Sensitivity of prick test with walnut commercial extracts and of prick by prick with raw walnut compared with open food challenge in walnut allergy Low SPT sensitivity in walnut allergy

Main Article Content

Maria Letizia Patti
Cristina De Rose
Federica Brancato
Alessandro Gambacorta
Stefano Miceli Sopo

Keywords

Diagnosis, prick by prick, sensitivity, skin prick test, walnut allergy

Abstract

Background and aim


Diagnosis of walnut allergy includes the evaluation of IgE sensitization by skin prick tests (SPT) with standardized commercial extracts. When assuming the loss of relevant allergens due to extract preparation and storage, it is possible to perform SPT with fresh foods, i.e. prick by prick (PbP). To our knowledge, there is no published comparison between SPT with commercial extracts and PbP with fresh food about their sensitivity to the diagnosis of walnut allergy. Therefore, we describe our experience.


Methods


We observed seven children (mean age + SD  6.8 years + 5.2, range  2 - 15 years; male 85%) with an history of immediate adverse reaction following walnut ingestion. All but one the patients underwent SPT with at least two out of three walnut commercial extracts (Lofarma, Milan, Italy; ALK-Abellò, Milan, Italy; Allergopharma, Rome, Italy). It has also been performed PbP with raw walnut. IgE-mediated walnut allergy was diagnosed based on suggestive history,  positivity of PbP and failed open food challenge with walnut.


Results


The SPT with Lofarma extract was never positive (sensitivity = 0%), that performed with  ALK extract was positive in 2/5 cases (sensitivity 40%) and that of Allergopharma extract was positive in 1/5 cases (sensitivity  20%). PbP was positive in 7/7 cases (sensitivity  100%).


Conclusions


In the specific case of walnut allergy in pediatric age, the execution of SPT alone with commercial extract may not be sufficient and clarifying in the diagnostic iter. We suggest to always associate the execution of PbP test.

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References

1. Stiefel G, Anagnostou K, Boyle RJ, Brathwaite N, Ewan P, Fox AT, et al. BSACI guideline for the diagnosis and management of peanut and tree nut allergy. Clin Exp Allergy 2017; 47: 719-739.
2. Sampson HA, Muñoz-Furlong A, Campbell RL, Adkinson NF Jr, Bock SA, Branum A, et al. Second symposium on the definition and management of anaphylaxis: summary report--second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network symposium. Ann Emerg Med 2006;47:373-80.
3. Heinzerling L, Mari A, Bergmann KC, Bresciani M, Burbach G, Darsow U, et al. The skin prick test - European standards. Clin Transl Allergy 2013; 3: 3.
4. Sampson HA, Gerth van Wijk R, Bindslev-Jensen C, Sicherer S, Teuber SS, Burks AW, et al. Standardizing double-blind, placebo-controlled oral food challenges: American Academy of Allergy, Asthma & Immunology-European Academy of Allergy and Clinical Immunology PRACTALL consensus report. J Allergy Clin Immunol 2012;130:1260-74.
5. Nowak-Wegrzyn A, Assa'ad AH, Bahna SL, Bock SA, Sicherer SH, Teuber SS; Adverse Reactions to Food Committee of American Academy of Allergy, Asthma & Immunology. Work Group report: oral food challenge testing. J Allergy Clin Immunol 2009;123(6 Suppl):S365-83.
6. Asaumi T, Ebisawa M. How to manage food dependent exercise induced anaphylaxis (FDEIA). Curr Opin Allergy Clin Immunol 2018;18:243-247.
7. Costa J, Carrapatoso I, Oliveira MBPP, Mafra I. Walnut allergens: molecular characterization detection and clinical relevance. Clin Exp Allergy 2014; 44:319 341.
8. http://www.allergen.org/viewallergen.php?aid=876.
9. Teuber SS, Dandekar AM, Peterson WR, Sellers CL. Cloning and sequencing of a gene encoding a 2S albumin seed storage protein precursor from English walnut (Juglans regia), a major food allergen. J Allergy Clin Immunol 1998; 101:807-14.
10. Pastorello EA, Farioli L, Pravettoni V, Obino AM, Scibilia J, Fortunato D, et al. Lipid transfer protein and vicilin are important walnut allergens in patients not allergic to pollen. J Allergy Clin Immunol. 2004;114:908-14.
11. Hauser M, Roulias A, Ferreira F, Egger M. Panallergens and their impact on the allergic patient. Allergy Asthma Clin Immunol 2010; 6:1-14.