Measurement of IgE antibodies to shrimp tropomyosin is superior to skin prick testing with commercial extract and measurement of IgE to shrimp for predicting clinically relevant allergic reactions after shrimp ingestion

• Published in: Journal of allergy and clinical immunology Vol. 125; no. 4; pp. 872 - 878
• Main Authors: Yang, Ariana C., MD, PhD, Arruda, L. Karla, MD, PhD, Santos, Ana Beatriz R., PhD, Barbosa, Michelle C.R., MSc, Chapman, Martin D., PhD, Galvão, Clóvis E.S., MD, PhD, Kalil, Jorge, MD, PhD, Morato-Castro, Fábio F., MD, PhD
• Format: Journal Article
• Language: English
• Published: New York, NY Mosby, Inc 01-04-2010; Elsevier; Elsevier Limited
• Subjects: Adolescent; Adult; Allergens - immunology; Allergic diseases; Allergies; Allergy and Immunology; Animals; Antibody Specificity; Biological and medical sciences; Digestive allergic diseases; Female; Food; Food allergies; Food allergy; food challenge; Food Hypersensitivity - diagnosis; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Hypersensitivity - diagnosis; Immunoglobulin E - blood; Immunopathology; Male; Medical sciences; Middle Aged; Penaeidae - classification; Penaeidae - immunology; Predictive Value of Tests; Sarcoidosis. Granulomatous diseases of unproved etiology. Connective tissue diseases. Elastic tissue diseases. Vasculitis; Sensitivity and Specificity; shrimp; skin prick test; Skin Tests; specific IgE; Studies; tropomyosin; Tropomyosin - immunology; Young Adult; Food allergy; Double-blind, placebo-controlled food challenge; shrimp; Negative predictive value; specific IgE; food challenge; tropomyosin; NPV; SPT; PPV; skin prick test; Positive predictive value; DBPCFC; Immunopathology; Prick test; Specific IgE; Antibody; Tropomyosin; Exploration; Extract; Macrura; Ingestion; Crustacea; Immunology; Arthropoda; Digestive diseases; Decapoda; Invertebrata; Shrimp; Skin test; Provocation test
• ISSN: 0091-6749; 1097-6825
• DOI: 10.1016/j.jaci.2009.11.043

Background Shrimp is a frequent cause of food allergy. Tropomyosin is the major allergen in shrimp, and it shares homology to tropomyosins from other crustaceans, dust mites, cockroach, and parasites. Objective The aim of this study was to determine the value of detection of IgE to shrimp tropomyosin in the diagnosis of shrimp allergy. Methods We have studied 35 patients with asthma, rhinitis, or both who were sensitized to Dermatophagoides pteronyssinus . All subjects underwent skin prick testing in addition to double-blind, placebo-controlled food challenges (DBPCFC); oral open challenges; or both with shrimp. Measurements of IgE to shrimp and shrimp tropomyosin were carried out by means of CAP and chimeric ELISA, respectively. Results Oral challenges confirmed the diagnosis of shrimp allergy in 7 patients. IgE measurement to shrimp tropomyosin was positive in 71.4% of the patients with shrimp allergy. Of the 28 patients without shrimp allergy, only 7.1% (2/28) had IgE to shrimp tropomyosin compared with 25% (7/28) who had IgE to shrimp and 35.7% (10/28) who had positive skin prick test responses to shrimp. Sensitivity was similar for all 3 methods (71.4%); in contrast, specificity of IgE to shrimp tropomyosin (92.8%) was greater than that of IgE to shrimp (75%) and skin prick testing (64.2%). With regard to diagnostic efficiency, measurement of IgE to shrimp tropomyosin was superior to measurement of IgE to shrimp and skin prick testing (88.5%, 74.2%, and 65.7%, respectively). Conclusion Use of measurements of IgE to shrimp tropomyosin provided added value to the diagnosis of shrimp allergy.