Background: Intestinal parasites stimulate IgE synthesis by their proteinases. Because of their ability to induce IgE production and mast cell degranulation (either directly, e.g. Ascaris, or via specific IgE) it is possible that some parasites induce allergic manifestations. Some parasites may be more allergenic than others due to their allergenicity. Genetic predisposition, nutritional status, and psychosocial variables of the host and the time and degree of allergen exposure may also play an important role.
The aim: Of our study was to investigate which parasites are more frequently related to the skin manifestations and if atopic background of the host has a role in these skin allergic hives in intestinal parasites.
Material and method: 55 patients (13 men, mean age 36 years old) infested with digestive parasites were skin prick tested to inhalant allergens (house dust mites, pollens, animal dander) in order to evaluate the atopic status. All patients had allergic skin manifestations (rash and hives) and angioedema due to their intestinal parasites, which remitted after antiparasitic treatment.
Results: Forty (73.3%) patients presented angioedema and 15 patients (26.6%) had chronic rash. Patients who were infected with Ascaris had more severe symptoms: more than 2/3 had angioedema, and only one third had chronic rash. More than 2/3 of the patients were infested with Ascaris lumbricoides: 38 patients (69.09%), and only one third were infested with Giardia lamblia: 18 patients (32.72%). Only one third of the patients (17-30.9%) had positive skin prick tests for at least one inhalant allergen.
Conclusions: The parasite most frequently implicated in skin allergic manifestations in our region is Ascaris lumbricoides. Acute angioedema or chronic rash are the major skin manifestations in parasitic infestation. The atopic trait has no importance in the appearance of allergic manifestations in parasitic infestation.