Microbial keratitis in los angeles: the doheny eye institute and the los angeles county hospital experience.

Objective: To evaluate the spectrum and antibiotic susceptibility panel of infectious keratitis at a major tertiary care referral eye center and a major county hospital in Southern California.

Design: Retrospective case series.

Participants: All cultured infectious keratitis cases from July 1, 2008, through December 31, 2012, from the Doheny Eye Institute (DEI) and the Los Angeles County + University of Southern California Medical Center (LAC+USC) were evaluated.

Methods: Microbiology records were reviewed retrospectively.

Main Outcome Measures: Microbial isolates as well as antibiotic susceptibility patterns were analyzed.

Results: One hundred eighty-four (63%) of 290 cases showed positive culture results at DEI and 152 (82%) of 186 cases showed positive culture results at LAC+USC. Gram-positive pathogens were found to be the most common at both DEI (70%) and LAC+USC (68%), with coagulase-negative Staphylococcus being the most common gram-positive organism (58% at DEI and 44% at LAC+USC). Pseudomonas aeruginosa was the most common gram-negative organism (57% at DEI and 43% at LAC+USC). Ciprofloxacin and levofloxacin susceptibility for all tested pathogens was 73% at DEI and 81% at LAC+USC (P = 0.16). Oxacillin-resistant Staphylococcus aureus (ORSA) was found in 42% of cases at DEI and in 45% of cases at LAC+USC (P = 1.00).

Conclusions: There is no significant difference in the spectrum of pathogens or antibiotic susceptibility of pathogens at DEI versus LAC+USC, and ORSA was found in approximately half of all S. aureus samples.