title: Idiopathic photodermatitis with a positive paraphenylenediamine photopatch test.
abstract: A 61-year-old man was seen for a long-standing, recurrent eczematous dermatitis that appeared only in the summer. A patch test with ammoniated mercury was positive. Photopatch reactions to caine mix and paraphenylenediamine were positive, and phototesting disclosed an idiopathic photosensitivity to UV-A. Avoidance of sunlight exposure and the use of chemical sunscreening agents prevented further recurrence of the dermatitis.
mesh_terms: D000779:Anesthetics, Local / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D010328:Patch Tests; D010655:Phenylenediamines / Q000009:adverse effects; D010787:Photosensitivity Disorders / Q000139:chemically induced* / Q000175:diagnosis; D014466:Ultraviolet Rays / Q000009:adverse effects
chemical_list: D000779:Anesthetics, Local; D010655:Phenylenediamines; C029728:4-phenylenediamine