JAMA Ophthalmology has published 10-year results of the ongoing, multicenter, prospective Antibiotic Resistance Monitoring in Ocular micRoorganisms (ARMOR) surveillance study evaluating profiles and trends in antibiotic resistance among common ocular bacterial pathogens across the United States. ARMOR is the only ongoing surveillance study of its kind. The study was sponsored by Bausch & Lomb.
The analysis of the 10-year results, which evaluated data from bacterial isolates collected from 2009 to 2018, showed that in vitro antibiotic resistance is prevalent in the US among ocular staphylococci. One in three Staphylococcus aureus and one in two coagulase-negative staphylococci (CoNS) were methicillin-resistant, and three in four methicillin-resistant staphylococci were multidrug-resistant (to ≥three classes of antibiotics).
“Antibiotic resistance, which can complicate the choice of antibiotic in clinical practice and, in some cases lead to treatment failure, is a growing concern that can make it difficult for eye care professionals to effectively treat their patients with eye infections,” said Penny A. Asbell, M.D., lead ARMOR study author, professor and chair, the University of Tennessee Health Science Center, and director, Hamilton Eye Institute, Memphis, Tenn. “Many eye care professionals treat their patients empirically, so the data collected in this unique ARMOR study are vital in that they can help guide eye care professionals in selecting the most appropriate treatment option to meet the needs of their patients.”
In total, ARMOR study participants from 88 sites across 41 US states collected a total of 6,091 isolates of S. aureus, CoNS, Streptococcus pneumoniae, Pseudomonas aeruginosa and Haemophilus influenzae, all organisms frequently implicated in bacterial infections of the eye. Overall, 34.9 percent of S. aureus and 49.3 percent of CoNS were methicillin-resistant and more likely to be concurrently resistant to other antibiotic classes. As well, multidrug resistance was high among methicillin-resistant S. aureus (75.4 percent) and CoNS (73.7 percent). In vitro resistance among S. pneumoniae was highest for azithromycin (36.3 percent); while P. aeruginosa and H. influenzae demonstrated low resistance overall. Differences in antibiotic resistance were found among isolates by patient age in staphylococci, by geographic region (all but H. influenzae), and over time.
“The ARMOR study is critically important research for the eye health community as it is the only ongoing source of information about the changing in vitro resistance patterns of significant ocular pathogens across the United States, providing a platform to identify key trends and provide insights to eye care professionals,” said Yolande Barnard, vice president and general manager, U.S. Pharmaceuticals, Bausch + Lomb. “We are committed to continuing our support of ARMOR long-term as part of our ongoing commitment to meet the evolving needs of eyecare professionals and their patients.”