Does DNCB therapy potentiate epicutaneous sensitization to non-related contact allergens?

Abstract

Summary Nineteen patients suffering from alopecia areata were treated weekly with both 2,4‐dinitro‐chlorobenzene (DNCB) and dithranol applied to separate areas on the scalp. During treatment seven patients developed contact hypersensitivity to dithranol. Our findings indicate that repeated topical application of DNCB may increase the susceptibility of the treated individual to contact allergens. This would constitute a serious draw‐back in the acceptibility of DNCB immunotherapy.

Contact allergy to 3‐(4‘ methylbenzylidene) camphor and contact and photocontact allergy to 4‐isopropyl dibenzoylmethane

“…This phenomenon is different from crossreaction and corresponds to the promotion of contact allergy to a weak allergen by a strong allergen with different structure. Similarly, this mechanism has been observed between the strong allergen DNCB and dithranol as the weak allergen (5). In our case, the absence of allergic reaction to Parsol 1789 0.5% in oil paraffin and 2% in pet.…”

Nickel sensitivity as a complication of squaric acid dibutylester treatment of alopecia areata

“…(2) reported 2 patients with nickel dermatitis (but without any history of nickel sensitivity) while using DNCB for alopecia areata. De Groot et al (7) noted the appearance of sensitization to dithranol in 7 of 19 subjects treated by dithranol and DNCB. We report a new case of nickel contact dermatitis during immunotherapy for alopecia.…”