Microbial profile in infectious keratitis over 8 years in Sao Paulo, Brazil: pathogens and microbial resistance
Abstract Objective Infectious keratitis remains a sight-threatening disease and its prompt diagnosis and treatment are critical. This study investigated the microbiological patterns of isolates in corneal ulcers in a tertiary health center in an 8-year period. Methods Retrospective analysis of scrapes of microbial keratitis performed from January 2013 to December 2020. Demographics and microbiological data were collected. Results A total of 446 scrapes were performed on eyes of 433 patients, 270 male (62.4%), mean age 51.7 years. 304 organisms were isolated from 248 (55.6%) positive samples. Polymicrobial infections occurred in 47 samples (19.0%). Bacterial isolates represented 86.8%: 53.3% gram-positive (GP), 33.5% gram-negative (GN). Cutibacterium acnes (12.2%) and Pseudomonas aeruginosa (9.9%) were the most common bacteria. Fungal keratitis comprised 11.8% of the isolates; Fusarium sp (6.2%) was the main fungus isolated. GP tested were sensitive to vancomycin, 98.7% of the GN were sensitive to ceftazidime. All Pseudomonas aeruginosa were sensitive to gentamicin and ciprofloxacin. Conclusion Gram-positive bacteria were predominant in keratitis isolates. In severe bacterial keratitis in our area, vancomycin should be considered as empirical treatment.