Cashew Allergy Prevalence and Sensitization in 1-Year-Old Infants

The study aimed to report the prevalence of cashew allergy and sensitization in infants at 12 months of age. They also looked at the association with concomitant eczema and sensitization to milk, egg, and/or peanut. Questionnaires also assessed demographic data, food allergy risk factors, details of the cashew reactions, and timing of cashew introduction into the infant’s diet.Families with 1-year-old infants were recruited from immunization centers in Melbourne between 2016 and 2019.The study was a cross-sectional study that evaluated the prevalence of food allergies, particularly cashew allergy, in 1-year-old infants in Melbourne between 2016 and 2019. Infants underwent skin prick tests for cow’s milk, egg, peanut, and cashew. Infants with a skin prick test 1 mm or greater were invited to undergo an oral food challenge to that food. Data on risk factors for cashew allergy, including other food allergies, eczema, timing of cashew introduction, and family history of allergies, were collected through questionnaires and clinical assessments. These variables were analyzed using multivariable logistic regression models.The prevalence of cashew allergy at 12 months was 1.49%, and cashew sensitization (+ skin test regardless of clinical history or outcome of oral food challenge) was 1.96% using a 3 mm skin prick test cutoff. The study found that only 25% of participants were introduced to cashews before 12 months of age. However, early introduction of cashew (before 12 months) did not differ significantly between infants who developed a cashew allergy and those who did not. Cashew allergy and sensitization were more common in infants with eczema or peanut allergy.Cashew allergy has been described in older children, but this study is the first to explore the prevalence and risk factors for cashew sensitization and allergy in infants. Although early cashew introduction increased from 5% to 25% over a decade, most infants were still not introduced to cashew before 12 months, and no link was found between the timing of introduction and cashew allergy. These findings highlight the need for more research on early prevention strategies.As the paradigm shift in food allergy management has shifted to early introduction to prevent food allergies, more data are needed on these individual foods. Can the data we have for peanut, milk and egg be extrapolated to other major food allergens? In this study, early introduction of cashew did not show a significant difference in development of cashew allergy and sensitization. This highlights the need for further research on the timing of cashew introduction to better understand its potential role in allergy prevention. Future studies designed to proactively answer this question will be able to better define whether there is an association with early introduction of cashew and lower risk of cashew allergy.