Trophallergen Prick Tests (PT) : Influence of Food Sample Shelf Life on the Reproducibility of PT Results

NCT06872996 | Recruiting

• 1 other identifier: CHUO-2024-19
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Prick tests (PT) are the standard skin tests used in the investigation of immediate IgE-mediated food allergies. Their use as a first-line tool in allergological investigations is strongly recommended by the European Academy of Allergy and Clinical Immunology (EAACI). These tests involve locally reproducing histamine release manifestations in the epidermis by superficially introducing an allergen to confirm or rule out its role in the onset of clinical symptoms compatible with an allergy. During the diagnostic management and follow-up of patients with food allergies, the technique used is the "prick to prick" method, due to the lack of reliable access to many standardized commercial food extracts. This method involves piercing the food with a sterile lancet (to deposit food content on its surface) and then making a superficial skin puncture with the same device on the anterior surface of the forearm to introduce a tiny fraction of the food and its proteins into the epidermis, where mast cells are present. Simultaneously, a positive control and a negative control are performed. The tests are read after 15 to 20 minutes by measuring the size in millimeters of the resulting papules and erythema. A PT for the tested allergen is considered positive if the average diameter of the resulting papule is 3 mm or more and/or at least half the size of the positive control papule. The procedure is well-tolerated, allowing it to be performed at any age, in both hospital and outpatient settings. The risk of a systemic reaction has been evaluated at 0.008%, with no severe reactions observed. This method, performed with native foods (unprocessed food, uncontaminated foods), either raw or cooked (depending on the nature of the allergen being tested), is preferred over the use of commercial extracts (standardized commercial allergen preparations) due to its better sensitivity and specificity, the high cost of commercial extracts, and the lack of commercial extracts for certain foods. For practical reasons, given the wide variety of possible allergens, and to most accurately reproduce the exposure that caused the reaction, the most common approach is to ask the patient to bring their own foods for testing. These foods should be brought in a fresh state. However, situations where the patient is offered a food PT but does not have fresh native foods are common. Indeed, many patients forget to bring them. Similarly, during a consultation to explore a respiratory or drug allergy, the interview may lead to the detection of a food allergy that needs to be tested at the same time. Given the delays in allergology consultations, the severity of food allergy symptoms, and the potential risk of delayed diagnosis, all allergists involved in managing food allergies are led to create a library of food samples stored either in a dry state (e.g., nuts, peanuts, cereal flours) or frozen for perishable foods (meats, shellfish, fruits, vegetables). To our knowledge, after reviewing the literature, no guidelines for best practices regarding the storage of these food samples for PT purposes have been established by scientific societies. Moreover, while the impact of freezing and thawing methods on the denaturation of food proteins is known, the effect of freezing and its duration on the sensitivity and specificity of PT is poorly understood. The objective of our study is to evaluate the reproducibility of PT results between those performed with fresh foods and those performed with preserved foods at different storage dates in participants who have experienced anaphylaxis of at least grade 2 according to the Ring and Messmer classification.

Conditions

Food Allergy

Keywords

Prick test; Skin test; Trophallergen; Food sample; Fresh; Frozen; Fruit; vegetables; Meat; Alpha-gal; Arachide; Leguminous plant; Milk; Nuts; Fish; Seafood

Outcome Measures

Primary Outcomes (1)

• Average diameter (mm) of the resulting papules obtained from PT performed with fresh foods, with preserved foods at different storage durations and with positives and negatives controls.

  Average diameter of the papule : average between the smallest diameter and the largest diameter of the papule. Test interpretable if the average diameter of the positive histamine control papule is 3 mm or more and if the average diameter of the negative saline control papule is less than 3 mm. Test considered positive if the average diameter of the papule obtained with the allergen is 3 mm or more and/or half or more of the size of the positive control papule. Test considered negative if the average diameter of the papule obtained with the allergen is less than 3 mm.

  The tests are read 15 to 20 minutes after the food is pricked onto the participants' skin

Secondary Outcomes (1)

• The Histamine Equivalent Prick index diameter (HEP-index diameter) calculated during PT performed with fresh foods and foods stored for different durations

  The tests are read 15 to 20 minutes after the food is pricked onto the participants' skin.

Study Arms (1)

Food allergies arm

EXPERIMENTAL

The participants are their own control. Performing all tests in a single session avoid analysis biases related to intra-individual variability in reactivity encountered during prick-tests performed on various dates (patient included only once in the study, no possible re-inclusion).

Diagnostic Test: Prick-test

Interventions

Prick-test DIAGNOSTIC_TEST

Several foods may be tested for the same participant depending on the number of food allergies the patient has. PT are performed using the "prick-to-prick" method with lancets, in a single session per patient, using fresh and preserved native foods. Simultaneously, a positive control and a negative control are performed. The PT are performed and read by nursing or medical staff trained in the technique. Participants' clinical follow-up is performed continuously for 30 minutes from the performance of the prick-tests and under the responsibility of the allergologist doctor, whose presence is mandatory during the performance of these tests. For meat, fruit, vegetable, leguminous plant, milk, seafood and fish tests will be performed with fresh products and with products preserved for 3 months as well as with products preserved for 6 months \[-15 days; +15 days\]. For dry foods (nuts and peanuts), tests will be performed with products harvested over 3 separate and consecutive seasons.

Food allergies arm

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged 18 and over.
• Having a diagnosis of food allergy(ies) due to one or more of the food allergen studied, previously made by an allergologist, of grade 2 to 3 according to the Ring and Messmer classification.
• Having given consent to participate in the study.
• The diagnosis is made by the allergologist of the department due to the presence of a compatible clinical history implicating the tested allergen, the presence of evidence of sensitization to the allergen (positive prick-test and/or positive specific IgE assays), or even a positive oral allergen reintroduction test.

You may not qualify if:

• Anaphylactic reaction dating less than 6 weeks
• Hospitalization for asthma in the past 3 months
• History of grade 4 anaphylactic reaction according to the Ring and Messmer classification.
• Systemic antihistamine treatment in the 7 days preceding the test
• Systemic beta-blocker treatment on the day of the test.
• Protected person (under guardianship or curatorship)
• Person under judicial supervision
• Persons deprived of liberty
• Person not affiliated with a social security insurance
• Pregnant or breastfeeding women

Sponsors & Collaborators

• Centre Hospitalier Régional d'Orléans: lead

Study Sites (1)

Centre Hospitalier Universitaire d'Orléans

Orléans, 45067, France

RECRUITING

Related Publications (17)

• Santos AF, Riggioni C, Agache I, Akdis CA, Akdis M, Alvarez-Perea A, Alvaro-Lozano M, Ballmer-Weber B, Barni S, Beyer K, Bindslev-Jensen C, Brough HA, Buyuktiryaki B, Chu D, Del Giacco S, Dunn-Galvin A, Eberlein B, Ebisawa M, Eigenmann P, Eiwegger T, Feeney M, Fernandez-Rivas M, Fisher HR, Fleischer DM, Giovannini M, Gray C, Hoffmann-Sommergruber K, Halken S, Hourihane JO, Jones CJ, Jutel M, Knol E, Konstantinou GN, Lack G, Lau S, Marques Mejias A, Marchisotto MJ, Meyer R, Mortz CG, Moya B, Muraro A, Nilsson C, Lopes de Oliveira LC, O'Mahony L, Papadopoulos NG, Perrett K, Peters RL, Podesta M, Poulsen LK, Roberts G, Sampson HA, Schwarze J, Smith P, Tham EH, Untersmayr E, Van Ree R, Venter C, Vickery BP, Vlieg-Boerstra B, Werfel T, Worm M, Du Toit G, Skypala I. EAACI guidelines on the diagnosis of IgE-mediated food allergy. Allergy. 2023 Dec;78(12):3057-3076. doi: 10.1111/all.15902. Epub 2023 Oct 10.

  PMID: 37815205 BACKGROUND

• Riggioni C, Ricci C, Moya B, Wong D, van Goor E, Bartha I, Buyuktiryaki B, Giovannini M, Jayasinghe S, Jaumdally H, Marques-Mejias A, Piletta-Zanin A, Berbenyuk A, Andreeva M, Levina D, Iakovleva E, Roberts G, Chu D, Peters R, du Toit G, Skypala I, Santos AF. Systematic review and meta-analyses on the accuracy of diagnostic tests for IgE-mediated food allergy. Allergy. 2024 Feb;79(2):324-352. doi: 10.1111/all.15939. Epub 2023 Nov 27.

  PMID: 38009299 BACKGROUND

• Henzgen M, Ballmer-Weber BK, Erdmann S, Fuchs T, Kleine-Tebbe J, Lepp U, Niggemann B, Raithel M, Reese I, Saloga J, Vieths S, Zuberbier T, Werfel T; German Society of Allergology and Clinical Immunology (DGAKI); Physicians' Association of German Allergologists (ADA); Society of Pediatric Allergology (GPA); Swiss Society of Allergology. Skin testing with food allergens. Guideline of the German Society of Allergology and Clinical Immunology (DGAKI), the Physicians' Association of German Allergologists (ADA) and the Society of Pediatric Allergology (GPA) together with the Swiss Society of Allergology. J Dtsch Dermatol Ges. 2008 Nov;6(11):983-8. doi: 10.1111/j.1610-0387.2008.06889.x. English, German.

  PMID: 18992038 BACKGROUND

• Rance F, Juchet A, Bremont F, Dutau G. Correlations between skin prick tests using commercial extracts and fresh foods, specific IgE, and food challenges. Allergy. 1997 Oct;52(10):1031-5. doi: 10.1111/j.1398-9995.1997.tb02427.x.

  PMID: 9360758 BACKGROUND

• Brockow K, Romano A, Blanca M, Ring J, Pichler W, Demoly P. General considerations for skin test procedures in the diagnosis of drug hypersensitivity. Allergy. 2002 Jan;57(1):45-51. No abstract available.

  PMID: 11991289 BACKGROUND

• Ruethers T, Johnston EB, Karnaneedi S, Nie S, Nugraha R, Taki AC, Kamath SD, Williamson NA, Mehr SS, Campbell DE, Lopata AL. Commercial shellfish skin prick test extracts show critical variability in allergen repertoire. Allergy. 2023 Dec;78(12):3261-3265. doi: 10.1111/all.15853. Epub 2023 Aug 21. No abstract available.

  PMID: 37602511 BACKGROUND

• Patti ML, De Rose C, Brancato F, Gambacorta A, Miceli Sopo S. Sensitivity of prick test with walnut commercial extracts and of prick by prick with raw walnut compared with open food challenge in walnut allergy. Acta Biomed. 2021 Apr 30;92(S1):e2021067. doi: 10.23750/abm.v92iS1.10043.

  PMID: 33944826 BACKGROUND

• Codreanu F, Moneret-Vautrin DA, Morisset M, Guenard L, Rance F, Kanny G, Lemerdy P. The risk of systemic reactions to skin prick-tests using food allergens: CICBAA data and literature review. Eur Ann Allergy Clin Immunol. 2006 Feb;38(2):52-4.

  PMID: 16711536 BACKGROUND

• Lee S, Jo K, Jeong HG, Choi YS, Kyoung H, Jung S. Freezing-induced denaturation of myofibrillar proteins in frozen meat. Crit Rev Food Sci Nutr. 2024;64(5):1385-1402. doi: 10.1080/10408398.2022.2116557. Epub 2022 Sep 2.

  PMID: 36052640 BACKGROUND

• Garriga T, Guilarte M, Luengo O, Guillen M, Labrador-Horrillo M, Fadeeva T, Sala A, Cardona V. Frozen fruit skin prick test for the diagnosis of fruit allergy. Asian Pac J Allergy Immunol. 2010 Dec;28(4):275-8.

  PMID: 21337912 BACKGROUND

• Terlouw S, van Boven FE, Borsboom-van Zonneveld M, de Graaf-In 't Veld T, Gerth van Wijk R, van Daele PLA, van Maaren MS, Kuijpers JHSAM, Veenbergen S, de Jong NW. Comparison of skin prick test and prick-to-prick test with fruits and vegetables in the diagnosis of food allergy. Clin Transl Allergy. 2024 Jul;14(7):e12375. doi: 10.1002/clt2.12375.

  PMID: 38970153 BACKGROUND

• Begin P, Des Roches A, Nguyen M, Masse MS, Paradis J, Paradis L. Freezing does not alter antigenic properties of fresh fruits for skin testing in patients with birch tree pollen-induced oral allergy syndrome. J Allergy Clin Immunol. 2011 Jun;127(6):1624-6.e3. doi: 10.1016/j.jaci.2011.01.028. Epub 2011 Mar 16. No abstract available.

  PMID: 21411128 BACKGROUND

• van der Valk JP, Gerth van Wijk R, Hoorn E, Groenendijk L, Groenendijk IM, de Jong NW. Measurement and interpretation of skin prick test results. Clin Transl Allergy. 2016 Feb 23;6:8. doi: 10.1186/s13601-016-0092-0. eCollection 2015.

  PMID: 26909142 BACKGROUND

• Warren CM, Sehgal S, Sicherer SH, Gupta RS. Epidemiology and the Growing Epidemic of Food Allergy in Children and Adults Across the Globe. Curr Allergy Asthma Rep. 2024 Mar;24(3):95-106. doi: 10.1007/s11882-023-01120-y. Epub 2024 Jan 12.

  PMID: 38214821 BACKGROUND

• Dribin TE, Motosue MS, Campbell RL. Overview of Allergy and Anaphylaxis. Emerg Med Clin North Am. 2022 Feb;40(1):1-17. doi: 10.1016/j.emc.2021.08.007. Epub 2021 Oct 29.

  PMID: 34782082 BACKGROUND

• Pax AP, Ong L, Pax RA, Vongsvivut J, Tobin MJ, Kentish SE, Gras SL. Industrial freezing and tempering for optimal functional properties in thawed Mozzarella cheese. Food Chem. 2023 Mar 30;405(Pt B):134933. doi: 10.1016/j.foodchem.2022.134933. Epub 2022 Nov 12.

  PMID: 36410214 BACKGROUND

• Bao Y, Ertbjerg P, Estevez M, Yuan L, Gao R. Freezing of meat and aquatic food: Underlying mechanisms and implications on protein oxidation. Compr Rev Food Sci Food Saf. 2021 Nov;20(6):5548-5569. doi: 10.1111/1541-4337.12841. Epub 2021 Sep 25.

  PMID: 34564951 BACKGROUND

MeSH Terms

Conditions

Food Hypersensitivity

Interventions

Patch Tests

Condition Hierarchy (Ancestors)

Hypersensitivity, Immediate; Hypersensitivity; Immune System Diseases

Intervention Hierarchy (Ancestors)

Skin Tests; Immunologic Tests; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Investigative Techniques; Immunologic Techniques

Central Study Contacts

Minaxi Dr PATEL, PhD

CONTACT

238613223; minaxi.patel@chu-orleans.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Masking Details: In the context of the study, one person will perform the PT, and a second person, blinded, will read the tests. This second person will not know the order of the PT performed (fresh food versus preserved food).
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Participants are recruited, day by day, according to the modalities and eligibility criteria during consultations or day hospitalizations in the allergology department of Orléans University Hospital for the follow-up of their food allergy. All participants present one or more food allergy(ies) followed at Orléans University Hospital and agree to participate in the TROPHAPRICK study. If a potential patient attends a consultation without their native foods, the investigator will not include them in the study. However, they may participate in the study during a subsequent follow-up consultation with the investigator (if recruitment is still ongoing). The duration of the inclusion period is maximum 30 months (upon inclusion of the 100th patient) Each participant follow-up duration is 30 minutes (maximum 1 hour) The total research duration is 30 months maximum. The end of the study is defined as the date of the last visit of the last patient.

Study Record Dates

• First Submitted: March 7, 2025
• First Posted: March 12, 2025
• Study Start: April 10, 2025
• Primary Completion (Estimated): October 10, 2027
• Study Completion (Estimated): October 10, 2027
• Last Updated: December 30, 2025

Record last verified: 2025-12

Locations

FR (1)