Kentにおける微生物性角膜炎の10年間の微生物学的プロファイルとin vitro抗菌感受性分析：Kent微生物性角膜炎研究

To evaluate the incidence, microbiological profile, and in vitro antimicrobial susceptibility patterns of microbial keratitis (MK) in Kent over a 10-year period.

A retrospective analysis was conducted of all corneal scrape specimens processed between January 2015 and August 2024 at Maidstone and Tunbridge Wells NHS Trust and East Kent Hospitals University NHS Foundation Trust. Data extracted included patient demographics, isolates, and antimicrobial sensitivities. The study period was divided into two time periods (2015-2019 and 2020-2024) for trend analyses.

The estimated mean incidence of MK was 2.2 per 100,000 population per year. Of 1029 scrapes, 384 were culture-positive (37.3%). Gram-negative organisms predominated (50.9%), followed by Gram-positive (37.8%), fungi (5.0%), and Acanthamoeba (6.3%). Polymicrobial infections accounted for 10.4% of cases. Pseudomonas spp (35.9%), Coagulase-negative Staphylococci (15.0%), and Staphylococcus aureus (9.8%) were most commonly isolated. Average susceptibility of Gram-positive organisms to chloramphenicol, fluoroquinolones, and gentamicin was 96.7%, 76.0% and 92.1%, respectively, and for Gram-negative organisms was 48.2%, 93.4%, and 99.3%, respectively. Concerning trends included a 16.9% reduction in fluoroquinolone susceptibility among Gram-positive isolates (p < 0.001), with moxifloxacin efficacy decreasing by 57.9% (p = 0.002). The prevalence of Acanthamoeba represents an unrecognised regional disease burden, exceeding other UK regions (1.1-4.8%).

This study identified a marked decline in fluoroquinolone susceptibility among Gram-positive organisms and a significantly higher acanthamoeba prevalence compared to other UK regions and global reports. These findings highlight the importance of ongoing antimicrobial stewardship and support re-evaluation of empiric treatment protocols for MK in Kent.