title: Spectrum of cross-photosensitization in 18 consecutive patients with contact photoallergy to ketoprofen: associated photoallergies to non-benzophenone-containing molecules.
abstract: Contact photoallergy to ketoprofen gels has been widely reported, and cross-sensitivity reactions with other compounds, such as tiaprofenic acid, fenofibrate and benzophenones, are well known. However, positive photopatch tests to other different non-benzophenone-related compounds have recently been observed. We report the results of photopatch testing in patients with contact photoallergy to ketoprofen and discuss the spectrum of cross-sensitization to ketoprofen. 18 consecutive patients with a history of photocontact dermatitis from ketoprofen were investigated. Patch and photopatch tests were performed. As expected, we observed positive photopatch tests to Ketum* gel and ketoprofen 2.5% in petrolatum in all patients (100%). However, it was remarkable to note positive photopatch tests to other unexpected and non-relevant allergens, including fentichlor (67%), tetrachlorosalicylanilide (28%), triclosan (17%), tribromsalan (11%) and bithionol (11%), with no clinical relevance. Interestingly, these agents belong to the family of halogenated salicylanilides and related compounds, which have been forbidden in Europe since the 1970s. Our results raise the question of hyper-photosusceptibility to non-relevant allergens induced by photosensitivity to ketoprofen. The mechanism may involve the high photoreactivity induced by the association of a benzene ring with an oxygen group.
authors.affiliation: Department of Dermatology, University Hospital, 2 Place Saint-Jacques, 25030 Besançon cedex, France.
authors.forename: E
authors.initials: E
authors.lastname: Durbize
authors.forename: M
authors.initials: M
authors.lastname: Vigan
authors.forename: E
authors.initials: E
authors.lastname: Puzenat
authors.forename: P
authors.initials: P
authors.lastname: Girardin
authors.forename: B
authors.initials: B
authors.lastname: Adessi
authors.forename: P H
authors.initials: PH
authors.lastname: Desprez
authors.forename: P H
authors.initials: PH
authors.lastname: Humbert
authors.forename: R
authors.initials: R
authors.lastname: Laurent
authors.forename: F
authors.initials: F
authors.lastname: Aubin
mesh_terms: D000328:Adult; D000485:Allergens / Q000009:adverse effects* / Q000737:chemistry; D001735:Bithionol / Q000009:adverse effects; D002733:Chlorophenols / Q000009:adverse effects; D003429:Cross Reactions; D017454:Dermatitis, Photoallergic / Q000209:etiology* / Q000473:pathology; D005260:Female; D006801:Humans; D007660:Ketoprofen / Q000009:adverse effects* / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D010328:Patch Tests; D012458:Salicylanilides / Q000009:adverse effects; D013329:Structure-Activity Relationship; D014260:Triclosan / Q000009:adverse effects
chemical_list: D000485:Allergens; D002733:Chlorophenols; D012458:Salicylanilides; D014260:Triclosan; C004361:tribromsalan; D007660:Ketoprofen; C007713:fentichlor; D001735:Bithionol