Late reactions to patch test preparations with reduced concentrations of p-phenylenediamine: a multicentre investigation of the German Contact Dermatitis Research Group

Abstract

The occurrence of late reactions to PPD may be influenced by patch test concentration and duration. PPD 0.4-0.5% pet. may cause late reactions indicative of active sensitization.

Factors associated with p‐phenylenediamine sensitization: data from the Information Network of Departments of Dermatology, 2008–2013

“…to, for example, 0.3% pet. leads to a significant loss of positive reactions, by 25%, and this loss is even more pronounced for weak positive reactions . Thus, bearing in mind that hair dyeing mostly leads to a weak degree of PPD sensitization, it is likely that the frequency of PPD sensitization by hair dyeing may have been underestimated in the EDEN study.…”

Contact allergy to ingredients of hair cosmetics – a comparison of female hairdressers and clients based on IVDK 2007–2012 data

“…After p ‐phenylenediamine (PPD) at 1% in petrolatum had been removed from the German baseline series in 2005, because of concerns regarding the risk of active sensitization, and although a suitable lower concentration had not yet been identified , PPD had been included in the hairdresser series in January 2010, still at 1% pet. The prevalence of sensitization both in hairdressers and in clients were very similar to that observed with toluene‐2,5‐diamine (PTD).…”

New positive patch test reactions on day 7—The additional value of the day 7 patch test reading

“…In general, contact allergies may be associated with several patient characteristics. These include sex, age, and occupational dermatitis . Women tend to have a higher prevalence of contact allergies than men .…”

“…These include sex, age, and occupational dermatitis. [22][23][24][25][26][27][28][29][30] Women tend to have a higher prevalence of contact allergies than men. 26 Thus, the effect of age can be only partly moderated by the exposure to allergens.…”