Fine-tuning the use of a skin prick test device

Abstract

BackgroundSkin prick tests (SPTs) are the gold standard for the diagnosis of IgE-mediated allergic diseases. Newly introduced devices have different results in performance. This study aimed to provide data for sensitivity, reproducibility, and acceptability of a new SPT device by using different techniques. MethodsThe study was conducted in 4 sections. Different application techniques were evaluated. In the first section, a drop of histamine/saline was put by vial (V). In the second section, it was taken from a well via the test device (W). ALK® Lancet served as a reference in both sections. The techniques were as follows; 1) apply vertical pressure (VP/WP), 2) apply vertical pressure and rotate 90° clockwise (VC/WC), 3) apply vertical pressure and rotate 90° clockwise and then counter-clockwise (VCC/WCC). Pain assessment was performed by using the Wong-Baker FACES Pain Rating Scale. Different histamine concentrations were transferred from the well by the Oryum device and applied as WC in section 3. Lancet and Oryum-WP were compared in terms of time and allergen adequacy in section 4. ResultsIn the first section the sensitivity of all techniques for Oryum and lancet were 100%. The false positivity of Oryum-VP, WP and lancet were found 0%. The Oryum-VP technique was found the best for intrapatient coefficient of variation (CV) (10.72%) (p < 0.001). The interpatient CV was similar in the Oryum-VP, VC, VCC and lancet techniques and was different from the Oryum-WP (p < 0.001). In the second section, all Oryum techniques yielded high sensitivities (100%). False-positive results were obtained more in Oryum-WC and WCC. Oryum-WP technique had the lowest pain score. In the 3rd section, the high positive correlation between histamine concentrations was observed (r = 0.731). In terms of time and allergen adequacy, Oryum-WP was superior to the lancet. ConclusionOryum-VP and WP techniques are reliable, tolerable and comparable with the lancet technique.