ASSESSMENT OF SKIN PRICK TEST AND SERUM SPECIFIC IGE DETECTION IN THEDIAGNOSIS OF CUPRESSACEAE-POLLINOSIS

Background: There is increasing evidence for the relevance of Cupressa ceae pollinosis among persons living in geographic areas where theses species are native or imported. Objective: Previously reported problem s in obtaining valid allergenic extracts to be used in the diagnosis o f this winter pollinosis prompted us to assess the value of available Cupressaceae pollen extracts for in vivo and in vitro diagnosis. Metho ds: Commercial and in-house allergenic extracts from Cupressaceae and Taxodiaceae families were used for skin prick testing and specific IgE detection in six groups of subjects exposed to a high concentration o f Cupressaceae pollen. Results: Four commercial and two in-house Cupre ssus sempervirens pollen extracts showed low cutaneous reactivity. Pos itive test results were recorded in 26% of the 713 subjects tested. C. arizonica in-house pollen extracts gave rise to larger cutaneous reac tions. Furthermore, the skin prick test response was positive in a gre ater number of subjects (38%) of the same group. Six commercial immuno assays were able to detect specific IgE to C. sempervirens in rates ra nging from 8.1% to 82.1%. Specific IgE to C. arizonica was detected by means of an inhouse immunoenzymatic method in 70.3% of 54 patients wi th suspected ''cypress'' allergy, and specific IgE to C. sempervirens was detected in 75.9% of these patients by using a commercial system. High rates of cross-reactivity within the Cupressaceae family and with species of the Taxodiaceae family were recorded with both in vivo and in vitro tests. Conclusions: The use of C. sempervirens in vivo diagn ostics should be carefully evaluated until better characterized extrac ts are developed. In-house-characterized extracts of C. arizonica seem to be more reliable in the diagnosis of Cupressaceae allergy by means of skin prick testing. The sensitivity of commercially available in v itro methods to detect specific IgE to C. sempervirens should be caref ully evaluated; nevertheless, valid results can be obtained with some already available immunoassays.