Both prompt globe closure and treatment with subconjunctival antibiotics may reduce the risk of endophthalmitis development in patients with open globe injuries, according to a study published in Clinical Ophthalmology.
Researchers conducted a retrospective review of all surgically managed cases of open globe injury treated at the University of Michigan between January 2000 and July 2017 to evaluate both risk and protective factors for endophthalmitis development in this patient population.
A total of 993 cases of open globe injuries were diagnosed during the study period, with 586 cases eligible for inclusion in the review. Of these, 75.4% were in men (mean age, 40.7±25.1). Mean follow-up time was 1079.8±1895.7 days and median follow-up time was 443 days.
A majority of the eyes presenting with open globe injury had no previous history of ocular surgery. Within the cohort, data on time from injury to presentation was available for 99.5% of cases; 13.2% of patients presented more than 24 hours after their initial injury.
Researchers found that, within this patient cohort, open globe injuries typically resulted in “profound vision loss.” The mean presenting logMAR visual acuity was 2.1±1.0, while mean logMAR visual acuity was 1.3±1.2 at the time of the last documented follow-up — a statistically significant improvement vs presentation.
An intraocular foreign body (IOFB) was noted in 14.8% of patients, 30 and 48 of which were located in the anterior and posterior chambers, respectively. Of the IOFBs removed after primary globe closure, median time to removal was 2 days after injury.
Investigators noted that 4.3% of eyes had suspected endophthalmitis. Delayed presentation was seen in 40% of these cases, and 24% involved an IOFB. Of the 52% of cases that developed endophthalmitis after globe closure, median time to diagnosis was 5 days after presentation. Fifty-six percent of patients with endophthalmitis had a zone 1 injury only.
Initial management consisted of tap and intravitreal antibiotic injection in 72% of patients; 16% required pars plana vitrectomy with intravitreal antibiotic injection, and 12% required primary enucleation. Only 48% of patients were culture-positive, with organisms including Bacillus cereus, coagulase negative Staphylococcus, Candida albicans, Clostridium bifermentans, Enterococcus faecalis, Group A Streptococcus, Haemophiles influenzae, and Streptococcus pneumoniae. Two enucleated eyes had Gram-positive rods on pathology.
Among the 12 culture-positive cases, 5 had available sensitivity and resistance data. Only 1 coagulase-negative Staphylococcus isolate demonstrated intermediate fluoroquinolone sensitivity.
The most frequently used antibiotic combination was vancomycin and ceftazidime (72% of cases). Final visual acuity was generally poor, with a mean logMAR visual acuity of 1.9±1.3. Five eyes required enucleation.
Investigators performed a multivariable logistic regression analysis to determine statistically significant risk and protective factors; intravitreal antibiotics were not included in these analyses, despite the suggestion of a statistically significant risk in the univariate analysis.
Results indicated that time to globe repair (odds ratio [OR], 4.5), zone I injury (OR, 3.6), and the need for additional surgery (OR, 5.5) were risk factors for endophthalmitis development. Subconjunctival antibiotics (OR, 0.3) were associated with a decreased endophthalmitis risk, and were used in 74.9% of cases.
Overall, 315 eyes received subconjunctival cephalosporin, 93 received subconjunctival vancomycin, 64 received subconjunctival ceftazidime, and 14 received subconjunctival aminoglycoside. A majority of patients — 69.5% — received IV antibiotics, including penicillin-based antibiotics (213 eyes), fluoroquinolones (93 eyes), and a penicillin-based antibiotic combined with a fluoroquinolone (32 cases). In over 90% of cases, IV antibiotics were administered as one-time doses.
The use of these IV antibiotics for any duration — including 1-time dosing, more than 1 dose but less than 24 hours, and more than 24 hours of IV antibiotics — were not statistically significant protective factors against endophthalmitis.
Intravitreal antibiotics were used in 12.9% of cases and topical antibiotics were used postoperatively in 94.5% of cases. Oral antibiotics were used in 34.3% of cases for a mean duration of 7.6±3.0 days, and similarly, their use was not protective against endophthalmitis development.
The presence of an intraocular foreign body was not a statistically significant risk factor for endophthalmitis development.
Study limitations include potentially higher rates of endophthalmitis due to the center being a tertiary referral center.
“We believe that a standardized protocol that utilizes a one-time dose of IV fluoroquinolone antibiotics, globe closure within 24 hours whenever possible, and prophylactic intravitreal antibiotics in cases involving delayed IOFB removal provides effective prophylaxis against endophthalmitis in [open globe injuries].”
Durrani AF, Zhao PY, Zhou Y, et al. Risk factors for endophthalmitis following open globe injuries: A 17-year analysis. Clin Ophthalmol. 2021;15:2077-2087. doi:10.2147/OPTH.S307718