A Case of Mixed Enterobacter Infection in a Patient with Canaliculitis Caused by a Punctal Plug

Purpose: To report a case of mixed <i>Enterobacter</i> infection associated with canaliculitis caused by a permanent punctal plug.Case summary: A 73-year-old woman presented to our hospital with bilateral purulent discharge and conjunctival injection. She had a history of permanent punctal plugs inserted into the lower lacrimal puncta of both eyes five months earlier for the treatment of dry eye syndrome. Slit-lamp examination revealed purulent discharge from the lower puncta of both eyes, along with edema and tenderness around the plugs. Based on these findings, canaliculitis was diagnosed in both eyes. The plugs were removed, a culture test was performed, and empirical antibiotic treatment was initiated. <i>Enterobacter cloacae</i> and <i>Enterobacter asburiae</i> were identified by the right punctal plugs. According to antibiotic susceptibility testing, inflammation improved following instillation of 0.5% levofloxacin hydrate (Cravit<sup>®</sup>; Santen Pharmaceutical Co., Ltd., Osaka, Japan) eye drops every 4 hours.Conclusions: A case of canaliculitis with mixed <i>E. asburiae</i> and <i>E. cloacae</i> caused by a permanent punctal plug was successfully treated by removing the plugs and administering sensitive antibiotics.