Fixed drug eruption caused by tosufloxacin tosilate

A 39-year-old woman presented with a purple-red macula, 2 cm in diameter, on the back of her right hand. She had had similar maculae at this location several times before and residual pigmentation had persisted for 6 months. Histopathological examination showed slight acanthosis of the epidermis and perivascular round-cell infiltration and melanophages in the dermis. Oral provocation tests with five drugs that the patient had received as common-cold treatments on different occasions were positive only in the case of tosufloxacin; after an hour the skin lesion reappeared. To our knowledge this is the first published report of a fixed drug eruption caused by tosufloxacin, although such eruptions have previously been reported for several other fluoroquinolones.