Genotypic Resistance Analysis of Bacterial Species Involved in Infectious Keratitis

Area of Science:

• Ophthalmology
• Microbiology
• Genetics

Background:

• Infectious keratitis is a leading cause of corneal blindness globally.
• Antimicrobial resistance and rapid progression necessitate genotypic surveillance.

Purpose of the Study:

• To analyze bacterial pathogen distribution in infectious keratitis.
• To characterize genotypic resistance mechanisms, focusing on extended-spectrum β-lactamase (ESBL) genes.

Main Methods:

• Bacterial isolates from corneal scrapings underwent microbiological identification and antimicrobial susceptibility testing.
• Polymerase chain reaction (PCR) was used to detect resistance genes (tem, shv, ctx-M).
• Phenotypic resistance was assessed using the Vitek2 system.

Main Results:

• Gram-positive bacteria, particularly staphylococci, were predominant.
• Pseudomonas aeruginosa and Enterobacteriaceae were common Gram-negative pathogens.
• Tem genes were prevalent, often plasmid-mediated, correlating with phenotypic resistance.

Conclusions:

• A significant correlation exists between genotypic markers and resistance phenotypes in bacterial keratitis.
• Continuous molecular surveillance is vital for effective targeted therapy and improved patient outcomes.