para-Phenylenediamine (PPD) is a potent allergen with frequent exposure through use of hair dyes or henna tattoos.
We wished to determine if prevalence of PPD sensitivity is changing through time as trends in its use change.
A total of 3631 patients were patch tested consecutively with the environmental standard series between 2007 and 2014 to map the prevalence of PPD sensitivity and its distribution according to age, sex, and diagnosis.
Two hundred nine patients (5.75%) were proven to be PPD sensitive. Most PPD-sensitive patients were approximately in their 60s in 2007, whereas in 2014, they were in their 20s and 30s. In 2014, 61.1% of the patients were younger than 35 years and 50% were younger than 25 years. Of 209 PPD-sensitive patients, 32.5% had present relevance related to hair dyeing and eyebrow or eyelash coloring procedures. All affected male patients were hairdressers. Adverse reaction to henna was detected in only 1 case after henna hair dye use.
The 5.75% prevalence of PPD sensitization in our study was higher compared with that in the European data. It is alarming that PPD hypersensitivity occurred even among teenagers. This may be mainly explained by hair dyeing at an early age.