Elicitation response characteristics to mono- and to N,N′-diacetyl-para-phenylenediamine

• Published in: Contact dermatitis Vol. 58; no. 6; pp. 355 - 358
• Main Authors: Blömeke, Brunhilde, Pietzsch, Tim, Merk, Hans F.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.06.2008; Blackwell
• Subjects: Acetylation; allergic contact dermatitis; Allergic diseases; Biological and medical sciences; Coloring Agents - adverse effects; Coloring Agents - pharmacokinetics; Cross Reactions; Dermatitis, Allergic Contact - diagnosis; Dermatitis, Allergic Contact - etiology; Dermatitis, Allergic Contact - immunology; Dermatitis, Allergic Contact - metabolism; Eczema - etiology; Female; Humans; Immunopathology; Male; Medical sciences; metabolism; monoacetyl-PPD; N,N′‐diacetyl‐PPD; N-acetyltransferases; N′-diacetyl-PPD; para-phenylenediamine; patch test; Patch Tests; Phenylenediamines - adverse effects; Phenylenediamines - immunology; Phenylenediamines - pharmacokinetics; Skin - enzymology; Skin allergic diseases. Stinging insect allergies; T-cell stimulation; Immunopathology; Allergy; Skin disease; N,N'- diacetyl-PPD; allergic contact dermatitis; para-phenylenediamine; Stimulation; Metabolism; monoacetyl-PPD; Phenylenediamine; T-cell stimulation; Contact dermatitis; T-Lymphocyte; patch test; Elicitation; Patch; N-acetyltransferases; Skin test
• ISSN: 0105-1873; 1600-0536; 1600-0536
• DOI: 10.1111/j.1600-0536.2008.01347.x

Background:  Para‐phenylenediamine (PPD) is an important and common cause of allergic contact dermatitis. The mechanism of sensitization is still unknown. It is believed that PPD is a prohapten and thus the balance between activation and/or detoxification processes may influence responses to PPD. Beside auto‐oxidation to Bandrowski’s base, PPD is enzymatically acetylated to monoacetyl‐PPD (MAPPD) and to N,N′‐diacetyl‐PPD (DAPPD) in skin and keratinocytes. Objective:  We investigated if the 2 acetylated PPD derivatives are able to elicit allergic contact dermatitis by performing epicutaneous skin tests in subjects with dermatitis. Patients and Methods:  Contact allergy to PPD and the 2 acetylated derivatives (1% in petrolatum) were detected by patch testing of 455 patients with eczema from our clinic who were tested with the baseline series. Results and Conclusions:  16 subjects were found to be patch test positive to PPD (3.5%). No reactions were found for MAPPD, and just 1 PPD‐positive patient was positive for DAPPD (0.2%). In agreement with our earlier published in vitro data, these in vivo patch test results indicate that acetylation of PPD can be regarded as a detoxification reaction.