Abstract
Purpose :
Endophthalmitis can be a blinding condition and a vitreous sample helps to guide antibiotic treatment. Samples are routinely obtained prior to vitrectomy at the bedside, but less commonly utilized after antibiotic treatment, at the time of pars plana vitrectomy (PPV). Our goal was to analyze the utility of gram stain and culture data from vitrectomy samples in patients already treated with bedside tap and inject.
Methods :
A retrospective chart review from August 2016 until November 2017 of patients diagnosed with endophthalmitis that underwent bedside vitreous tap and inject followed by a subsequent PPV. All bedside tap and injects and PPVs were performed by the retina service at The New York Eye and Ear Infirmary of Mount Sinai (NYEE). Surgical pathology and microbiology samples from before and after vitrectomy were reviewed.
Results :
A total of 30 eyes in 30 patients received a bedside tap and inject and 17 (56.7%) underwent subsequent PPV at NYEE. All bedside tap and injects were performed on same day of presentation, and subsequent PPV was performed 1 to 32 days after presentation. 4 of the initial 17 (23.5%) vitreous taps were unsuccessful and aqueous was sent. 5 of the initial 16 (31.3%) gram stains were positive for organisms compared to 7 of the 13 (53.8%) gram stains after vitrectomy. 8 of 17 (47.1%) of pre vitrectomy cultures (plates or PCR) were culture positive and 2 of 12 (16.7%) post treatment vitrectomy cultures were culture positive. 6 of 13 (46.2%) were positive on gram stain after treatment while corresponding cultures were negative. Of these 6, 2 (33.3%) were found to have persistent anterior chamber cell one month after PPV.
Conclusions :
Gram stains and cultures from vitrectomy, after initial antibiotic treatment, provide useful clinical information. Gram stains can reveal persistent cells even when cultures show no growth. Persistent inflammation in the eye may partially be attributed to persistent bacterial antigen in the eye as evidenced by gram stain. A more sensitive technique for analyzing vitreous samples is needed to better characterize bacterial antigens found on gram stain. Further studies are needed to show that a positive yield on gram stain with negative vitreous culture may relate to worse patient outcomes.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.