ISSN:
1600-0536
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Introduction: Patients sensitized to para-phenylenediamine (PPD) have a high degree of patch test reactivity to Disperse Orange 3 (DO3), and a lesser one to Disperse Red 1 and Red 17. Two successive patients positive to PPD, Disperse Red 1 and 17, negative to DO3 were real eye-openers for our considerations about purity of our current allergen DO3.Materials and methods: We realized comparative thin-layer chromatography (TLC), with DO3 from Chemotechnique®(DO3-Chem) and Trolab®(both extracted from petrolatum), and “pure” DO3 from two chemical providers. TLC clearly indicated that DO3-Chem was not DO3. HPLC analysis with pure DO3 from Chemotechnique® and comparison of structures by NMR with samples of DO3, revealed that DO3-Chem was Disperse Orange 31 (DO31). In addition, signals through the GERDA network allowed the collection of test materials and observations. Among other members, only 2 used DO3-Chem (from 2 different batches) that was DO31 too, according to TLC Results: According to their data, they observed no or a lower reactivity to DO3 than expected (4 patients DO3-Chem + among 23 PPD+ e.g.). Finally, the error was proved to be due to the provider of the dye to Chemotechnique®, who likely deleted the 1 of Disperse Orange 31 on his packaging.Discussion: Chemical structure of DO31 indicates a possible in vivo hydrolysis into nitroaniline and a second compound, a substituted PPD derivative that clearly does not frequently react in PPD positive patients. Like drugs, patch tests are submitted to post-commercialization controls. In addition to allergens providers who should enhance their quality controls, dermato-allergologists have to be vigilant, and must active networks when they observe a rare bird.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.0105-1873.2004.0309m.x
Permalink