Increased Rates of Peanut and Tree Nut Aspiration as a Possible Consequence of Allergy Prevention by Early Introduction

Timing of Food Introduction and Allergy Prevention: An Update

Recommendations about allergy prevention through diet are rapidly changing. In just the past several years, multiple organizations have provided updated guidance and recommendations about infant feeding based on recent studies and meta-analyses. In addition to the increased number of studies supporting the benefit of early introduction of allergenic foods, in particular peanut and egg, recent studies demonstrate that infant and maternal diet diversity may also reduce risk of food allergy and atopy. Skin emollients have not been found to be helpful in prevention of food allergy, and more evidence is needed to determine if emollients play a role in prevention of atopic dermatitis.

Assessing the Effect of Infant Peanut Exposure Guidelines on Peanut Aspiration Using Google Trends Search Analysis

Background The American Academy of Pediatrics (AAP) changed guidelines in 2017 to recommend introducing infants to peanuts as early as four months. Peanuts are also one of the most commonly aspirated food-related foreign bodies. Google Trends search pattern analysis has been validated in epidemiologic research as being reflective of healthcare events. Methodology Google Trends measures the popularity of a search term in a given week compared to the popularity of all search terms in that week, calculated as relative search volume (RSV), yielding a value between 0 and 100. We compiled peanut aspiration-related search data from January 2012 to January 2022 and compared the relative popularity of these searches before the change in guidelines to after. Results All queried search terms significantly increased in RSV when comparing the five years before and following January 2017. When pooling all terms, the median RSV increase was 13.8% (p < 0.001). "Choke on peanut" and the combination of peanut and cough had the highest median RSV increases from 9.6 to 17 and 50.8 to 63.1, respectively. Conclusions The change in 2017 of the AAP guidelines on early childhood peanut exposure was associated with an increase in online searches for peanut aspiration. This may be reflective of increased aspiration events, or possibly increased concern for aspiration. Current results support the need to closely counsel families on infant-safe peanut products to prevent dangerous aspiration events.

Infantile Peanut Introduction and Peanut Allergy in Regions With a Low Prevalence of Peanut Allergy: The Japan Environment and Children's Study (JECS)

BACKGROUND

In regions with a high prevalence of peanut allergy (PA), there is a consensus that the introduction of peanuts in early infancy is preventive against the development of PA. However, few studies have investigated whether the introduction of peanuts to infants is associated with PA in regions with a low prevalence of PA, including Japan.

METHODS

We used data from 74,240 mother-child pairs who participated in the Japan Environment and Children's Study, a prospective birth cohort recruited between January 2011 and March 2014. A logistic regression model was used to analyze the association between infantile peanut introduction and PA at the age of 4 years with non-infantile peanut introduction as the reference group, adjusted for potential confounders.

RESULTS

The percentage of infantile peanut introduction was 4.9% (n = 3,294), and 286 (0.4%) participants had allergic symptoms to peanuts at 4 years of age. Of all participants, 129 (0.2%) had PA at 4 years of age, which was defined as allergic symptoms and sensitization to peanuts. Those with infantile peanut introduction had a lower prevalence of PA than those without infantile peanut introduction, although this did not reach statistical significance (adjusted odds ratio 0.53; 95% confidence interval, 0.17-1.68). Sensitivity analysis using IgE-mediated symptoms caused by peanuts as the outcome showed a similar result in relation to infantile peanut introduction.

CONCLUSION

In countries with a low prevalence of PA, the effect of infantile peanut introduction on PA prevention was unclear.

Health Promotion of Early and Sustained Allergenic Food Introduction for the Prevention of Food Allergy

Observational studies and landmark randomized control trials support early and sustained allergenic food introduction in infancy as an effective preventive strategy against food allergy development. Despite a consensus regarding the intended goals of early and sustained allergenic food introduction, there have been myriad policy recommendations among health authorities in how to achieve both individual and population-level health outcomes for food allergy prevention. This clinical management review provides an overview on the data that informs early and sustained allergenic food introduction strategies, suggestions on how to advise allergenic food introduction, principles of prevention programs as they relate to food allergy prevention, and health promotion and systems-level challenges that impede achievement of food allergy prevention goals.

Principal diagnostic features of paediatric foreign body aspiration

OBJECTIVES

The aim of this study is to identify the most common and important features within the presenting history, clinical examination and chest radiograph that are associated with foreign body (FB) aspiration in the paediatric population, to support rationalised decision making in regards to proceeding with diagnostic bronchoscopy.

METHODS

A retrospective notes review was conducted of 70 patients over a 12-year period at our tertiary referral centre. Their presenting history, clinical and radiographic signs were documented and univariate logistic regression model used to calculate odds ratios.

RESULTS

The main features identified within our cohort with a positive FB finding at bronchoscopy were history of a cough (OR 5.1, p = 0.008) and radiographic evidence of hyperinflation or air trapping (OR 7.1, p = 0.016). Zero patients with a FB presented with only a positive history in the absence of other clinical or radiological signs. History of a witnessed choking episode neither increased or decreased the likelihood of as aspirated FB (OR 1, p = 0.967).

CONCLUSIONS

We have identified two principal features, as described above, which are associated with paediatric FB aspiration. Reliance on a positive clinical history alone, but specifically the history of a witnessed choking episode, did not support the presence of a FB and other associated signs need to be considered in deciding to proceed to bronchoscopy.

Early peanut introduction: To test or not to test?

OBJECTIVE

To review recent evidence and international guidelines on early peanut introduction for preventing peanut allergy and provide an update on the status of the debate around testing before early peanut introduction.

DATA SOURCES

Review of published literature documenting: infant feeding guidelines; impact of early peanut introduction on peanut allergy; risk factors for peanut allergy; and impact of early peanut introduction guidelines on infant feeding practices and allergy.

STUDY SELECTION

We used a narrative approach and present both pro and con arguments for testing before peanut introduction. Data from randomized controlled trials and post-hoc analyses of these trials and observational studies were included.

RESULTS

Allergy prevention guidelines around the world now consistently recommend introducing peanut into an infant's diet before 12 months of age for countries with high peanut allergy prevalence. In the US, guidelines recently shifted away from recommending allergy testing before introduction for those at risk of peanut allergy. There is evidence primarily from Australia that recommending early introduction without prior testing is safe and effective in increasing early peanut introduction for both high and low-risk infants, although the subsequent reduction in peanut allergy prevalence at the population level was less than expected.

CONCLUSION

Current evidence supports recommending early peanut introduction without routinely testing for peanut allergy. If testing is offered, this should be based on shared decision making between families and practitioners and only be undertaken where there is provision for rapid access to definitive diagnosis including oral food challenges.

Effect of Processing on the Structure and Allergenicity of Peanut Allergen Ara h 2 Roasted in a Matrix

Peanut allergy is the leading pediatric food allergy. Many attempts have been made to reduce its allergenicity by processing. After roasting, Ara h 2 and its derivatives in the matrix were isolated by immunoaffinity chromatography (IAC). The structure and allergenicity of Ara h 2 were analyzed by circular dichroism, mass spectrometry (MS), western blotting, the enzyme-linked immunoassay, and cell modeling. Our results showed that a large portion of Ara h 2 was fragmented and cross-linked. Ara h 2 monomers accounted for only 13% of the total proteins after IAC purification. In addition, the structure of Ara h 2 changed after roasting. In addition to methylation and oxidation modification, the disulfide bonds of Ara h 2 were found to be rearranged after roasting. In the conformational structure of Ara h 2, the content of the α-helix decreased from 27.1 to 21.6% after roasting, while the content of the random coil increased from 29.1 to 34.3%. Six cleavage sites of trypsin were exposed, while three were covered. In terms of allergenicity, most of the cross-linking products were not recognized by patients' sera. Only one faint band around 40 kDa was observed in our blotting. For Ara h 2 monomers, roasting enhanced their IgE binding capacity and ability to stimulate the degranulation of basophils. The potential allergenicity increase of Ara h 2 monomers did not reflect the allergenicity change of Ara h 2 in the matrix due to the amount and property of its derivatives after roasting.

The year in food allergy

Research into food allergy continues to rapidly evolve, accompanying and driving real changes in the clinical approach to these diseases. The past year has seen the rollout of the first treatment approved for active management of food allergy, more data on alternative methods of treatment, the continued evolution of strategies for prevention of food allergy, a renewed interest in phenotyping food allergy subtypes, and, importantly, key new insights into the pathophysiology of food allergy. We expect that in the coming years, the therapies that are in preclinical or early clinical evaluation now will make their way to the clinic, finally allowing the possibility of safe and effective treatments for food allergy.

Real-World LEAP Implementation

PURPOSE OF REVIEW

In 2015, findings from the Learning Early About Peanut allergy (LEAP) trial provided the first convincing evidence that peanut allergy may be preventable through early peanut introduction into the infant diet. Here we discuss implementation of the LEAP study findings around the world and emerging evidence of the impacts on infant feeding and food allergy.

RECENT FINDINGS

The LEAP findings led to rapid changes in allergy prevention guidelines internationally to recommend early peanut introduction. There is now emerging evidence that this has been followed by a substantial increase in early peanut introduction to infants. Studies investigating the impact of these changes in infant feeding practices on the prevalence of peanut allergy are underway. The LEAP trial represented a significant step forwards in food allergy prevention and new research over the past 5 years has provided insights into how best to implement this intervention in the real world.