Cutaneous reactions to pine processionary caterpillar (Thaumetopoea pityocampa) in pediatric population

Cutaneous lesions caused by pine processionary caterpillar (Thaumetopoea pityocampa, TP) are frequent in pinewood areas. However, no epidemiological studies have been performed so far in the pediatric population. In this study, we evaluated the relevance of reactions to pine processionary caterpillar in the pediatric population of our environment and determined the possible role of an IgE-mediated mechanism. A questionnaire was developed and given to 1,101 children and adolescents ranging from 3 to 17 years of age from rural areas with large pine forests. A total of 653 questionnaires were answered by the children or their parents. The search for immunoglobulin E (IgE)-mediated cases was based on the presence of a suspected reaction to caterpillar and confirmed by in vivo (skin prick) and in vitro (immunoblotting) tests. Sixty of the 653 people interviewed (9.18%) identified a cutaneous reaction from exposure to the processionary caterpillar. Within this group only four cases (6.7%) were because of an IgE-mediated mechanism. The predominant clinical feature of these patients with allergy to caterpillar was contact urticaria. We present the first study of cutaneous reactions to pine processionary caterpillar in a large pediatric population. This is a frequent pathology in pinery zones and only in a minority of the cases are because of an IgE-mediated allergic mechanism. This fact contrasts with studies in adults, where this percentage is much greater.