total numbers of bacteria and the numbers of bifidobacteria and lactobacilli in feces were lower in the patients compared with controls. The fecal concentrations of microbes characterized in this study (Bacteroides, bifidobacteria, Clostridium, lactobacilli, and enterococci) did not differ significantly between the time of admission and the second visit in the patients or controls. At the age of 1 year, 7 patients still suffered from cow's milk allergy, 5 of whom also suffered from multiple food allergies. Atopic eczema and histopathologically confirmed inflammation of the colonic mucosa at presentation were associated with persistence of cow's milk allergy at the age of 1 year. No patients exhibited gastrointestinal complaints or visible blood in stools.

CONCLUSIONS

Rectal bleeding in infants is generally a benign and self-limiting disorder. Bloody stools occurred irregularly for only a few days during the following months. As in a previous report, most infants were exclusively breastfed. In the majority of the patients the cause of the condition remains unknown. An association with viruses can be seen in some patients. The microbes that commonly lead to bloody diarrhea in older children and adults, Salmonella, Shigella, and Yersinia, were absent in the present material. The low bifidobacterial numbers in fecal samples may indicate a significant aberrance that may provide a target for probiotic intervention to normalize gut microbiota. The gut microbiota overall seemed stable, because the numbers of major groups of microbiota tested did not change significantly between the time of admission and after 1 month. Cow's milk allergy among these patients is more uncommon than previously believed. Cow's milk challenge is thus essential in infants who become symptom-free during a cow's milk-free diet to reduce the number of false-positive cow's milk-allergy diagnoses.

Probiotics: a complementary approach in the treatment and prevention of pediatric atopic disease

PURPOSE OF REVIEW

The goal of this article is to review recent primary research and developments in the area of probiotics and pediatric atopic disease.

RECENT FINDINGS

Research developments in probiotics summarized in this article include the following: (1) the role of probiotics in primary prevention of atopic disease, (2) the effect of probiotics on cytokines involved in the allergic immune response, (3) the long-term effects of peri-natal probiotic use and (4) the relationship between the gut microflora and atopic dermatitis.

SUMMARY

Probiotics continue to be an area of active investigation as our understanding evolves of the gut microbiota's role in the altered immune response of atopic patients. Physicians should be aware of these developments as probiotics may be an important complementary approach in the treatment and the natural and long-term course of various pediatric diseases. This article summarizes the research conducted over the past 10 years with a primary focus on the literature published since January 2003.

Spray-dried porcine plasma reduces the effects of staphylococcal enterotoxin B on glucose transport in rat intestine

We investigated the intestinal transport of D-glucose (D-Glc) and 3 essential amino acids in a model of intestinal inflammation, and the effects of dietary supplementation with animal plasma proteins on this function. Wistar Lewis rats were fed a diet containing an isonitrogenous amount of milk protein (control group) or a diet supplemented with either spray-dried animal plasma (SDAP) or immunoglobulin concentrate (IC) from porcine plasma, from d 21 of life (weaning) until d 35. On d 30 and 33, rats were challenged intraperitoneally with Staphylococcus aureus enterotoxin B (SEB; groups SEB, SEB-SDAP, and SEB-IC) and on d 35, brush border membrane vesicles (BBMVs) were prepared and used for transport and binding studies. Administration of SEB reduced D-Glc transport across sodium glucose transporter 1 [SGLT1; 20% reduction in maximal transport rate (Vmax); P < 0.05], without affecting the Michaelis constant (Km). The results from specific phlorizin binding, Western blot, and immunohistochemistry supported the view that the effects of SEB are due to reduced expression of D-Glc transporters in the apical membrane. SEB increased the passive diffusion constant (Kd) for D-Glc 3-fold (P < 0.05). SEB did not affect mediated or passive amino acid fluxes of L-leucine, L-methionine, or L-lysine. Dietary SDAP increased the D-Glc Vmax in the SEB group without affecting the passive component. Changes in d-Glc Vmax due to SEB and to the dietary treatments were correlated with changes in the number of SGLT1 transporters present in the BBMVs (r = 0.9468; P < 0.05). Dietary IC had no observed effect. We estimate that, in rats challenged with SEB, SDAP supplementation can increase glucose absorption by 8-9% during the interdigestive periods.