Abstract
Purpose :
Corneal melting and infection remain a common complication in keratoprosthesis (K-pro). Previous studies have shown the presence of bacterial biofilms on the ocular surface. Biofilms provide bacterial populations with protection from antimicrobials and can generate low-grade local inflammation. This study is undertaken to analyze the Biofilm formation on the K-Pro surface and bandage contact lens as a potential source of inflammatory mediators and infectious microorganisms increasing the risk of sight-threatening infections.
Methods :
Patients with keratoprosthesis and contact lenses were prospectively followed. Contact lenses of the patients were collected and sent for microbiology analysis. The presence of biofilm and microorganisms was documented. Antibiotic susceptibility, minimum biofilm inhibitory concentration (MBIC) and minimum biofilm eradication concentration (MBEC) were obtained. The effect of 1% povidone on antibiotic penetration was documented. Using laboratory-grown bacteria with biofilm-forming capacity, the effectivity of different antibiotics and povidone were studied.
Results :
20 contact lenses of 20 eyes were collected. The mean time of use of contact lens is 6 months (1 - 14 months). The most common prophylactic antibiotic regimen used by these patients was vancomycin followed by Polymyxin/Trimethoprim. No biofilm-forming colonies were isolated from cultures. Povidone was found to disrupt the biofilm and increase antibiotic effectiveness, decreasing MBIC and MBEC.
Conclusions :
Most of the patients with keratoprosthesis use some type of contact lens to prevent desiccation of the ocular surface, but at the same time, they serve as a scaffold for bacteria growth and biofilm formation. Ideal antibiotic prophylaxis regimen and disinfecting agents could help prevent biofilm formation and its complications. The use of povidone may enhance the antibiotic response in our patients. This study will help to develop evidence-based guidelines for infectious prophylaxis and contact lens change schedules in patients with K-pro.
This is a 2020 ARVO Annual Meeting abstract.