Allergy to Cynodon dactylon (Cyn d) pollen in seasonal rhinitis, comparison between skin tests and component-resolved diagnosis (CRD) in Bahía Blanca (Argentina).
Sunday, March 4, 2018
South Hall A2 (Convention Center)
German D. Ramon, MD FAAAAI, Valentina Viego, Nadia Arango, Maria A. Long, Adrian Kahn, MD FAAAAI, Laura B. Barrionuevo
RATIONALE: Studies using CRD in patients with seasonal allergic rhinitis have not been reported in Argentina. In addition, there are few studies that describe the skin sensitivity to different grass pollens in these group of patients. Our goal is to compare the sensitivity of both techniques to the Cynodon dactylonallergen.

METHODS: A retrospective observational study of 37 patients diagnosed with seasonal allergic rhinitis was performed. Patients were studied using skin tests with extracts of Cynodon dactylon pollen from Alergo Pharma SRL, Argentina (GREER® Skin Testing Devices GreerPick™), along with blood tests using the CRD test (ImmunoCAP Isac; Thermo Fisher Scientific Inc., UK). Comparisons were done with X2 test and correlations done with Spearman and Kendall tests. P<.05 was considered significant. Statistical analysis of the results was performed using STATA Statistical program.

RESULTS: The prevalence of cutaneous sensitivity was 48.6% (95% CI = 31.9-65.6) and in vitro test, 81.1% (95% CI = 64.8-92.0). There was positive correlation between both methods using Kendall (0.13) and Spearman (0.33) correlation tests. Comparison between both techniques showed = 4.4703 (Pr = 0.034).

CONCLUSIONS: Skin test to Cynodon dactylon showed less reactivity than in vitro specific IgE measurement with immunocap test, with 65% reactivity in skin test and 90% reactivity in the in vitro test. Both tests proved to be useful for the diagnosis of allergy to Cynodon dactylon in patients with allergic rhinitis in Bahia Blanca.