Haruki Katahira, Shigeto Kumakura, Takaaki Hattori, Hiroshi Goto

To report the adverse event of topical tosufloxacin administered after penetrating keratoplasty in one patient. A 60-year-old female was referred to our hospital for treatment of vision loss due to corneal opacification, etiology was unknown. Slit lamp examination showed dense opacification in corneal stroma. Penetrating keratoplasty was performed on her left eye. She was treated with topical applications of 1.5% levofloxacin, 0.5% cefmenoxime, 0.1% betamethasone, 0.1% hyaluronate sodium, and 3% aciclovir after penetrating keratoplasty. Delayed epithelialization of the donor graft was observed at day 4 post-transplantation. Because of the concern that levofloxacin induced corneal epithelialization delay, 1.5% levofloxacin was changed to 0.3% tosufloxacin. At day 6 post-transplantation, deposits on the epithelial defect of the donor graft were observed. Tosufloxacin was suspected to be the cause of deposits, and tosufloxacin eye drop was discontinued. The deposits decreased gradually and completely disappeared by 5 months post-transplantation. Topical tosufloxacin treatment has the risk of precipitation on compromised corneas such as corneal grafts with epithelial defect after penetrating keratoplasty. After discontinuation of therapy, the deposit may resolve spontaneously without surgical removal.