March 2026 in “Indian Dermatology Online Journal” This report details a case study where a 40-year-old woman experienced allergic contact dermatitis and angioedema-like symptoms after using PPD-containing hair dye. Patch testing confirmed a positive reaction to PPD, highlighting the substance's potential to cause both T-cell and IgE-mediated hypersensitivity reactions.
February 2026 in “PubMed” This study reported that para-phenylenediamine and toluene-2,5-diamine are the main sensitizers in hair dye-related allergic contact dermatitis, with significant cross-reactivity to several other compounds.
15 citations
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June 2015 in “F1000Research” This study examined immune responses to Diphencyprone and found that its induced skin reactions have higher levels of negative immune regulators compared to psoriasis, suggesting differences in immune regulation may contribute to psoriasis chronicity.
15 citations
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July 2002 in “Australasian Journal of Dermatology” In this case report, two plywood mill workers developed allergic contact dermatitis due to exposure to uncured phenol-formaldehyde resin, not sawdust as initially suspected.
12 citations
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June 2010 in “Journal of dermatology” This study found that hyperpigmentation following contact immunotherapy for severe alopecia areata may indicate poor treatment responsiveness and aligns with characteristics of pigmented contact dermatitis.
