Supplementary Material for: Evaluation of Methods for the Estimation of Threshold Concentrations by the Skin Prick Test
Dreborg S.
Holgersson M.
10.6084/m9.figshare.4542607.v1
https://karger.figshare.com/articles/dataset/Supplementary_Material_for_Evaluation_of_Methods_for_the_Estimation_of_Threshold_Concentrations_by_the_Skin_Prick_Test/4542607
<p><b><i>Background:</i></b> The allergen dose-response curve is flat;
thus, small changes in wheal size reflect large differences in skin
sensitivity. The sensitivity as measured by provocation tests is given
by the threshold concentration that causes symptoms and/or objective
signs. The threshold concentrations differ by several magnitudes between
the most and the least sensitive individuals clinically allergic to the
same allergen. Variation in technique can be minimized by relating
allergen responses to that to histamine. The aim here is to present and
validate simple methods for estimation of the skin sensitivity given as
the concentration inducing a wheal of the same size as that with the
positive reference, 10 mg/ml of histamine HCl, in the same patient. <b><i>Methods:</i></b>
Data from previously reported trials on the biological equilibration of
allergen extracts were used to document a method to calculate the
concentration of allergen required to induce a wheal of the same size as
that with 10 mg/ml of histamine dihydrochloride in the same patient,
and to validate the methods using the parallel line bioassay as the gold
standard. <b><i>Results:</i></b> The validated methods correlated well
with the results obtained using the gold standard method and provide
results of skin prick testing based on threshold concentrations of
allergen. <b><i>Conclusions:</i></b> The validated methods reduce the
error of differences in testing techniques and make it possible to
report skin sensitivity at threshold concentrations. A simple method to
be used in clinical practice and a method suitable to describe changes
in skin reactivity over time or during treatment are proposed.</p>
2017-01-12 10:35:27
Skin prick test
Allergen
Histamine
Dose response
Parallel line bioassay
Threshold concentration
Proficiency test