Food Allergy Prevention: More Than Peanut

Management of evidence and conflict of interest in guidelines on early childhood allergy prevention and child nutrition: study protocol of a systematic synthesis of guidelines and explorative network analysis

Background

With the rising prevalence of allergic diseases in children, prevention of childhood allergies becomes an important public health issue. Recently, a paradigm shift is taking place in the approach to preventing allergies, and clinical practice guidelines (CPG) and food-based dietary guidelines (FBDG) play an important role in providing practitioners with the latest evidence and reliable guidance. However, concern about the methodological quality of the development of FBDGs and CPGs, including limitations in the systematic reviews, lack of transparency and unmanaged conflicts of interest (COI), reduce the trust in these guidelines.

Methods

We aim to synthesize the available guidance on early childhood allergy prevention (ECAP) through a systematic search for national and international CPGs and FBDGs concerning ECAP and child nutrition (CN) and to assess the quality of the guidelines and management of COI. Additionally, we will analyse the content and the evidence base of the recommendation statements. We aim to quantify the COI in guideline panellists and explore possible associations between COI and recommendations. Through a social network analysis, we expect to elucidate ties between panellists, researchers, institutions, industry and other sponsors. Guidelines are an important tool to inform healthcare practitioners with the newest evidence, but quality and reliability have to be high. This study will help identify potential for further improvement in the development of guidelines and the management of COI. If the social network analysis proves feasible and reveals more information on COI in comparison to disclosed COI from the previous analyses, the methodology can be developed further to identify undisclosed COIs in panelists.

Ethics and dissemination

This research does not require ethical approval because no human subjects are involved. Results will be published in international peer-reviewed open access journals and via presentations at scientific conferences.

Timing of Cow's Milk Protein Introduction and Childhood Adverse Reactions to Cow's Milk

BACKGROUND

Current guidelines emphasize early introduction to potentially allergenic foods, but the optimal timing, amount, and exposure routes for foods other than peanut are not well-established. Cow's milk is often the first allergenic food introduced through infant formulas.

OBJECTIVE

To examine timing of cow's milk protein introduction (CMPI), including interaction with formula supplementation after delivery, in relation to reported cow's milk adverse reactions throughout childhood.

METHODS

Among children in the Boston, Mass-area Project Viva cohort, we assessed timing of CMPI (<2 weeks, 2 weeks-<6 months, ≥6 months) with questionnaires administered in infancy. Outcomes were (1) parent-reported cow's milk adverse reactions via annual questionnaires from age 2 to 13 years (n = 1298) and (2) milk sensitization (n = 505) and IgE-mediated milk allergy (n = 491) at age approximately 8 years. We used multivariable logistic regression models adjusted for parental atopy history, delivery mode, gestational age at delivery, child race, and census tract median household income, and investigated effect modification by ever/never breast-fed status and formula supplementation in the delivery hospital.

RESULTS

A total of 32% were introduced to cow's milk protein at age less than 2 weeks, 38% at age 2 weeks to less than 6 months, and 30% at age 6 months or more. Compared with children with CMPI at age less than 2 weeks, children with CMPI at age 6 months or more had a higher risk of cow's milk adverse reaction at age 2 to 5 years (odds ratio, 2.4 [1.2-4.7]). Children given formula after delivery + CMPI at age less than 2 weeks had the lowest risk overall. Among children not given formula after delivery, CMPI at age 2 weeks to 6 months appeared most protective. Results were similar among ever-breast-fed children. Timing of CMPI was not associated with milk sensitization or IgE-mediated milk allergy in mid-childhood.

CONCLUSIONS

Early, consistent cow's milk exposure appears protective against adverse reactions to cow's milk.

How primary care providers can help prevent food allergies

PURPOSE OF REVIEW

IgE-mediated food allergy rates have increased in recent decades, yet treatment options remain limited. Prevention strategies are thus essential. We will review recent research and consensus guidelines for food allergy prevention.

RECENT FINDINGS

Research has continued to support that early introduction of allergens via the gastrointestinal tract induces tolerance and prevents development of food allergy. In contrast, allergen sensitization may occur via transcutaneous allergen exposure. This is supported by research that shows a decreased risk of food allergy with aggressive treatment of atopic dermatitis. More recent research suggests that transcutaneous sensitization could also be facilitated by frequent emollient use in the absence of atopic dermatitis but definitive research is lacking. Murine models have shown a likely role of dysbiosis, or disruption of the body's normal healthy microbiome, in development of food allergy, yet human studies have yet to show a conclusive benefit of probiotics in the prevention of food allergy.

SUMMARY

Important approaches for food allergy prevention are: introduction of peanut and cooked egg at 4-6 months, early introduction of other allergenic foods, and early diagnosis and treatment of atopic dermatitis (because of a predisposition to food sensitization through the damaged skin barrier). More research is needed to clarify the role, if any, of emollient use and probiotics.

Labeling food allergens in the packaged food pyramid groups in Brazil: analysis of descriptions, ambiguities, and risks

OBJECTIVE

The aim of this study was to evaluate allergenic labeling components of packaged foods for "What is the quality of food labels?" and "What is the group of Brazilian Food Pyramid that 'May contain' is predominant?."

METHODS

The photographs of 916 products were obtained, of which 518 were analyzed. Data from each label were evaluated according to Brazilian Food Pyramid Groups (i.e., Cereals, Fruits, & Vegetables; Soybean & products; Milk & dairy products; Meat & eggs; Fats & oils; and Sugars & sweets). Ten items were analyzed in each label, namely, the presence of a list of ingredients, alert phrase for allergy sufferers, grouping of the alert phrase, phrase location, uppercase phrase, the phrase in bold, the color of alert phrase contrasting to the background, adequate font size, do not claim the absence for any allergen with the ingredients, and others factors that make it difficult to read. For the second question, a structured questionnaire was completed, and products were classified into two categories, namely, "Contain" and "May contain."

RESULTS

The quality of the label was appropriate, and 69% of packaged foods had at least one allergen. The information "May contain" were higher in cow's milk (Cereals and Meat & eggs), soy (Soybean & products), and egg protein (Cereals). Soybean & products were the highest insecurity group.

CONCLUSIONS

Brazilian health professionals can count on good-quality labeling of packaged products. Consequently, they could promote patients' and parents/caregivers' education to consult the labels and manage the risks in processed foods about precautionary allergen labeling. Soybean & products were the most significant insecurity for food choices between Brazilian Pyramid Groups.

Food Protein-Induced Allergic Proctocolitis: The Effect of Maternal Diet During Pregnancy and Breastfeeding in a Mediterranean Population

Background

The aim of the current investigation was to explore the association of food protein-induced allergic proctocolitis (FPIAP) with the maternal diet during pregnancy and breastfeeding in Greek infants.

Methods

A multicenter retrospective case-control study was conducted in 6 regions in Greece, with 96 mothers of infants with and 141 mothers of infants without a history of FPIAP. Maternal dietary habits during pregnancy and breastfeeding were evaluated with the following validated questionnaires: (a) The Mediterranean Diet Score and (b) The Mediterranean Oriented Culture-Specific Semi-Quantitative Food Frequency Questionnaire.

Results

FPIAP was associated with cow's milk (83.6%), egg (7.3%), wheat (6.4%), and beef (6.4%) in the maternal diet. Adherence to Mediterranean Diet was similar among the mothers. Mothers of FPIAP infants consumed more vegetables. Elastic net prediction models showed that, in this Mediterranean population, increased consumption during pregnancy and lactation of common allergens, whole grain products, homemade food, fish and shellfish, and fruits was associated with a decreased risk of FPIAP. Conversely, a high intake of vegetables, sugar and total fat, and non-stick/grilled cooking, were associated with increased risk of FPIAP, as was a high intake of salt and white flour during lactation only.

Conclusions

Components of a maternal Mediterranean Diet may protect against FPIAP when traditional cooking methods are adopted and fish, fruit, and whole wheat products are consumed frequently during pregnancy and breastfeeding.

Rotulagem de alérgenos alimentares em alimentos embalados segundo grupos alimentares da pirâmide brasileira: análise da descrição, riscos e ambiguidades

RESUMO Objetivo: Avaliar os componentes alergênicos da rotulagem de alimentos embalados e responder “Qual é a qualidade da rotulagem?” e “Qual é o grupo de alimentos em que a expressão ‘Pode conter’ é predominante?”. Métodos: Foram obtidas fotografias de 916 produtos, dos quais 518 foram analisados. Os dados dos rótulos foram avaliados de acordo com os grupos da pirâmide alimentar brasileira (Cereais, Frutas & Vegetais; Soja & Derivados; Leite & Laticínios; Carne & Ovos; Gorduras & Óleos; Açúcares & Doces). Dez itens foram analisados nos rótulos: presença de lista de ingredientes; frase de alerta para alérgicos; frase de alerta; local da frase; frase em letras maiúsculas; frase em negrito; a cor da frase de alerta contrastando com o fundo; tamanho de fonte adequado; não alegar ausência de qualquer alérgeno; outros fatores de difícil leitura. Para a segunda questão, foi respondido questionário estruturado, e os produtos classificados em categorias: “Contém” e “Pode conter”. Resultados: A qualidade do rótulo foi adequada e 69% dos alimentos embalados continham pelo menos um alérgeno. A informação “Pode conter” foi mais identificada em: proteína do leite (Cereais e Carnes e ovos), soja (Soja & derivados) e proteína do ovo (Cereais). Soja e derivados foi o grupo alimentar de maior insegurança. Conclusões: Profissionais de saúde podem contar com rotulagem de boa qualidade dos produtos embalados e, consequentemente, promover a educação de pais/cuidadores para consultar os rótulos e gerenciar os riscos em alimentos processados. Soja e produtos são os alimentos com maior insegurança entre os Grupos da Pirâmide Brasileira.

Managing Food Allergy When the Patient Is Not Highly Allergic

Few patients with food allergy are "highly allergic," meaning they always have severe reactions and always react to very small amounts of allergen. Standard medical approaches for allergy management have focused on the safety and lifestyle modifications this group truly needs, but consequently families with food allergy are typically advised to strictly avoid any exposure to their implicated allergens. Most food-allergic subjects are actually not reactive to very low doses, and many never experience severe reactions. There are also notable conditions where a different care plan is already commonly offered: patients with pollen-related food allergy syndrome, with food-associated exercise-induced anaphylaxis, and with resolving or mild milk or egg allergy might be advised to ingest the allergens in specific circumstances with detailed instructions. Because oral immunotherapy and allergy prevention by early exposure have emphasized alternatives to strict avoidance, there is increasing interest in prospects to forego strict avoidance in those with food allergy. For patients with a high threshold of reactivity (low-dose tolerant, high-dose mildly reactive), there may be options such as allowing the ingestion of products with precautionary allergen labels, allowing dietary indiscretions with small amounts of the allergen, or even encouraging ingestion of subthreshold amounts with therapeutic intent. These practices have not been extensively studied and could be considered controversial. If these approaches are considered, shared decision making is needed in discussing them with patients and families. This review considers the potential approaches to those who are "not highly allergic": the risks, benefits, shared decision making, and research needs.

Sensitization with Eustrongylides sp. (Nematoda: Dioctophymatidae) antigens induce production of specific IgG and IgE in murine model

Fish consumption plays an important role in human diet. Hoplias malabaricus, commonly known as traíra, is a freshwater fish widely appreciated in several Brazilian states and frequently infected by Eustrongylides sp. fourth-instar larvae (L4). The aim of the present study was to evaluate allergenic potential of Eustrongylides sp. L4 crude extract (CEE). BALB/c mice were immunized intraperitoneally (IP) by 10 μg CEE with 2 mg of aluminum hydroxide on days 0 and 35. Specific IgG and IgE antibody levels were determined after immunization and cellular immunity was evaluated by assessing intradermal reaction in ear pavilion. Epicutaneous sensitization was performed in dorsal region by antigen exposure using a Finn-type chamber containing 50 μg of CEE or saline solution, followed by evaluation of specific antibody levels. IP immunization resulted in a gradual increase in IgG antibody levels and transitory IgE production. Significant increase in ear thickness was observed in cellular hypersensitivity reaction. In case of antigen exposure by epicutaneous route, CEE was able to induce meaningfully increased levels of specific IgG and IgE antibodies as well as heightened cellular immunity. Both intraperitoneal immunization and epicutaneous contact with Eustrongylides sp. larval antigens were observed for first time to be capable of inducing immunological sensitization in mice.