[A study comparing the clinical phenotypes of fish-allergic patients with their specific IgE profiles to fish parvalbumin, enolase, aldolase and gelatin].
- Molecular and Translational Allergology
The aim of this study was to investigate the added value of using a panel of fish allergens in component-resolved diagnosis of fish-allergic patients.
Patients and methods
Sixty-two patients were diagnosed as being allergic to fish by clinical history and with positive skin prick-tests and specific IgE to fish extracts (cod, salmon and tuna). Allergen-specific IgE levels to fish parvalbumin, enolase, aldolase and gelatin were quantified by Elisa.
Forty-five of the patients were sensitized to parvalbumin. Among the cod parvalbumin-sensitized patients, 50% were also sensitized to both enolase and aldolase. Of the patients with positive skin tests to salmon and to tuna (75.6% and 67.6%, respectively), isolated sensitization to parvalbumin was observed. Mean levels of specific IgE to cod and enolase parvalbumin were positively correlated with the severity of the patients’ clinical symptoms; this was not the case for cod aldolase. Patients were clustered into three groups according to their parvalbumin-specific IgE-reactivity. In the first group, the 36 patients who were sensitized to three different fish reported mild to severe symptoms; their symptoms were correlated with the presence of IgE to total cod extract and to cod parvalbumin. The second group of 9 mono-sensitized patients had only minor symptoms of fish allergy, most often to salmon; their symptoms were positively correlated with specific IgE levels of salmon extract and cod parvalbumin-specific IgE. The third group consisted of 17 patients who were sensitized to a small number of fish; they had moderate to severe symptoms. While this group of patients had no detectable parvalbumin-specific IgE, 70.6% of them were found to have IgE specific for fish aldolase, enolase or gelatin; in this group, the presence of IgE specific for cod was rarely observed.
The use of a panel with a number of allergenic fish proteins may contribute to the improvement of the diagnosis of fish allergy. Specific sensitization profiles appear to be associated with certain profiles of clinical symptoms.