Allergy to pigeon tick (Argas reflexus): demonstration of specific IgE-binding components.

BACKGROUND: The European tick, Argas reflexus, is an urban pest parasitizing urban pigeons and may cause a wide range of allergic reactions. METHODS: Specific IgE to A. reflexus, SDS-PAGE and IgE immunoblotting, performed with tick extract, were carried out in the sera of 6 patients who reported allergic reactions after tick bite. RESULTS: Specific IgE to A. reflexus (RAST class ranging from 1 to 3) were detected in the sera of 6 patients who reported allergic reactions (urticaria and angioedema in 2 and anaphylaxis in the other 4 patients) after tick bite. IgE reactivity to two bands of 22 and 40 kDa were identified in the patient sera. CONCLUSIONS: Allergy to A. reflexus has to be considered in allergic patients living in buildings where pigeons have their nests. The powerful sensitizing property of tick allergen is underlined by the observation that none of our patients was atopic.

The allergic march in pollinosis: natural history and therapeutic implications.

BACKGROUND: That specific immunotherapy (SIT) can slow the march of allergy has been confirmed in controlled clinical trials. However, an assessment of its effects in everyday life, in a large cohort of patients, might provide further useful information. METHODS: This observational study comprised 3,643 patients allergic to pollens; 1,620 with pure allergic rhinitis or rhinitis and intermittent or mild-persistent bronchial asthma, responding poorly to standard pharmacological therapy (SPT), were treated for 3 years with SPT alone (pure rhinitis, n = 890), or combined with continuous SIT (rhinitis and asthma, n = 730). Symptom/drug scores were recorded, respiratory function and skin tests were done, and methacholine challenge was scheduled at the beginning and end of the study. A series of 2,023 patients with pure rhinitis, responsive to SPT, were asked to 'self-medicate' as needed, serving as a control group to check the incidence of asthma. RESULTS: The incidence of rhinitis-asthma co-morbidity was highest in the self-medication group (50.8%). Persistent rhinitis was associated with asthma more often than the intermittent form, regardless of the severity of the symptoms that led to progression to asthma in patients with intermittent rhinitis. Treatment with SIT combined with SPT always slowed the allergic march which, however, was not influenced by drugs alone. CONCLUSIONS: In routine clinical practice, SIT is effective in preventing the allergic march. Patients with persistent rhinitis, who are at greatest risk of progression to asthma, appear to be the most logical candidates.