Persistently Vitreous Culture-Positive Exogenous Bacterial Endophthalmitis

Abstract

Purpose: To report the clinical settings, bacterial isolates, antibiotic sensitivities, and visual acuity outcomes of patients with persistently positive vitreous cultures after intravitreal antibiotics.

Design: Consecutive, noncomparative case series.

Methods: setting: Tertiary care center.

Patient population: Thirty-six eyes of 36 patients with exogenous endophthalmitis with the same bacterial organism identified on at least 2 consecutive vitreous cultures from 1981 to 2015.

Observation procedures: Vitreous cultures with intravitreal injections of antibiotics and pars plana vitrectomies with intravitreal antibiotics.

Main outcome measures: Bacterial isolates, antibiotic sensitivities, visual outcomes.

Results: Thirty-six eyes of 36 patients met the study criteria. The mean follow-up was 26.5 months. The most common clinical settings were after cataract extraction (18/36, 50%) and glaucoma surgery (11/36, 31%). The mean initial visual acuity was 2.16 ± 0.77 logMAR (Snellen equivalent ≈20/2900), and there was no statistically significant change at the final evaluation (2.08 ± 0.97 logMAR, ≈20/1900, P = .72). The most common bacteria were Staphylococcus (11/36, 31%) and Streptococcus (9/36, 25%). Gram-positive bacteria were sensitive to vancomycin (27/27, 100%); gram-negative bacteria were sensitive to amikacin (5/5, 100%). The antibiotic sensitivities were the same on repeat cultures in 34 of 36 patients (94%). The initial treatment was a vitreous culture and intravitreal injection of antibiotics in 28 of 36 patients (78%). The vision at the last follow-up was 20/200 or better in 12 patients (33%) and no light perception in 11 of 36 patients (31%).

Conclusions: The most commonly identified organisms were gram-positive bacteria. There was good concordance in the antibiotic sensitivities between initial and subsequent cultures. Patients with persistently vitreous culture-positive endophthalmitis had poor visual outcomes.