Reducing post-cataract surgery endophthalmitis: Investigators focus on therapeutic regimen

This article was reviewed by Yusen Huang, MD

Adding cefuroxime to the irrigating solution used during cataract surgery appears to be a safe and effective method for reducing the risk of postoperative endophthalmitis, according to researchers who reported their experience with this technique in a recently published retrospective study.¹

The investigation included 61,299 eyes. Of the total cohort, 15,948 eyes were operated on between January 1, 2012, and December 31, 2014, using plain balanced salt solution (BSS) as the irrigating solution (control group), and 45,351 eyes underwent cataract surgery between January 1, 2015, and December 31, 2019, using irrigating solution that contained cefuroxime 1500 µg/mL.

The mixture was prepared by withdrawing 10 mL BSS from the irrigating solution and injecting it into a vial of cefuroxime 750 mg. The reconstituted solution was injected back into the BSS container.

The rate of endophthalmitis was significantly decreased after the transition to intraoperative irrigation with cefuroxime. Endophthalmitis occurred in 11 eyes (0.07%) in the group that did not receive intraoperative cefuroxime and in 5 eyes (0.01%) when cefuroxime was used in the irrigating solution (P < .01).

Cultures were positive for bacteria in 4 of the 11 cases in the control group and in 1 of the 5 eyes in the intraoperative cefuroxime group (P > .05). No safety issues were associated with intraoperative cefuroxime irrigation.

Discussing the research, Yusen Huang, MD, PhD, of the Shandong Eye Institute, Shandong First Medical University and Shandong Academy of Medical Sciences in Qingdao, People’s Republic of China, pointed out that although intracameral antibiotics are already widely accepted as a method for endophthalmitis prophylaxis in patients undergoing cataract surgery, the optimal choice of prophylactic routes and antibiotics is controversial.

“In European countries, commercial cefuroxime formulation (Aprokam) has been widely used, and the dose administered is the same as in the European Society of Cataract and Refractive Surgeons (ESCRS) randomized prospective study demonstrating its efficacy,” Huang said.

Surgeons have been reluctant to adopt intracameral cefuroxime because it is off-label and carries potential risks.

The study

“In our study, the manner of cefuroxime preparation was modified so that it involved only a 1-step process. This makes it simpler, saves resources, and could reduce the potential risks of both preparation errors and contamination,” Huang pointed out. “Although the intracameral concentration achieved with our approach is estimated to be 1500 µg/mL, or only about 45% of the ESCRS recommendation, we found that it reduced the rate of postcataract surgery endophthalmitis by about sevenfold.”

Furthermore, Huang explained that “during the last 2 years in our hospital where more than 25,000 cases of cataract surgery have been performed using intraoperative cefuroxime irrigation, not a single patient developed endophthalmitis.

It should be noted, however, that this method is not recommended for use in patients with a history of vitrectomy, [considering] the potential for rapid posterior segment diffusion of the antibiotic and potential macular toxicity.”

Although adding cefuroxime to the irrigating solution is still an off-label use of the medication, the authors suggested that it represents a good option for countries with no licensed product for intracameral use of endophthalmitis prophylaxis and particularly in developing regions where the risks for both endophthalmitis and a poor outcome may be higher given a variety of contributory factors.

Throughout the entire study period, all patients received the same preoperative antisepsis with application of topical povidone-iodine.

In addition, all patients started using topical levofloxacin 0.5% solution preoperatively and continued it postoperatively, along with a topical steroid and topical nonsteroidal anti-inflammatory drug.

Follow-up visits

Postoperative follow-up visits were scheduled at 1 and 4 days, 4 weeks, and 12 weeks, but patients were instructed to seek care if they developed pain, redness, or loss of vision.

The analyzed outcome was onset of acute-onset endophthalmitis, which was diagnosed if a patient presented within 6 weeks of surgery with eye pain, anterior chamber reaction or flare, hypopyon, and/or vitritis with causes for intraocular inflammation other than endophthalmitis excluded.

The 16 cases of endophthalmitis recorded during the 9-year study period developed at a median of 7.56 days after cataract surgery (range, 1-21 days).

None of the cases occurred in a patient who had an intraoperative complication or was noted to have incision leakage at the time endophthalmitis was identified.

Isolates from the culture-positive cases of endophthalmitis in the control group included Staphylococcus hominis subsp, Neisseria mucosa, Corynebacterium xerosis, and Enterococcus faecalis.

Streptococcus gordonii was identified as the causative pathogen in the culture-positive case of endophthalmitis among patients who received intraoperative cefuroxime, and the organism was found susceptible to cefuroxime.

Reference
1. Ma X, Zie L, Huang Y. Intraoperative irrigation prophylaxis for acute-onset endophthalmitis after phacoemulsification surgery. Infect Drug Resist. 2020;13:1455-1463