Pain perception and performance of three devices for single-site allergen skin testing

Abstract

Skin testing remains the preferred method for most allergists for establishing the presence of allergen sensitization. This study examined the performance of a new single-site skin test device that incorporates initial pressure to reduce the sensation of pain. Comparators were a conventional skin testing system and a smallpox needle. Twenty subjects were tested on the back, four sites with histamine and four sites with saline with each of the three skin testing devices. The single-site skin test device was applied with downward pressure, the conventional skin testing system, and smallpox needle (SPN) by pricking at a 45°angle. Outcomes were size and reproducibility of the skin test reactions and discomfort, as graded by the subject. The whealing responses to histamine were larger with the conventional skin testing system than with the single-site skin test device and both produced larger wheals than the SPN. The conventional skin testing system also produced greater intrasubject variability. Only the conventional skin testing system produced wheals of >3 mm with saline. There was no significant difference in perception of pain, which was low with all three devices. All three devices were well tolerated, without a significant difference in perception of discomfort. Testing with histamine revealed differences in wheal size and reproducibility among the three devices and testing with saline revealed differing likelihood of inducing a significantly sized wheal.