Endogenous Endophthalmitis: yield of the diagnostic evaluation

Abstract

Background: Endogenous endophthalmitis is an infection of the eye secondary to sepsis, occurring in 0.04-0.5% of bacteremia or fungemia. Risk factors include intravenous drug abuse (IVDA), diabetes, indwelling catheters, and immune suppression. Many patients have known or suspected bacteremia or fungemia; however, culture yield is reported to be low (approximately 50%). The purpose of this study is to elucidate the yield of diagnostic evaluation including microbial cultures over a 6.5 year period at an academic center in the United States. Methods: Retrospective chart review of patients with endogenous endophthalmitis at the University of Florida from June 2011 to February 2018. Results: Included are 40 eyes of 35 patients. Endophthalmitis was secondary to an endogenous source in 23.5% of all endophthalmitis cases observed. Intraocular culture positivity was 28.6% overall but was 0% after initiation of systemic antibiotics. Most commonly identified organisms from the eye were coagulase-negative Staphylococcus and Candida. Blood culture positivity was 48.6%, most commonly Staphylococcus. IVDA was noted with increasing frequency as a risk factor. Diagnosis of endophthalmitis upon hospital admission was associated with a higher intraocular culture positivity (P = 0.040) and a shorter hospital stay (P = 0.035). Computed tomography (CT) and magnetic resonance imaging (MRI) were the highest yield imaging modalities; X-ray and non-ocular ultrasound were less diagnostically useful. Echocardiogram was positive by transesophageal route (TEE) in 22% and in 9% by transthoracic (TTE) testing. Following discharge from the hospital, 48.4% of patients failed to follow up with outpatient ophthalmology. Conclusions: Based on the results of this study, the interdisciplinary team should consider directed imaging, eye cultures prior to antimicrobial administration, thorough history for IVDA, and caution with premature discharge from the hospital.

Endogenous Endophthalmitis: A Review of Case Series Published between 2011 and 2020

“…In the case series published in the past 3 years in Western countries, IVDA was an important risk factor, present in 8.3% to 43.3% of patients [ 12 – 14 ]. In a review of 343 EE cases reported between 1986 and 2012, Jackson et al found an association with IVDA in 5% of cases [ 5 ].…”

“…Blood cultures have a low yield in EFE (9.2% to 25.6%) and a very high yield in EKE (66.6% to 92.9%). To maximize the rate of positive results, the blood sampling should be performed during fever spikes, before systemic treatment (and three consecutive blood samples should be taken) [ 14 , 18 ].…”

“…Malignancies were also reported in 11.7% to 33% of patients. In studies published in Western countries between 2017 and 2020, IVDA was the leading risk factor, presented in 8.3% to 43.3% of patients [ 12 – 14 ]. There was also a paper reporting 30 patients in which all cases were drug abuse-related [ 15 ].…”

“…The rate of positive vitreous cultures ranged from 18% to 100%. Regan et al found 28.6% positive results, but when patients with prior antibiotic treatment were excluded, the percentage grew to 41.7% [ 14 ]. Ratra et al reported that ocular fluid samples gave more positive results than blood cultures, probably because all patients with suspected EE immediately underwent an aqueous tap in the outpatient department [ 7 ].…”

“…Initial systemic therapy is empirical, and the recommendations differ significantly: oral ciprofloxacin (750 mg twice a day) [ 8 ], systemic vancomycin [ 14 ], or intravenous cefotaxime (1 g thrice a day), and intravenous gentamycin (80 mg twice a day) [ 7 ]. After receiving the microbiology test results, the treatment is tailored accordingly.…”