title: Dapsone-induced photodermatitis in a patient with linear IgA dermatosis.
abstract: Dapsone (4, 4' diaminodiphenylsulfone) is an efficient antiinflammatory agent. Its therapeutic use may result in a variety of adverse effects. The most frequent unwanted reactions are hemolytic anemia and methemoglobinemia. By oral route dapsone is mainly metabolized to monoacetyldapsone (MADDS) and hydroxylamine dapsone (DDS-NOH). We report a 76-year-old female patient with linear IgA dermatosis who developed a dapsone-induced photosensitivity 8 weeks after initiation of sulfone therapy. She showed a widespread erythematous eruption in UV-exposed skin area. After clearing of skin lesions the photopatch test revealed positive reactions to dapsone, MADDS and DDS-NOH. Dapsone-induced photosensitivity to date has been described only in leprosy patients. We demonstrate for the first time that this adverse reaction is not restricted to leprosy and that dapsone metabolites may also contribute to the mechanism of photosensitivity like the parent sulfone. Dapsone-induced photosensitivity is a rare, not dose-related adverse effect of the sulfone and can also occur in patients with inflammatory skin disorders.
authors.affiliation: Department of Dermatology, University Hospital Carl Gustav Carus, Technical University of Dresden, Fetscherstr. 74, 01307 Dresden, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Stöckel
authors.forename: M
authors.initials: M
authors.lastname: Meurer
authors.forename: G
authors.initials: G
authors.lastname: Wozel
mesh_terms: D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects*; D003622:Dapsone / Q000009:adverse effects*; D005148:Facial Dermatoses / Q000139:chemically induced* / Q000473:pathology; D005260:Female; D006801:Humans; D007070:Immunoglobulin A; D010328:Patch Tests; D010787:Photosensitivity Disorders / Q000139:chemically induced* / Q000473:pathology; D012872:Skin Diseases, Vesiculobullous / Q000188:drug therapy*; D013909:Thorax
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007070:Immunoglobulin A; D003622:Dapsone