An Allergy Profile (Insects) Blood Test is used to detect allergic reactions to insect stings or bites by measuring IgE antibodies in the blood. Insect allergies, particularly to stings from certain species like bees, wasps, hornets, and ants, can cause severe allergic reactions, including anaphylaxis. This blood test helps to identify which specific insect venom the person is allergic to and guides management and treatment.
Purpose of an Insect Allergy Blood Test
- To identify IgE-mediated allergic reactions to specific insect venoms.
- To help determine which insect (e.g., bee, wasp, hornet, ant) is causing allergic reactions.
- To guide treatment, including allergen immunotherapy (venom immunotherapy) for people with severe insect sting allergies.
Types of Insect Allergy Blood Tests
- Specific IgE Testing for Insect Venom:
- Measures the amount of IgE antibodies in the blood against the venom of specific insects.
- Common venoms tested include:
- Common Wasp – Yellow Jacket
- Bee
- Paper Wasp
- Yellow Hornet
- White Faced Hornet
- A positive result indicates that the immune system has produced IgE antibodies in response to a specific insect’s venom, suggesting an allergy.
- Component-Resolved Diagnostics (CRD):
- A more detailed approach that analyzes individual protein components in the venom. This helps in understanding which specific protein in the venom is causing the allergic reaction.
- CRD is particularly useful in differentiating between allergies to different wasp or bee species, which can help in tailoring venom immunotherapy.
- Total IgE Testing:
- Measures the overall level of IgE in the blood. This test may indicate a general allergic tendency but does not specify the allergen.
- It’s often used in conjunction with specific IgE testing to understand the patient’s allergic profile.
Testing Procedure
- A blood sample is collected and analysed for the presence of IgE antibodies to insect venom.
- Results are typically given as numerical values, with higher levels indicating a greater likelihood of an allergy.
Interpreting Results
- Class 0: No detectable specific IgE; unlikely to be allergic to the tested insect venom.
- Class 1-6: Increasing levels of specific IgE, with Class 6 representing the highest level of sensitivity and greatest likelihood of a severe allergic reaction.
Symptoms of Insect Allergies
- Mild reactions may include localised swelling, itching, and redness.
- Severe reactions (anaphylaxis) may include difficulty breathing, hives, swelling of the face and throat, dizziness, rapid pulse, or even loss of consciousness.
Diagnosis and Management
- Venom Immunotherapy (VIT):
- If a person is diagnosed with a severe allergy to insect venom, venom immunotherapy may be recommended.
- This involves administering small, increasing doses of the insect venom over time to desensitize the immune system and reduce the severity of future reactions.
- Emergency Preparedness:
- Patients with confirmed insect allergies, especially those at risk for anaphylaxis, should carry an epinephrine auto-injector (EpiPen) and have an action plan in place in case of a sting.
- Avoidance and Precaution:
- Insect avoidance strategies, such as avoiding areas with known insect nests, wearing protective clothing, and being cautious around outdoor areas, are essential for reducing the risk of stings.
- Oral Challenge Test (if necessary):
- In rare cases where the diagnosis is unclear, a supervised sting challenge may be performed to confirm the allergy.
When is Insect Allergy Blood Testing Recommended?
- After experiencing symptoms of an allergic reaction following an insect sting, such as swelling, hives, or anaphylaxis.
- To determine if venom immunotherapy is needed to prevent future reactions.
- In cases where the person has a history of severe reactions but is unsure of the specific insect involved.
The Allergy Profile (Insects) Blood Test is an essential tool for diagnosing insect venom allergies and ensuring the proper management and prevention of severe reactions, including life-threatening anaphylaxis. Consulting with an allergist is crucial for interpreting the test results and creating a personalised treatment plan.
Results – 2 days from Laboratory receiving sample