[Etiological analysis on bacterial endophthalmitis].
OBJECTIVE
To investigate the spectrum of organisms causing bacterial endophthalmitis and their sensitivities to commonly used ocular antibiotics.


METHODS
A retrospective analysis on microbiological records of 728 intraocular specimens of patients with suspected endophthalmitis from January 1999 to December 2006. Antibiotic susceptibility of these isolates was determined for commonly used ocular antibiotics using the Kirby-Bauer disk-diffusion test.


RESULTS
In all, 168 organisms were isolated from 728 intraocular specimens during the study interval. Overall, 96 (57.1%) of 168 isolates were Gram-positive cocci, 52 (31.0%) were Gram-negative bacilli, 18 (10.7%) were Gram-positive bacilli, and 2 (1.2%) were Gram-negative cocci. The most common organisms identified were Staphylococcus epidermidis in 21.4% (36/168), Staphylococcus aureus in 11.3% (19/168), and Pseudomonas aeruginosa in 8.9% (15/168). For Gram-positive cocci, sensitivities were the following: vancomycin 93.4% (85/91), levofloxacin 84.4% (81/96), ofloxacin 68.8% (66/96), ciprofloxacin 59.4% (57/96), gentamicin 56.3% (54/96), and tobramycin 43.8% (42/96). For Gram-negative bacilli, sensitivities were the following: levofloxacin 88.2% (45/51), ofloxacin 76.9% (40/52), ciprofloxacin 75.0% (39/52), gentamicin 49.0% (25/51), and tobramycin 48.1% (25/52). Comparing the data from 2003 to 2006 with the data from 1999 to 2002, the susceptibility of organisms to frequently employed antibiotics was decreasing.


CONCLUSIONS
The spectrum of organisms causing bacterial endophthalmitis is complex, and no single antibiotic provided coverage for all of the microbes isolated from intraocular specimens with bacterial endophthalmitis. Combination therapy is recommended as the initial empiric treatment of suspected bacterial endophthalmitis.
Ren
Zhe
Z
Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Capital University of Medical Sciences, Beijing 100005, China.
Wang
Zhi-qun
ZQ
Li
Ran
R
Luo
Shi-yun
SY
Deng
Shi-jing
SJ
Sun
Xu-guang
XG
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D002648:Child; D002675:Child, Preschool; D009877:Endophthalmitis / Q000382:microbiology*; D015818:Eye Infections, Bacterial / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult