May 2008
Volume 49, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2008
Reduced Glycopetide and Mupirocin Susceptibility Among Ocular Staphylococci
Author Affiliations & Notes
  • D. Miller
    Bascom Palmer Eye Institute, University of Miami Miller School of Med, Miami, Florida
  • E. Alfonso
    Bascom Palmer Eye Institute, University of Miami Miller School of Med, Miami, Florida
  • M. Diaz
    Bascom Palmer Eye Institute, University of Miami Miller School of Med, Miami, Florida
  • E. Perez
    Bascom Palmer Eye Institute, University of Miami Miller School of Med, Miami, Florida
  • Footnotes
    Commercial Relationships  D. Miller, None; E. Alfonso, None; M. Diaz, None; E. Perez, None.
  • Footnotes
    Support  NEI Core Grrant P30 EY014801, Research to Prevent Blindness
Investigative Ophthalmology & Visual Science May 2008, Vol.49, 1989. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      D. Miller, E. Alfonso, M. Diaz, E. Perez; Reduced Glycopetide and Mupirocin Susceptibility Among Ocular Staphylococci. Invest. Ophthalmol. Vis. Sci. 2008;49(13):1989.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: : Gram positive isolates are the most common pathogens recovered from ocular infectious diseases. Glycopeptides remain antibiotics of last resort for the treatment of these infections. The focus of this study was to report reduced in vitro susceptibility to glycopeptide antibiotics among ocular staphylococci from keratitis and endophthalmitis and to evaluate the in vitro susceptibility of mupirocin to inhibit or kill these isolates.

Methods: : Vancomycin susceptibility MIC distribution data for Staphylococcus aureus, Coagulase Negative Staphylococci (CoNS), were collected and compared for time periods 1990-1994, 1995-1999, 2000-2004, and 2005-11-30, 2007. MICs were determined using the Vitek Auto Microbial System and E tests. MIC concentrations ranged from 0.25 ug-32 ug/ml (vitek) and 0.016-256 ug/ml for the E tests. Susceptible MICs were ≤2 ug/ml for S. aureus and ≤4 ug/ml for Coagulase Negative Staphylococci. Staphylococci isolates were also screened for hetero ( 1-4 ug/ml), intermediate (8-16 ug/ml) and high level glycopeptide resistance (≥ 32) using the E test macromethod (EMAC) (N=96) and glycopeptide resistance detection strips (EGRD, n=94). E tests were used to detected mupirocin resistance ( ≥ 512,n=91).

Results: : Modal MIC (MIC50)-≤1 ug/ml and MIC90 (2 ug/ml) for S. aureus remain stable from baseline (1990-1994, N=634) to the current period (N=515). At baseline 98% of isolates were susceptible to a vancomycin concentration of ≤1 ug/ml, but declined to 62% for the current period. At baseline 94% of CoNS isolates (N=125) were inhibited by <1 ug/ml, but only 20% were susceptible during 2005-November 2007 (N=67). Low level resistance was detected in 80% of the staphylococci isolates with both screening methods. Hetero-resistance ranged from 2.1% (EMAC) to 4.2% (EGRD) and were highest for CoNS (43.7) and MRSA (5.3%). High level mupirocin resistance was detected in 27.5% of the staphylococcal isolates, 41.9%-CoNS, 32.1%-MRSA and 9.4%-MSSA.

Conclusions: : . Reduced glycopeptide susceptibility was confirmed in at least 80% of evaluated staphylococcal isolates. The impact of these results on clinical outcomes needs investigation.

Keywords: antibiotics/antifungals/antiparasitics • bacterial disease • Staphylococcus 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×