Microbiological spectrum and antibiotic sensitivity in endophthalmitis: a 25-year review.
OBJECTIVE
To identify the spectrum and susceptibility pattern of pathogens responsible for culture-positive endophthalmitis referred to a single institution and investigate possible trends in both pathogens and antibiotic sensitivities over the past 25 years.


METHODS
A retrospective, laboratory-based study of consecutive microbiological isolates.


METHODS
A total of 988 consecutive culture-positive endophthalmitis isolates from 911 eyes.


METHODS
All culture-positive endophthalmitis isolates collected from 1987 to 2011 were identified. Susceptibility rates to a variety of antibiotics were calculated. Chi-square test for trend was used to detect changes in spectrum or susceptibility over time.


METHODS
Microbial spectrum and susceptibility pattern over time.


RESULTS
A total of 988 isolates were identified from 911 eyes. The average patient age was 67 ± 18 years, and 55% of the patients were female. The most prevalent pathogens were coagulase-negative staphylococcus (39.4%), followed by Streptococcus viridans species (12.1%) and Staphylococcus aureus (11.1%). Gram-negative organisms and fungi accounted for 10.3% and 4.6% of all isolates, respectively. With the exception of 2 isolates, Enterococcus faecium and Nocardia exalbida, all the other 725 (99.7%) gram-positive bacteria tested were susceptible to vancomycin. Of the 94 gram-negative organisms tested against ceftazidime, 2 were of intermediate sensitivity and 6 were resistant. For 8 antibiotics, increasing microbial resistance over time was observed: cefazolin (P = 0.02), cefotetan (P = 0.006), cephalothin (P<0.0001), clindamycin (P = 0.04), erythromycin (P<0.0001), methicillin/oxacillin (P<0.0001), ampicillin (P = 0.01), and ceftriaxone (P = 0.006). For 3 antibiotics, increasing microbial susceptibility was observed: gentamicin (P<0.0001), tobramycin (P = 0.005), and imipenem (P<0.0001).


CONCLUSIONS
Coagulase-negative staphylococcus remains the most frequently identified cause of endophthalmitis. Vancomycin and ceftazidime seem to be excellent empiric antibiotics for treating endophthalmitis. Although a statistically significant trend toward increasing microbial resistance against a variety of antibiotics, including cephalosporins and methicillin, was observed, a significant trend toward decreasing microbial resistance against aminoglycosides and imipenem also was detected.
Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York; Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, New York; Department of Ophthalmology, Winthrop University Hospital, Mineola, New York. Electronic address: rgentile@nyee.edu.
Ronald C
RC
Gentile
Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York; Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, New York.
Salil
S
Shukla
Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York.
Mahendra
M
Shah
Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York; Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, New York.
David C
DC
Ritterband
Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York; Department of Ophthalmology, NYU School of Medicine and Vitreous Retina Macula Consultants of New York, P.C., New York, New York.
Michael
M
Engelbert
Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York; Department of Ophthalmology, San Antonio Uniformed Services Health Education Consortium, San Antonio, Texas.
Andrew
A
Davis
Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York.
Dan-Ning
DN
Hu
D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001431:Bacteriological Techniques; D024881:Drug Resistance, Bacterial; D009877:Endophthalmitis / Q000188:drug therapy / Q000382:microbiology; D015818:Eye Infections, Bacterial / Q000188:drug therapy / Q000382:microbiology*; D005260:Female; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D012189:Retrospective Studies
D000900:Anti-Bacterial Agents