Tropomyosin in shrimp rPen a 1 IgE, f351
Shrimp is considered a highly allergenic food, causing severe reactions such as anaphylaxis. Pen a 1 (tropomyosin) is responsible for cross-reactivity in members of the shellfish family, especially crustaceans (such as shrimp, crab and lobster).
Allergy component diagnosis is based on the detection of sensitization to allergens at the molecular level using natural highly purified and recombinant allergen molecules, i.e. their individual allergy components.
There are 3 main advantages of performing this analysis:
- Allergy component diagnostics gives the ability to differentiate true sensitization from sensitization due to cross-reactivity. This data will help to identify the sources of allergy: one single allergy, several closely related allergies, or many different allergies.
- Molecular allergodiagnosis eliminates the need for provocation tests and allows for clearer recommendations regarding the elimination of contact with allergens.
- Molecular allergodiagnostics is necessary in the selection of ASIT, in persons with polyvalent (multiple) sensitization it is the most accurate way to determine the most important allergen for which therapy will be carried out.
The allergenic substance includes not one but several protein components that can act as allergens:
Major allergic components are the major allergenic molecules, antibodies to which are found in more than half to 50% of patients in the population reacting to a given source. They are heat stable and more immunogenic. Major are large in size and are found in greater quantities in a given allergen.
Minor allergens are minor, smaller in size and less immunogenic allergenic molecules that are usually contained in smaller amounts within an allergen but are present in many different allergens, sometimes not closely related, providing cross-allergy. That is, allergens with a prevalence of more than 50% are called major allergens and less than 10% are called minor allergens.
The prevalence of shellfish allergy ranges from 1.3% to 5.2% depending on different dietary habits in different countries. Asians are reported to have a higher prevalence of shellfish allergy compared to people in western countries due to higher consumption of shellfish in this region.
Shrimp allergy is primarily due to consumption of shrimp meat and secondarily due to interpromotion with shrimp and their products in the food industry and inhalation of aeroallergens from shrimp processing.
Exposure of a sensitized person to shrimp can cause anaphylaxis, skin symptoms, urticaria and angioedema, gastrointestinal symptoms, and respiratory symptoms (rhinitis and occupational asthma).
The shrimp allergen is present in its abdominal and tail muscles. In addition, shellfish allergy has been found to be less common in children than in adults.
People with hypersensitivity are advised to avoid consumption of shrimp meat and contact with shrimp meat (handling) to prevent allergic reactions.