[Giardia lamblia extract (giardine): its immunologic mechanism].

Giardia lamblia is a protozoa that invades the high portions of human small bowel, as well the gall bladder and biliary passages. The absorption from the gut of extrinsic particles which have all properties occurs at full scale in the small bowel. Infections by this protozoa may lead to different clinical symptoms: departing free-symptom, urticarial manifestations of variable intensity and malabsorption syndromes, as well. In Cuba, Giardia lamblia parasitism constitutes a health problem because of its high incidence and prevalence. Investigators have showed allergic dermatological disorders and others, in patients with giardiasis, that may obey from two mechanisms: first, the parasite or its metabolic products might be antigenic for the host; second, the parasite may act as a hapten, that in successive sensitizations might lead to such manifestations, producing specific antibodies which have been found in patients' sera with giardiasis. We recently have elaborated an allergenic extract from Giardia lamblia (we called it giardine ), for demonstrating cutaneous sensitization to such protozoa. In other way, Prausnitz and Küstner, in 1921, showed that a dermal allergic reaction could be passively transferred by means of sensitized patient's serum to a non-sensitized subject. More recently, in 1967, Ishizaka and Ishizaka and Johansson and Benich, in separate studies, showed that skin sensitizing antibodies belonged to a different kind of immunoglobulin, IgE, and it could be measured in serum from sensitized patients. So, a study of sensitization to Giardia lamblia has been performed. Twenty-two patients have been studied suffering from giardiasis with at least 3 month evolution of this disease.(ABSTRACT TRUNCATED AT 250 WORDS)