Clinical Features, Antibiotic Susceptibilities, and Treatment Outcomes of Endophthalmitis Caused by Staphylococcus epidermidis

Abstract

To report the clinical features, antibiotic susceptibilities, and visual acuity outcomes with endophthalmitis caused by methicillin-sensitive Staphylococcus epidermidis and methicillin-resistant S.epidermidis. Retrospective case series. All patients seeking treatment at a tertiary referral center between 2006 and 2016 with endophthalmitis caused by S.epidermidis. All records were reviewed for patients with a clinical diagnosis of endophthalmitis and positive vitreous culture results for S.epidermidis. Data were compared with the prior series at the same institution. Clinical settings, antibiotic susceptibilities, and visual acuity. Among 96 eyes of 96 patients, the most common postprocedural clinical settings were cataract surgery (47/96 [49%]), intravitreal injection (21/96 [22%]), trauma (8/96 [8%]), glaucoma surgery (7/96 [7%]), and penetrating keratoplasty (5/96 [5%]). The initial treatment included intravitreal vancomycin and ceftazidime in 89 of 96 eyes (93%) and intravitreal vancomycin and amikacin in 7 of 96 eyes (7%). A vitreous tap and injection with antibiotics was performed as the initial treatment in 83 of 96 eyes (86%) and pars plana vitrectomy was performed in 13 of 96 eyes (14%). All isolates were sensitive to vancomycin in both decades. In the most recent series, visual acuity at last follow-up was 5/200 or better in 68 of 96 eyes (71%) compared with 71 of 86 eyes (83%) in the prior study. In the current study, susceptibility to methicillin and moxifloxacin was present in 45 of 96 eyes (47%) and 29 of 85 eyes (34%), respectively, compared with 34 of 86 eyes (40%) and 27 of 39 eyes (69%) in the prior study. Final visual acuity was not significantly different between those eyes that were methicillin or fluoroquinolone sensitive and those that were resistant. In the current and prior series, all S.epidermidis isolates were sensitive to vancomycin. Visual acuity outcomes were not dependent on methicillin or fluoroquinolone sensitivity.