Abstract
Purpose :
To identify the microbiology and antibiotic resistance of contact lens (CL) and non-contact lens (NCL) related central corneal ulcers treated at the University of Chicago from 2009-2014 and compare the results with ulcers treated from 2002-2009.
Methods :
IRB approved chart review of patients treated for a corneal ulcer from 2009-2014. Patients were identified by ICD-9 diagnosis codes of corneal ulcer, corneal disorder due to contact lens, or corneal infiltrate. Isolated organisms and their antibiotic susceptibility were identified and analyzed relative to the prior cohort.
Results :
96 corneal ulcers were identified. 58 (60%) were central, sight threatening ulcers and were included in the study. 30 (52%) were CL and 28 (48%) were NCL associated ulcers. 56 (97%) were cultured with 45 (80%) positive results. Coagulase negative staphylococci (CoNS) was the most common organism overall, accounting for 37% of all central corneal ulcers. In NCL specifically, CoNS was the most common bacteria (41%) followed by methicillin-susceptible Staphylococcus aureus (15%) and alpha hemolytic streptococci (11%). In CL, Pseudomonas aeruginosa was the most common organism (41%) followed by CoNS (34%) and Klebsiella spp (10%). Resistance to ciprofloxacin was shown in 38% of CoNS and 17% of Pseudomonas isolates. Compared to the prior cohort, resistance to ciprofloxacin was demonstrated in 25% of CoNS and none in Pseudomonas. Gentamicin, tobramycin, and vancomycin show no change in antibiotic resistance.
Conclusions :
This 12-year analysis supports CoNS and Pseudomonas Aeruginosa as the most common bacteria in NCL and CL central corneal ulcers respectively. Likely due to widespread fluoroquinolone use, our latest cohort shows a trend of increasing resistance to fluoroquinolone antibiotic in two common organisms. The choice of antibiotic for bacterial keratitis should be made judiciously.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.