Venom immunotherapy reduces large local reactions to insect stings

Large local reactions to insect stings cause significant morbidity and impair quality of life. Venom immunotherapy is not recommended because of a low risk for future systemic reaction and unproven efficacy in preventing large local reactions.


Figure 1. Mind map of insect venom allergy (click to enlarge the image).

Reaction to Wasp	Reaction to Bee
More common	Rarer
After a single sting	After many stings
Typical narrow waist and little hair	Hairy "fuzzy" bee

Table 1. Comparison of allergic reactions to wasp and bee venom.


Figure 2. A yellow jacket wasp with a typical narrow waist (left) and a honey bee with a fat hairy "fuzzy" body (right). Image source: Wikipedia 1, 2, GNU Free Documentation License.

In this study, a sting challenge in 41 patients with previous large local reactions and positive venom skin tests caused large local reactions 16 cm or larger in 34 patients, and 29 consented to treatment. Venom immunotherapy was initiated in 19, and 10 were untreated controls. Sting challenge was repeated after 7 to 11 weeks, and annually for as long as 4 years.

After 7 to 11 weeks of treatment, the size and duration of large local reactions decreased 42% and 53%, respectively, in treated patients and 18% in controls (P lower than 0.01 for both). The response was similar after 1 year, and improved after 2 to 4 years to 60% and 70%, respectively.

The authors concluded that venom immunotherapy significantly reduced the size and duration of the large local reactions, and the efficacy improved over a period of 2 to 4 years of treatment.

References:

Venom immunotherapy reduces large local reactions to insect stings. David B.K. Golden et al. JACI, Volume 123, Issue 6, Pages 1371-1375 (June 2009).
Venom Allergy: A Short Review. V. Dimov, 08/2007.
Challenge sting: to bee or not to bee? Sting challenges don't add much to current diagnostic testing & increase risk http://goo.gl/F50dX
Image source: Wikipedia, GNU Free Documentation License.