title: Systemic quinine photosensitivity with photoepicutaneous cross-reactivity to quinidine.
abstract: A 75-year-old man developed an eczematous eruption on the face and dorsal aspects of the hands one July after 3 weeks' treatment with quinine, 0.25 g nightly, for nocturnal leg cramps. The photoreaction cleared within a week of quinine being stopped. UVA and UVB erythema threshold determinations, after the acute episode had subsided, were normal. A photopatch test was positive for irradiated quinine down to a concentration of 0.01% and for unirradiated quinine to 0.5%. The test with the isomer quinidine was positive only when irradiated, down to a concentration of 0.01%. Preirradiated samples of quinine and quinidine were negative. Whereas in contact allergy quinine and quinidine usually do not cross-react, after systemic photosensitization, the 2 isomers probably form a common photoproduct, accounting for the cross-reactivity.
authors.affiliation: Department of Dermatology, Lund University, General Hospital, Malmö, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Ljunggren
authors.forename: M
authors.initials: M
authors.lastname: Hindsén
authors.forename: M
authors.initials: M
authors.lastname: Isaksson
mesh_terms: D000368:Aged; D006801:Humans; D008297:Male; D010328:Patch Tests; D010787:Photosensitivity Disorders / Q000139:chemically induced* / Q000175:diagnosis; D011802:Quinidine / Q000737:chemistry; D011803:Quinine / Q000009:adverse effects* / Q000737:chemistry; D014466:Ultraviolet Rays
chemical_list: D011803:Quinine; D011802:Quinidine