Usefulness of the Allergen Specific Nasal Provocation Test in the Diagnosis of Shellfish Allergy
Gelis S1, Rueda M2, Pascal M3,4, Fernández-Caldas E5,6, Abel Fernández E5, Araujo-Sánchez G1, Bartra J1,4, Valero A1
1Department of Pneumology and Allergy, Hospital Clínic. Institut d’Investigacions Biomèdiques Agustí Pi I Sunyer (IDIBAPS). Universitat de Barcelona. Barcelona, Spain
2Allergology Department, Hospital Quirónsalud, Barcelona, Spain
3Immunology Department, Hospital Clínic, Institut d’Investigacions Biomèrdiques Agustí Pi I Sunyer (IDIBAPS). Universitat de Barcelona. Barcelona, Spain
4RETICS ARADyAL Network, Instituto de Salud Carlos III, Spain
5Immunotek SL, Madrid, Spain
6University of South Florida College of Medicine, Tampa, Florida, USA
J Investig Allergol Clin Immunol 2022; Vol. 32(6)
Background: Shellfish allergy is an important cause of food allergy and anaphylaxis worldwide. Several allergenic proteins have been described in the last few years, but the only diagnostic tool that allows discrimination between allergic and non-allergic sensitized subjects is still the oral food challenge (OFC).
Objective: The aim of this study was to evaluate the usefulness of nasal allergen provocation test (NAPT) as a diagnostic tool in the diagnosis of shellfish allergy.
Methods: Forty-five subjects with confirmed sensitization to shrimp by a positive skin prick test (SPT) to a commercial shrimp extract were recruited and classified as Sensitized-Allergic or non-Allergic based on current tolerance to shrimp intake, the result of an OFC with a freeze-dried cooked shrimp mixture extract, or recent history of anaphylaxis from shrimp ingestion. These subjects and ten controls without shrimp sensitization were subjected to a NAPT with a freeze-dried cooked shrimp mixture extract. The response was evaluated by means of acoustic rhinometry (AcRh) and visual analogue scale scores (VAS).
Results: Significant differences (p=.001) were found between the Sensitized-Allergic group (18/20 positive NAPT, 90%) compared to both Sensitized-non-Allergic (2/18 positive NAPT, 11.1%) and Control (0/10 positive NAPT) groups. NAPT allows differentiation between allergic and non-allergic subjects with a S: 90%, E: 89%, PPV: 90% and NPV: 89%.
Conclusions: According to the study results NAPT may be a useful diagnostic tool that allows differentiating sensitized symptomatic subjects from sensitized tolerant. It could be a valuable test to consider when conducting a shrimp allergy study.
Key words: Nasal allergen provocation test, Nasal allergen challenge, Acoustic rhinometry, Oral food challenge, Shellfish allergy, Shrimp allergy