Listeria monocytogenes and ocular abscess: an atypical but yet potential association.

PURPOSE: To report a farmer's corneal abscess caused by an unusual pathogen: Listeria monocytogenes fluoroquinolone resistant.

METHODS

A 78-year-old farmer presented a central corneal abscess associated with 1-mm hypopyon and decreased visual acuity evolving since 2 weeks. First an antibiotic therapy associating oral ofloxacin and topical ciprofloxacin, vancomycin and ceftazidime was started. Different samples of the abscess were performed and sent to different microbiological laboratories.

RESULT: Listeria monocytogenes was isolated after 2 days of culture. Antibiotics sensitivity showed resistance to ciprofloxacin, fosfomycin and fusidic acid. Ceftazidime was changed for gentamicin, and after 1 month of treatment the abscess decreased considerably.

CONCLUSION

This case demonstrated that even if Listeria is rarely involved in ocular abscess, it must be evocated for people with risk factors as farmers. This suspicion should lead to an extended incubation to identify the pathogen. The analysis of Listeria resistance is essential to start an efficient therapy.