Shrimp Allergy: Analysis of Commercially Available Extracts for In Vivo Diagnosis
Asero R1, Scala E2, Villalta D3, Pravettoni V4, Arena A5, Billeri L6, Colombo G7, Cortellini G8, Cucinelli F9, De Cristofaro ML10, Farioli L11, Iemoli E12, Lodi Rizzini F13, Longo R14, Losappio L15, Macchia D16, Maietta G17, Minale P18, Murzilli F9, Nebiolo F19, Pastorello EA15, Ventura MT20, Voltolini S18, Amato S21, Mistrello G21
1Ambulatorio di Allergologia, Clinica San Carlo, Paderno Dugnano (MI), Italy
2Istituto Dermopatico dell'Immacolata – IRCCS, Roma, Italy
3SSD di Allergologia e Immunologia Clinica, Azienda Ospedaliera S. Maria degli Angeli, Pordenone, Italy
4UOC Clinical Allergy and Immunology, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
5Ambulatorio Allergologia, Azienda Usl 5 di Messina, Messina, Italy
6Department of Laboratory Medicine, University Hospital, Padova, Italy
7Allergy and Clinical Immunology Unit, IRCCS San Raffaele Hospital, Milan, Italy
8UO di Medicina Interna e Reumatologia, Azienda Sanitaria della Romagna, Rimini, Italy
9UOSD di Allergologia, Ospedale SS Filippo e Nicola di Avezzano, Avezzano (AQ), Italy
10Ambulatorio di Allergologia, Ospedale San Timoteo, Termoli (CB), Italy
11Department of Laboratory Medicine, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
12Allergy and Clinical Immunology Unit, ASST Fatebenefratelli/Sacco, Milano, Italy
13SSVD Allergologia, AO Spedali Civili di Brescia, Brescia, Italy
14Ambulatorio Territoriale di Allergologia, ASP Vibo Valentia, Italy
15Department of Allergology and Immunology, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
16Allergologia Immunologia Clinica, PO S Giovanni di Dio, Firenze, Italy
17Ambulatorio di Allergologia Accreditato ASL, Lecce, Italy
18UOC Allergologia IRCCS San Martino-IST, Genova, Italy
19Ambulatorio di Allergologia e Immunologia, AO Ordine Mauriziano, Torino, Italy
20Dipartimento di Medicina Interna, Immunologia e Malattie Infettive, Università di Bari, Policlinico, Bari, Italy
21R & D, Lofarma, Milano, Italy
J Investig Allergol Clin Immunol 2017; Vol 27(3)
Background: Skin prick testing (SPT) with commercial extracts is the first step in the diagnosis of shrimp allergy, although its clinical efficiency is unknown.
Objective: To analyze the clinical usefulness of all commercial crustacean extracts available for SPT in Italy.
Methods: We performed a multicenter study of 157 shrimp-allergic patients who underwent SPT with 5 commercial crustacean extracts and with house dust mite (HDM) extract. Commercial extracts were analyzed using SDS-PAGE and compared with a freshly prepared in-house shrimp extract. IgE to Pen a 1/Pen m 1, Pen m 2, and Pen m 4 was determined, and immunoblot analysis was performed on a large number of sera.
Results: The skin reactions caused by commercial crustacean extracts were extremely heterogeneous, resulting in 32 clinical profiles, with marked differences in protein content and missing proteins at molecular weights corresponding to those of major shrimp allergens. Only strong Pen a 1/Pen m 1 reactors reacted to both HDM and all 5 commercial extracts in SPT. Most patients, including those who were tropomyosin-negative, reacted to HDM. Patients reacted to a large and variable array of proteins, and IgE reactivity was common at high molecular weights (>50 kDa).
Conclusions: The in vivo diagnosis of shrimp allergy must continue to be based on SPT with fresh material. Shrimp-allergic patients frequently react to a number of ill-defined high-molecular-weight allergens, thus leaving currently available materials for component-resolved diagnosis largely insufficient. Mites and crustaceans probably share several allergens other than tropomyosin.
Key words: Allergens, Allergy diagnosis, Food allergy, Shrimp allergy, Skin testing.