Pistachio and cashew nut allergy in childhood: Predictive factors towards development of a decision tree.

BACKGROUND: Pistachio and cashew nut, which belong to the same botanical family, are tree nuts that induce serious allergic reactions. OBJECTIVE: We aimed to determine the predictive factors for pistachio and cashew nut reactivity during oral food challenge (OFC). METHODS: A total of 112 pistachio and/or cashew nut sensitized children, aged 58.45 (IQR:40.38-88.32) months, were included. Cutoff values and probability curves for skin prick test (SPT), sIgE, sIgE/Total IgE that predict reactivity were determined for pistachio and cashew nut. Additionally, a diagram was created that can be useful while making a decision for OFC based on SPT and sIgE values. RESULTS: A total of 73 patients underwent OFC with pistachio and/or cashew nut. Twelve children with current anaphylaxis history were not challenged and accepted as allergic. SPT was the only predictive factor for positive pistachio/ cashew nut OFC. According to area under curve (AUC) analysis, SPT was more predictive than sIgE and sIgE/Total IgE both for pistachio and cashew nut. Optimal cutoff values according to "Youden index" for pistachio SPT, sIgE, and sIgE/ Total IgE were 7.25 mm, 4.14 kUA/L, and 1.32%, respectively. And those values for cashew nut SPT, sIgE, and sIgE/Total IgE were 6.25 mm, 1.125 kUA/L, and 3.30%, respectively. The diagram showed that SPT predicted the reactivity together with sIgE better than only the SPT values. CONCLUSION: SPT was the best predictor for reactivity both for pistachio and cashew nut. Combined use of SPT and sIgE may improve the prediction of reactivity at pistachio and cashew nut OFCs in children.

Updated population minimal eliciting dose distributions for use in risk assessment of 14 priority food allergens.

Food allergy and allergen management are important global public health issues. In 2011, the first iteration of our allergen threshold database (ATDB) was established based on individual NOAELs and LOAELs from oral food challenge in roughly 1750 allergic individuals. Population minimal eliciting dose (EDp) distributions based on this dataset were published for 11 allergenic foods in 2014. Systematic data collection has continued (2011-2018) and the dataset now contains over 3400 data points. The current study provides new and updated EDp values for 14 allergenic foods and incorporates a newly developed Stacked Model Averaging statistical method for interval-censored data. ED01 and ED05 values, the doses at which 1%, and respectively 5%, of the respective allergic population would be predicted to experience any objective allergic reaction were determined. The 14 allergenic foods were cashew, celery, egg, fish, hazelnut, lupine, milk, mustard, peanut, sesame, shrimp (for crustacean shellfish), soy, walnut, and wheat. Updated ED01 estimates ranged between 0.03 mg for walnut protein and 26.2 mg for shrimp protein. ED05 estimates ranged between 0.4 mg for mustard protein and 280 mg for shrimp protein. The ED01 and ED05 values presented here are valuable in the risk assessment and subsequent risk management of allergenic foods.

Allergenicity assessment of Buchanania lanzan protein extract in Balb/c mice.

Tree nuts are among "Big Eight" and have been reported globally for causing allergy. Buchanania lanzan (Bl) is one of the major tree nuts consumed by Indian population. However, very little is known about B. lanzan's induced allergic manifestation. Therefore, evaluation of it's allergenic potential was undertaken. Bl-crude protein extract sensitized BALB/c mice sera were used to identify the allergic proteins by it's IgE binding capability. The major IgE binding proteins found with molecular weight of 11, 20, 23, 25, 48, 54, and 65 kDa. Specific IgE, specific IgG1, MCPT-1, PGD2 and histamine were assessed in mice sera. Enormous amount of mast cell infiltration was noted in different organs. The levels of Th1/Th2 transcription factors GATA-3, SOCS3 and STAT-6 were found upregulated, whereas T-bet was downregulated. Furthermore, elevated Th1/Th2 cytokine responses were observed in mice sera. All together, these reactions developed systemic anaphylaxis upon Bl-CPE challenge in sensitized BALB/c mice. In order to confirm the evidences obtained from the studies carried out in BALB/c, the investigation was extended to human subjects as well. Control subjects and allergic patients were subjected to skin prick test (SPT). Later sera collected from those positive to SPT along with controls were used for IgE immunoblotting. The study evaluated the allergic manifestation associated with Bl, and identified it's proteins attributing Bl-mediated allergy. This work may help in managing tree nuts mediated allergies especially due to Buchanania lanzan sensitization.

Risk assessment and food allergy: the probabilistic model applied to allergens.

In order to assess the risk of unintended exposure to food allergens, traditional deterministic risk assessment is usually applied, leading to inconsequential conclusions as 'an allergic reaction cannot be excluded'. TNO therefore developed a quantitative risk assessment model for allergens based on probabilistic techniques resulting in a more exhaustive risk assessment and more detailed information. By now, this approach is recognized as the future approach in allergen risk assessment. A case study (hazelnut proteins in chocolate spread) is presented as a proof of concept.