The Risk of Microbial Contamination in Multiple-Dose Preservative-Free Ophthalmic Preparations

Area of Science:

• Ophthalmology
• Microbiology
• Pharmaceutical Sciences

Background:

• Multiple-dose preservative-free ophthalmic preparations are susceptible to microbial contamination.
• Hospital ophthalmic preparations exhibit diverse physicochemical properties.
• Understanding these properties is crucial for preventing contamination.

Purpose of the Study:

• To evaluate the association between physicochemical properties and microbial contamination in hospital ophthalmic preparations.
• To assess microbial dynamics and contamination rates in specific ophthalmic formulations.
• To inform safe storage practices for in-use ophthalmic solutions.

Main Methods:

• Investigated microbial dynamics in physiological saline, 0.2% fluconazole, 0.5% vancomycin hydrochloride, and 2% cyclosporine ophthalmic preparations.
• Assessed microbial contamination in patient-used ophthalmic preparations.
• Quantified microbial growth and survival rates post-inoculation.

Main Results:

• Significant growth of Pseudomonas aeruginosa, Burkholderia cepacia, and Serratia marcescens occurred in physiological saline and 0.2% fluconazole.
• All tested microorganisms showed reduced counts in 0.5% vancomycin hydrochloride.
• No microorganisms were detected in 2% cyclosporine after 6 hours.
• Contamination rates were 16.7% for 0.5% vancomycin hydrochloride (Candida spp.) and 0% for 2% cyclosporine.

Conclusions:

• Physicochemical properties significantly influence microbial contamination risk in ophthalmic preparations.
• 2% cyclosporine demonstrated superior antimicrobial properties compared to 0.5% vancomycin hydrochloride.
• Storage methods for in-use ophthalmic preparations must consider formulation-specific properties to ensure safety.