MedicalResearch.com Interview with
Ronald C Gentile, MD, FACS, FASRS
Professor of Ophthalmology
Chief, Ocular Trauma Service (Posterior Segment)
The New York Eye and Ear Infirmary of Mount Sinai
New York, NY 10003
Medical Research: What are the main findings of the study?
Dr. Gentile: We had three main findings in our study on the microbiological spectrum and antibiotic sensitivity in endophthalmitis over the past twenty- five years at the New York Eye and Ear Infirmary of Mount Sinai.
First Finding: The first main finding of the study was that there has not been any major change in the types of organisms causing endophthalmitis over the past 25 years. The most common cause of endophthalmitis in the study was bacteria, 95%, with most, 85%, being Gram-positive bacteria. The most prevalent organisms isolated were coagulase-negative staphylococcus, making up about 40% of the cases. This was followed by Streptococcus viridans species in about 12% and Staphylococcus aureus in about 11%. Gram-negative organisms accounted for about 10% and fungi for about 5%.
Second Finding: The second main finding of the study was that the current empiric intravitreal antibiotics used for treating endophthalmitis, vancomycin and ceftazidime, continue to be an excellent choice. The overwhelming majority of microorganisms causing endophthalmitis are susceptible to this combination. Over 99% of the Gram-positive isolates were susceptible to the vancomycin and about 92 percent of the Gram-negative isolates were susceptible to ceftazidime.
Third Finding: The third main finding of the study was that there was increasing microbial resistance to eight antibiotics including cefazolin, cefotetan, cephalothin, clindamycin, erythromycin, methicillin/oxacillin, ampicillin, ceftriaxone and decreasing microbial resistance to three antibiotics including gentamicin, tobramycin, and imipenem. For example, Staph Aureus isolates resistant to methicillin increased from 18% in the late 1980s to just over 50% this past decade while gentamicin-resistance endophthalmitis isolates decreased during the same time period from 42% to 6%.