Abstract
Purpose :
Local, national and or international antimicrobial surveillance programs can provide information on emerging resistance and/or nonsusceptibility rates among ocular isolates. Nonsusceptibility rates are impacted by geography, dispensing patterns, patient population and evaluation period. Our purpose was to test the hypothesis that local/regional nonsusceptibility trends are required for antibiotic selection and management of ocular infection.
Methods :
We compared regional nonsusceptibility trends for coagulase negative staphylococci (CoNS) recovered from endophthalmitis cases with national and international ocular surveillance data for methicillin, moxifloxacin, and aminoglycosides. Data for CoNS isolates from a United States (US-FL) regional tertiary/academic medical center collected for three time periods, 2009-2013 (intraocular fluids (IOFs), n=97), 2011-2015 (IOFs, n= 105), 2011-2015 (all ocular sources, n=362) were compared to nonsusceptibility rates reported by the national, multicenter five-year Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) Surveillance Study 2009-2013 (all ocular, n=992) and the recent European Surveillance Study documenting activity of fluoroquinolones and aminoglycosides against ophthalmic pathogens (2010-2011, n=313).
Results :
Methicillin nonsusceptibility rates ranged from 49.7% (ARMOR) to 55.3% (Europe). Resistance rates for the (US-FL) isolates were 53.6%, 50.5% and 53.7% respectively. No significant differences were noted. Methicillin nonsusceptible isolates were significantly (p <0.0001) more likely to be resistant to moxifloxacin and gentamicin for all sites and time periods. Overall, fluoroquinolone nonsusceptibility rates were highest for isolates from the two US study periods (IOFs-56.1%, 50.1%, all-39%) and lowest (32%) for ocular isolates from Europe. Reported nonsusceptibility rates for the ARMOR study was 32.2%. Gentamicin nonsusceptibility rates were significantly higher for isolates from Europe (28.4%, 89/313) vs IOFs, 11.6%, 5.1% or general isolates (12%, 43/362) from US. Rates for tobramycin were significantly (p =0.002) higher for ARMOR (32%, 319/992) isolates, than for isolates from Europe (23%, 73/313).
Conclusions :
Emerging nonsusceptibility trends for fluoroquinolones and the aminoglycosides are geography, patient population and source specific.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.