Second generation antihistamines in the treatment of seasonal allergic rhinitis due to Parietaria and cypress pollen.

Second generation antihistamines have been employed in the treatment of seasonal allergic rhinitis for many years. However, their effects on two distinctive Mediterranean allergic conditions, viz. Parietaria pollinosis and cypress pollinosis, have been scarcely investigated, so far. A comparative efficacy and side effect trial of astemizole and terfenadine in the treatment of seasonal allergic rhinitis due to either Parietaria or cypress pollen was carried out in 27 adult patients, according to a double-blind, double-dummy parallel-group design. Airborne pollen monitoring allowed comparison of symptom scores with pollen counts. Seven patients (26%) withdrew, due to poor symptom control. In contrast, in a subset of 15 patients who completed the trial, treatment led to a substantial and statistically significant decline in symptom severity in both the astemizole and the terfenadine study group. However, no statistically significant inter-group differences could be detected.

Allergens of Arizona cypress (Cupressus arizonica) pollen: characterization of the pollen extract and identification of the allergenic components.

Species of the Cupressaceae family are an important cause of respiratory allergies in countries with a Mediterranean climate. An allergenic extract from Cupressus arizonica pollen was prepared with two extraction steps followed by ammonium sulfate precipitation, giving a protein yield of about 3%. Cupressus arizonica pollen extract was also characterized by means of sodium dodecylsulfate-polyacrylamide gel electrophoresis, followed by IgE and IgG immunoblotting and lectin blotting. IgE reactivity was restricted to six components, whereas IgG binding showed a more complex pattern. A 43 kd component, predominant both in its intensity and frequency of recognition by human IgE antibodies, was identified as the major allergen of C. arizonica. Four of the six IgE-binding components, including the major allergen, seem to be glycoproteins, as confirmed by the lectin blotting analysis. The extract produced inhouse was used to set up an immunoenzymatic test to evaluate the specific IgE binding in a panel of sera from 33 immunotherapy-free subjects who were monosensitized to cypress pollen. The percent of positivity obtained was much higher than that reported in the literature for commercial immunoassays.

Airborne Cupressaceae pollen in southern Italy.

The allergenic airborne pollen of Cupressaceae was surveyed in the area of Bari (Southern Italy) over an 8-year period (1982-1989). A Burkard 7-day recording volumetric spore trap was used for the aerobiologic investigation. The results showed a notable annual pollinic presence of airborne Cupressaceae pollen, the largest amount recorded in winter and early spring. Remarkable fluctuations of the Cupressaceae pollen counts in a 2-year cycle were also observed. The features of the main pollen season are described. In particular, its duration was found to be on average 45 days. A study of Cupressaceae trees distribution indicated that the most widespread genus was Cupressus, represented in particular by the species Cupressus arizonica Green and Cupressus Sempervirens L. The employment of these trees for reforestation and garden-use has increased considerably in the last 40 years. These findings can also be of interest in other countries where Cupressaceae allergy has been reported, particularly in the Mediterranean basin and in North America.

Changes in skin reactivity, specific IgE and IgG levels after one year of immunotherapy in olive pollinosis.

Changes in specific skin reactivity, specific IgE and specific IgG after immunotherapy (IT) were investigated in olive pollinosis. Thirty patients, receiving IT with commercial extracts, were studied in comparison with a control group of seven patients, receiving only drug therapy. Skin reactivity, IgE and IgG were assessed before starting IT and 1 year later. Definite changes in the three considered parameters occurred in patients given IT with Olea europaea extracts; no variation was observed in the control group. The specific skin reactivity, evaluated by means of quantitative skin prick tests, significantly decreased (Skin Index geometrical mean from 2.73 to 0.88, P less than 0.001); the specific IgE, measured by RAST, were surprisingly decreased (from 7.76 to 4.74 PRU/ml, P less than 0.001); the specific IgG, measured by ELISA, in basic conditions were detectable only in nine patients of 30, while, after IT, they were found in almost all patients with a remarkable increase (from 5.48 to 266.89 AU/ml, P less than 0.001). No correlation was found among the changes in the considered parameters, suggesting that, at least in olive pollinosis, specific skin reactivity, specific IgE and specific IgG are three variables depending on IT but reciprocally independent.