Endophthalmitis caused by Enterococcus faecalis: clinical features, antibiotic sensitivities, and outcomes

Abstract

Purpose: To report the clinical features, antibiotic sensitivities, and visual acuity outcomes of endophthalmitis caused by Enterococcus faecalis.

Study design: Retrospective, observational case series.

Methods: A consecutive case series of patients with culture-positive endophthalmitis caused by E. faecalis between January 1, 2002, and December 31, 2012, at an academic referral center.

Results: Of 14 patients identified, clinical settings included bleb association (n = 8), occurrence after cataract surgery (n = 4), and occurrence after penetrating keratoplasty (n = 2). All isolates were vancomycin sensitive. When comparing isolates in the current study with isolates from 1990 through 2001, the minimal inhibitory concentration required to inhibit 90% of isolates increased for ciprofloxacin (4 μg/mL from 1 μg/mL), erythromycin (256 μg/mL from 4 μg/mL), and penicillin (8 μg/mL from 4 μg/mL), indicating higher levels of resistance. The minimal inhibitory concentration required to inhibit 90% of isolates remained the same for vancomycin (2 μg/mL) and linezolid (2 μg/mL). Presenting visual acuity ranged from hand movements to no light perception. Initial treatment strategies were vitreous tap and intravitreal antibiotic injection (n = 12) and pars plana vitrectomy with intravitreal antibiotic injection (n = 2). Visual acuity outcomes were 20/400 or worse in 13 (93%) of 14 patients.

Conclusions: Although all isolates were sensitive to vancomycin and linezolid, higher minimal inhibitory concentration required to inhibit 90% of isolates in the current study, compared with isolates from 1990 through 2001, occurred with ciprofloxacin, erythromycin, and penicillin. Despite prompt treatment, most patients had poor outcomes.