Insect Venom Allergy

A picnic outside?

Lunch on the terrace?

Sounds tempting – but the risk of getting stung by a wasp is high.

Introduction

Walking barefoot in the grass, feeling free – a sting by a honeybee can suddenly dampen the fun. For most of us, pain and swelling after insect stings pass quickly with rapid cooling or by reducing the itching. The sting reaction manifests as a local reaction. However, three percent of the population suffers from systemic reactions after insect stings (1).

Symptoms

The clinical presentation thereby ranges from mild to life-threatening, can affect different organs and includes generalized swelling and itching, urticaria, angioedema, diarrhea, vomiting, chest tightness, shortness of breath with swelling of the throat and bronchospasm. One of the most severe manifestation of allergy is the anaphylactic shock, which is most often triggered by insect venom and can be fatal. Approximately 200 deaths due to insect venom allergy occur in Europe every year, and it is likely that additional deaths are not recognized and therefore not reported (1).

Culprit Insects

The insects most frequently causing severe allergic reactions belong to the order Hymenoptera. In Europe the family of Apidae (honeybee, Apis mellifera) and Vespidae (wasp, Vespula vulgaris, Vespula germanica) and the paper wasp (Polistes dominulus) are the most prevalent.

Diagnostic tools

A proper diagnostic work up includes a thorough anamnesis, skin testing and blood testing for bee- and wasp venom specific IgE antibodies. As venom extracts contain several allergens with CCD (cross-reactive carbohydrate) epitopes (e.g., Api m 1, Ves v 2), extract-based test results are often misleading due to double positivity (in approx. 50% of cases). To completely avoid CCD interference in serological tests, blocking of CCD specific antibodies and the use of molecular allergens is essential.

Molecular allergens

Several molecular allergens are available for routine testing. Among these, the species-specific molecular allergens from bee (Api m 1 and Api m 10) and wasp venom (Ves v 1 and Ves v 5) are the most prevalent. These allow to determine whether a patient is sensitized only to bee-, wasp- or to both venoms (2). This is essential for the selection of the correct venom for allergen-specific immunotherapy (AIT), which is the only available causal treatment with a very high efficacy.

ALEX contains:

  • Bee venom extract

  • Bee venom allergen Api m 1 (Phospholipase A2)

  • Bee venom allergen Api m 10 (Icarapin)

  • Wasp venom extract (Vespula vulgaris)

  • Wasp venom allergen Ves v 1 (Phospholipase A1)

  • Wasp venom allergen Ves v 5 (Antigen 5)

  • Wasp venom extract (Polistes dominulus)

  • Wasp venom allergen Pol d 5 (Antigen 5)

  • Integrated CCD blocking capability

References

  1. doi: 10.18176/jiaci.0310
  2. doi: 10.1371/journal.pone.0199250