Factors Associated With Positive Microbial Culture in Patients With Endophthalmitis Based on Clinical Presentation and Multimodal Intraocular Sampling.

ABSTRACT

PURPOSE: The aim of this study was to identify the factors associated with positive culture sample in patients with endophthalmitis based on clinical presentation and multimodal intraocular sampling. DESIGN: Retrospective review. METHODS: A total of 259 subjects with a diagnosis of endophthalmitis presented to a tertiary ophthalmic referral center between 2006 and 2018. Patient demographics, presenting clinical findings and the results of aqueous and vitreous sampling were analyzed. RESULTS: Mean age was 64.2 (± 22.6) years with 52.9% female. Endophthalmitis followed cataract surgery in 84 eyes (32.4%) and was the most common precipitant; intravitreal injections were the next common cause involving 60 eyes (23.2%). Mean visual acuity on presentation was hand movements with a hypopyon present 134 eyes (52%). In total, 135 cases (52.1%) were culture positive. Aqueous sampling was performed in 112 eyes [culture positive 36 (32.1%)]; vitreous sample in 122 eyes [positive in 56 (45.3%)]. Vitrectomy was performed in 169 eyes with 149 sent for culture [70 (47.0%) positive]. A positive vitrectomy culture was observed in 14 eyes (36.9%) of 38, despite initial treatment with intravitreal antibiotics. Factors associated with positive culture were aqueous tap [odds ratio (OR) 2.06, P = 0.02], vitrectomy (OR 2.86, P = 0.001), and absent red reflex (OR 2.73, P = 0.001). CONCLUSIONS: A multimodal approach to intraocular sampling should be considered in those presenting with endophthalmitis, with both aqueous tap and vitrectomy associated with an increased probability of achieving a positive culture.