Department of Dermatology, University Hospital Erlangen, Erlangen, Germany.
Department of Dermatology, Clinical Centre Darmstadt, Darmstadt, Germany.
J Eur Acad Dermatol Venereol. 2018 Nov;32(11):1972-1976. doi: 10.1111/jdv.14999. Epub 2018 Jun 13.
Intradermal test is used to detect causative allergens in IgE-mediated hypersensitivity. The surfactant polysorbate 80 can be added to intradermal test solutions to more reliably dissolve the allergen and ensure a constant bioavailability of the injected allergen. Polysorbate 80 has, however, some histamine-releasing properties which could blur the difference to the histamine-induced wheal. Routinely serving as a control.
Allergen-free polysorbate 80 containing (0.005%) test solutions were therefore systematically tested at different injection volumes to see whether polysorbate can falsify skin reactions and if yes whether conditions can be identified to avoid this.
In a partly blinded study, 30 patients were tested intracutaneously at the back: each received at three separate sites 0.05 mL of polysorbate-containing solvent, 0.02 mL polysorbate-containing solvent as well as 0.02 mL polysorbate-free solvent. After 15 min, wheal and erythema were documented and planimetrically quantified.
Unexpectedly 23 of 30 (77%) patients showed false-positive test reactions to the volume of 0.05 mL of the polysorbate-containing solvent whereas the polysorbate-containing solvent with 0.02 mL and the polysorbate-free solvent with 0.02 mL injection volume had no reinforcing effect on skin test reaction.
Different volumes of polysorbate-containing solutions, all recommended by manufacturers for intradermal tests, may significantly influence test results. The study shows that a polysorbate 80 used at 0.005% in solvents for intradermal test to provide a better bioavailability of allergens produces false-positive reactivity in a surprising and a hitherto unknown 77% if the 0.05 mL volume is injected. It is, therefore, mandatory to strictly adhere to an intradermal test volume of 0.02 mL as only then falsifying effects of the polysorbate additive are avoided, and comparable test results are ensured.
皮内试验用于检测 IgE 介导的过敏反应中的致敏原。表面活性剂聚山梨酯 80 可添加到皮内试验溶液中，以更可靠地溶解过敏原，并确保注射过敏原的恒定生物利用度。然而，聚山梨酯 80 具有一些释放组胺的特性，这可能会使组胺诱导的风团与皮内试验结果难以区分。聚山梨酯 80 通常作为对照物。
因此，系统地测试了不同注射体积的不含过敏原的聚山梨酯 80（0.005%）试验溶液，以确定聚山梨酯是否会伪造皮肤反应，如果可以的话，是否可以确定避免这种情况的条件。
在一项部分盲法研究中，30 名患者背部进行皮内试验：每位患者在三个不同部位分别接受 0.05 mL 含聚山梨酯的溶剂、0.02 mL 含聚山梨酯的溶剂以及 0.02 mL 不含聚山梨酯的溶剂。15 分钟后，记录风团和红斑，并进行平面量化。
出乎意料的是，30 名患者中的 23 名（77%）对 0.05 mL 含聚山梨酯溶剂的体积出现假阳性试验反应，而 0.02 mL 含聚山梨酯溶剂和 0.02 mL 不含聚山梨酯溶剂对皮肤试验反应没有增强作用。
不同体积的含聚山梨酯溶液，均按制造商推荐用于皮内试验，可能会显著影响试验结果。该研究表明，如果注射 0.05 mL 体积，在皮内试验中使用浓度为 0.005%的聚山梨酯 80 以提高过敏原的生物利用度，会产生令人惊讶的、迄今为止未知的 77%的假阳性反应。因此，必须严格遵守皮内试验 0.02 mL 的体积，以避免聚山梨酯添加剂的伪造作用，并确保可比较的试验结果。
