Hay Fever
Conditions
Brief summary
Skin prick tests (SPT) are commonly used in daily allergological practice to assess skin reactivity to allergens. Multiple factors can contribute to non-optimal results of conventional wheal and flare measurement (CWFM) of SPT such as inaccurate measurements, observer-dependency and absence of traceability. This study aims to evaluate the quantification of SPT by a novel High Speed Laser Doppler Imaging (HSL-DI) and to compare it with CWFM. First, SPT with birch and/or grass pollen extracts as well as positive and negative controls will be performed in 20 volunteers (11 atopics, 9 non-atopics) to establish the characteristics (cut-off, optimal reading time and allergen concentration) of HSL-DI analysis based on two parameters (area and flow measurement). In a second step, fifty patients will be tested with birch and grass pollen extracts at optimal allergen concentration and time window. Analysis of SPT by HSL-DI and CWFM will be compared.
Interventions
PROCEDUREAllergy test reading
Reading of allergy skin tests (in response to allergen extracts or histamine or negative control) by HSL-DI versus direct observer evaluation (CWFM)
Sponsors
Centre Hospitalier Universitaire Vaudois
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* age 18 to 65 years * history of allergic rhinitis to birch pollen and/or grass pollen.
Exclusion criteria
* any medical condition (including pregnancy) that could influence the study (viral or bacterial airway infection, active allergic rhinitis) * uncontrolled asthma (peak expiratory flow \<80% of volunteer's best personal value) * treatment with antihistamine medication less than two weeks before enrolment or during the trial.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Skin microcirculation flow changes over time (composite autcome) | tests reading at 2.5 min., 5 min., 7.5 min., 10 min., 12.5 min., 15 min., 17.5 min. and 20 min. | Skin microcirculation flow changes will be evaluated at 2.5 min., 5 min., 7.5 min., 10 min., 12.5 min., 15 min., 17.5 min. and 20 min. as measured in a composite outcome 1) by HS-LDI based on parameter area corresponding to the total number of non-zero pixels in the flare area and parameter flow as measured according to a specific formula in arbitrary units, or 2) as measured by conventional wheal and flare measurement (CWFM, direct observer reading) in mm. |
Countries
Switzerland
Outcome results
None listed