Allergy to pine pollen is not common. It can become relevant in areas with high concentrations, for example in the Basque Country and Galicia.
Symptoms can be nasal, ocular or bronchial. Generally, the patient is monosensitive, that is, he has no allergy to other pollens.
What is the pine processionary caterpillar?
The processionary caterpillar is an insect that lives in pine trees and has 4 stages of development: moth, egg, larva and chrysalis. It receives the name of processionary because they parade as in a procession.
In their larval phase they have microscopic hairs whose function is to defend against possible predators. In the mature phase, after leaving the pine trees, the caterpillar can releases up to more than 1 million of these hairs
What are the symptoms produced by the pine processionary caterpillar?
More frequently, it causes itching and skin lesions in exposed areas (arms, legs and face) due to the penetration of the hairs. In children, injuries to the palms of the hands are typical because they try to catch the caterpillars.
Injuries can be:
-Dermatitis with scratching lesions and eczema.
-Contact urticaria which may be associated with angioedema of the eyelids.
-Less frequently, lesions such as vesicles or pustules.
It can also produce ocular symptoms such as conjunctivitis or keratitis.
Respiratory symptoms are less frequent, which can be associated with anaphylaxis.
Why do the symptoms occur?
The mechanism involved in the production of this reaction is usually mechanical or irritative, although it is sometimes produced by an IgE-mediated mechanism.
Who can affect?
It can produce symptoms in anyone who has been exposed to pine forest areas.
It has also been described as an occupational disease in resin collectors, lumberjacks, farmers or ranchers, due to their high exposure to caterpillars.
How can symptoms be treated?
If you present the symptoms described, you should request an assessment by your allergy specialist and the case will be evaluated.
Treatment is symptomatic according to the clinical picture: oral antihistamines, topical or oral corticosteroids. And in severe cases (anaphylaxis) it will be necessary to use adrenaline.
Do you have any doubt?
Dr Jaritzy Negrín González
Especialista en Alergología.