Allergy to insect stings: specific immunotherapy protects long-term

A significant proportion of children keep their Hymenoptera venom allergy growing and immunotherapy reduces the risk of new generalized even 10 to 20 years after the end of treatment response, shows a study published Thursday in the " New England Journal of Medicine "(NEJM).

Children are supposed to lose their growing Hymenoptera venom allergy (bees, wasps, hornets, ants), but there is relatively little data. Specific immunotherapy with Hymenoptera venoms and other insects that has proven its effectiveness, is for children who have had a severe generalized reaction to an insect bite.

Dr. David Golden and his colleagues at Johns Hopkins Asthma and Allergy Center, Baltimore (Maryland) wanted to check first if the loss of growing allergy is common among children and secondly to study the effectiveness long-term specific immunotherapy in children.

For this, they have made monitoring a study they published in 1990 in the NEJM on the value of specific immunotherapy in children with an allergic reaction to an insect bite between 1978 and 1985.

On 512 patients who responded to the follow-up survey (between 1997 and 2000), with a decline of 18 years on average compared to the first reaction, 163 had been treated with immunotherapy for 3.5 years. More than 40% of respondents were transplanted between 1987 and 1999.

The results show that while the majority of children lose their sensitivity to insect bites, an allergic reaction still occurs in nearly one in five children in a sting, which could occur for some up to 32 years after the first reaction.

The frequency of allergic reactions in untreated children decreased slowly over time, but more than 20 years after the first reaction she was still 13%. "Therefore, for many children, this allergy does not disappear growing," the authors write.

Furthermore, this study shows that even long after the cessation of desensitization, processing continues to take effect. Generalized reactions were very significantly less frequent in children treated (3%) than in untreated children (17%).

Reducing the risk of systemic reaction obtained with desensitization was even greater for children whose first reaction was moderate to severe (respiratory disorders, hypotension), the frequency of severe reactions was 32% in untreated children against 5% in those who were treated.

For those who had been treated for mild generalized reactions (skin only events), none of the 21 who were transplanted has been widespread reaction.

The authors recommend specific immunotherapy with Hymenoptera venoms for children with moderate to severe reactions, but not for those who have mild reactions. Moreover, the treatment may be prolonged in children with very severe reactions, they say.

In an accompanying editorial, Rebecca Gruchalla of the University of Texas Southwestern Medical Center in Dallas agrees with these recommendations and hopes that these new data will help doctors to convince parents of the value of treatment in children most at risk.