Focus Session

Introduction: Disperse dyes (DDs) are utilised for colouring synthetic textile fibres, including polyester, polyamide, acetate, and acrylic, and are recognised as contact sensitizers. The textile dye mix (TDM) 6.6% in petrolatum currently tested in baseline series contains Disperse Blue (DB) 35, Disperse Yellow 3, Disperse Orange (DO) 1 and 3, Disperse Red 1 and 17, and DB 106 and 124. Prevalence of contact allergy to TDM is approximately 2%–4%. The most frequent allergen in TDM-positive patients is DO 3. Around 85% of para-phenylenediamine (PPD)-allergic dermatitis patients have been positive to DO 3 in several studies. There has been a discussion to exclude DO 3 from TDM 6.6% with the aim to avoid these frequent, strong, and concurrent positive reactions to TDM and PPD.<br/><br/>Objectives: To determine whether a revised TDM without DO 3, in conjunction with PPD, could identify as many or more patients allergic to textile dyes compared to TDM 6.6%.<br/><br/>Methods: This research encompassed a collaboration of 11 dermatology clinics globally, from the 1st of January 2020 to the 31st of December 2020.<br/><br/>Patch tests were performed on 2951 dermatitis patients with TDM 6.6%, TDM 7.0% (without DO 3 but with the other disperse dyes at 1.0% each), DO 3 1.0%, and PPD 1.0% pet.<br/><br/>Results: Contact allergy to TDM 6.6% was 4.3% and to TDM 7.0% 3.5%. 63/69 DO 3-positive patients were positive to PPD. The 102 patients positive to TDM 7.0% plus the 28 positive to PPD and TDM 6.6% but negative to TDM 7.0% were 130, outnumbering the 127 positive to TDM 6.6%.<br/><br/>Conclusion: TDM 7.0% combined with PPD testing identified more positive reactions than TDM 6.6%, suggesting the exclusion of TDM 6.6% from the ICDRG baseline series in favour of TDM 7.0%.