Notable endophthalmitis study fails to alter U.S. practice pattern

Eric D. Donnenfeld

The landmark European Society of Cataract and Refractive Surgeons study on the prophylaxis of endophthalmitis has yet to alter the way U.S. cataract surgeons approach the infection for a variety of reasons, according to two experts.

“I am surprised at how little this study has changed practice in the United States,” Eric D. Donnenfeld, MD, told Ocular Surgery News. “I have not seen a significant increase in the use of intracameral antibiotics. In fact, the antibiotic that was used in the ESCRS study was cefuroxime, and that’s almost never used here in the United States.”

The multicenter, multinational ESCRS study, published in 2006, looked at results of 13,698 patients who received injections of intracameral cefuroxime and/or perioperative levofloxacin eye drops. The study found that the incidence rate of endophthalmitis was nearly five times greater when intracameral cefuroxime was not used.

After the study was published, many in Europe adopted intracameral injections, altering the practice pattern there. In the U.S., however, response to the results was mixed. There are probably more physicians in the U.S. now using intracameral injections, but not to the extent that physicians are in Europe and parts of Asia, Francis S. Mah, MD, told OSN.

“I don’t think it’s a wholesale change in practice in the U.S., compared to what occurred in Europe, where people took this to be a paradigm shift and pretty much now, if you go to almost any European country, it’s accepted almost like a new standard of care,” Dr. Mah said.

Statistics illustrate the point: A 2007 survey of American Society of Cataract and Refractive Surgery members found that 77% of respondents did not plan to use intracameral injections. In contrast, a 2009 survey of United Kingdom antibiotic prophylaxis practice found that 55% of respondents were using intracameral cefuroxime, while the balance said that they would switch if a “commercially pre-formulated preparation” became available.

Reasons for limited U.S. impact

Respondents to the ASCRS survey cited multiple reasons as to why they were not injecting antibiotics, with 89% citing more study of intracameral injections needed before they adopted the practice; 45% citing concern about risk; and 11% citing cost as prohibitive.

Those results still hold 2 years later. Safety is one of the major factors holding back U.S. physicians from adopting intracameral injections, Dr. Mah said. Although 18% of ASCRS study respondents use pharmacies to prepare intracameral antibiotics, 77% have their nursing staff prepare the drugs. This practice can result in mistakes, Dr. Mah said.

“From my perspective, we need to answer these practical issues of how to get the antibiotic from a sterile package into the eye in a reproducible manner, so that there are no dilutional errors or breaks in the sterility,” Dr. Mah said.

American methods of prevention against endophthalmitis differ in other ways from those used in Europe. In the U.S., fourth-generation fluoroquinolones are regularly used topically, whereas intracameral cefuroxime is rarely used.

In addition, rates of endophthalmitis cited in the ESCRS study appeared higher than in the U.S. It was only in the intracameral cefuroxime group that there was a comparable rate of endophthalmitis to the U.S., prompting some to suggest that the current practice pattern in the U.S. should continue unaltered because the infection rate is already low, Dr. Mah said.

Possible future of study impact

The use of intracameral injections by a majority of cataract surgeons in the U.S. could be possible. The ASCRS study found that 82% of respondents would use intracameral antibiotic injections if a “reasonably priced commercial preparation” was on the market.

The ESCRS endophthalmitis study results make sense, Dr. Mah said. It demonstrates what has been hypothesized about more antibiotics inside the eye reducing the possibility of infection.

“I do think that if there was safe, effective, maybe even [U.S. Food and Drug Administration]-approved mechanism for injecting antibiotics into the eye … there would be a radical shift in what the U.S. surgeons were doing,” he said.

Dr. Donnenfeld said the ESCRS endophthalmitis study has presented the idea of injected intracameral antibiotics to American physicians, along with evidence that prophylaxis of endophthalmitis can be effective.

“This study has opened up the concept that intracameral antibiotics are a reasonable thing to do,” Dr. Donnenfeld said. “I don’t think it’s changed surgical practice, but it has changed the mindsets of ophthalmologists.” – by Erin L. Boyle

References:

• Chang DF, Braga-Mele R, Mamalis N, et al, for the ASCRS Cataract Clinical Committee. Prophylaxis of postoperative endophthalmitis after cataract surgery: results of the 2007 ASCRS member survey. J Cataract Refract Surg. 2007;33(10):1801-1805.
• Gore DM, Angunawela RI, Little BC. United Kingdom survey of antibiotic prophylaxis practice after publication of the ESCRS Endophthalmitis Study. J Cataract Refract Surg. 2009;35(4):770-773.

• Eric D. Donnenfeld, MD, can be reached at OCLI, 2000 North Village Ave., Rockville Centre, NY 11570; 516-766-2519; fax: 516-766-3714; e-mail: eddoph@aol.com.
• Francis S. Mah, MD, can be reached at University of Pittsburgh Medical Center, Eye and Ear Institute, 203 Lothrop St., Eighth Floor, Pittsburgh, PA 15213; 412-647-2200; fax: 412-647-5119; e-mail: mahfs@upmc.edu.