[Allergic contact eczema caused by henna tattoo]

Henna dye is obtained from the leaves of an indigenous tree, Lawsonia inermis. Contact dermatitis to henna is rarely reported. It is usually related to additives, especially oils or paraphenylenediamine. We report the case of a 9-year- old boy who developed an eczematous reaction at the site of application of a henna tattoo.

A henna tattoo was applied on the arm of a healthy 9-year-old boy on a Mediterranean beach. Four days later, the child noted pruritus followed multiple small papules and vesicles overlying the pattern of tattoo. He was treated with topical mometasone for 20 days, which produced gradual improvement and resolution.

Two months later, a patch test (True test) was performed on the upper back. The results were observed after 48 and 96 hours and showed positive reactions to p-phenylenediamine, PPD mix (black rubber mix) and paraben mix and was negative to natural henna.

Skin painting with henna is traditionally performed in Muslims or Hindus. The painting is usually performed on the hair, palms, soles of the feet and nails with henna that gives a red color. The addition of p-phenylenediamine to the henna mixture darkens the color. The mixtures used by the "artists" contained natural henna (a rare sensitizer) and chemical coloring agents: diaminotoluenes and diaminobenzenes such as paraphenylenediamine. Today, paint-on tattoos drawn on the skin by street or beach artists are very fashionable among Europeans in holiday resorts. Because of the worldwide fashion of skin painting, future cases of sensitization to p-phenylenediamine are expected.