Validation of the latex glove provocation procedure in latex-allergic subjects

Background: A latex provocation test is needed to clarify the allergic status of patients who present with a positive clinical history for latex allergy and a negative latex skin test and/or serologic test. Objective: In the present study, we aimed to optimize and validate the performance and safety of a latex glove provocation protocol and to employ it to verify the barrier properties of the Dermapor expanded polytetrafluorethylene (ePTFE) glove liner (liner) for latex glove allergen. Methods: Twenty-one skin test positive latex-allergic subjects donned goggles and a silicone mask, washed their hands and then put high allergen-containing latex gloves (mean = 15,072 AU/mL) on a moist, bare and liner-covered hand, Due to an absence of verifiable reactions on the bare hand in the first five subjects, the protocol was modified to puncture the skin in three sites on the hand prior to donning the liner/glove or latex glove alone. Subjects were observed for 30 minutes for localized allergic symptoms (pruritus and hives). Lined and unlined hands were compared for reactions. Results: Application of highly allergenic latex gloves onto the bare hands of five skin test-positive, latex-allergic subjects produced some mild pruritus but no visually detectable dermatitis, In contrast, all 17 latex-allergic subjects who underwent the modified glove challenge protocol involving a puncture prior to glove application experienced intense pruritus with measurable wheals and erythema at sites where their skin was punctured. Equivalent wheal and erythema reactions were observed at a site where a puncture was performed directly through the glove. These same subjects experienced no pruritus or hives on their opposite hands that received a liner prior to latex glove application, Conclusions: Direct application of highly allergenic latex gloves onto the hands of skin test-positive, latex-allergic individuals does not commonly produce localized allergic symptoms after minutes, especially if the subject has successfully avoided latex and has no evidence of dermatitis. By puncturing the skin prior to latex glove donning, quantifiable hives are produced within 15 minutes allowing glove application. A Dermapor ePTFE liner prevents the transfer of allergen from gloves onto the skin and therefore can serve to minimize contact exposure as part of avoidance therapy.