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Optimized Autologous Serum Eye Drops: Microbial Contamination After Extended Length of Use of Two Different Types of
Frantisek Sanak1,2, Katja Iselin1, Claude Kaufmann1,2
1Department of Ophthalmology, Cantonal Hospital of Lucerne, Lucerne-16, Switzerland.
Purpose:
This study analyzed the contamination rate of autologous serum (AS) eye drops in 2 different eye dropper bottles (glass bottles with a filter-free rubber tip vs. plastic bottles with a one-way-valve) and evaluated patient preference regarding bottle type.
Methods:
In this prospective, comparative, nonrandomized study, 17 patients with severe dry eye disease administered AS eye drops using the standard glass eye dropper bottle and the plastic eye dropper bottle. Patients recorded the date/time of start and end of use. The tip of the eye dropper bottle was cultivated on a chocolate agar plate and the residual content of the bottle in a thioglycolate medium. Patients also filled in a questionnaire regarding bottle preference. The main outcome was microbial contamination of the eye dropper bottle.
Results:
In total, 229 glass and 104 plastic eye dropper bottles were analyzed for microbial contamination. The average duration of use was 3.8 days for glass and 4.1 days for plastic bottles. Tip contamination rates increased proportionally with duration of use and were comparable for both bottle types. Content contamination for glass bottles reached 50% after 2.5 days. For plastic bottles, the content of only 1/104 was contaminated. None of the patients developed clinical symptoms or complications related to bacterial contamination. Overall, 80% of patients preferred the glass bottle.
Conclusions:
Plastic bottles with a filter system preventing backflow of eye drops from the bottle tip, successfully prevented the microbial contamination of AS content inside the bottle over an extended period. Bottle tips were contaminated similarly in both types of bottles.
Insights
Plastic eye dropper bottles with a one-way valve effectively prevented microbial contamination of autologous serum (AS) eye drops, unlike traditional glass bottles. Patient preference leaned towards glass bottles despite contamination risks.
Area of Science:
- Ophthalmology
- Microbiology
- Materials Science
Background:
- Autologous serum (AS) eye drops are used for severe dry eye disease.
- Microbial contamination of eye drops poses a risk to ocular health.
- Standard glass eye dropper bottles may be susceptible to contamination.
Purpose of the Study:
- To compare the microbial contamination rates of autologous serum eye drops in glass versus plastic eye dropper bottles.
- To evaluate patient preference between the two bottle types.
Main Methods:
- A prospective, comparative study involving 17 patients with severe dry eye disease.
- Culturing of eye dropper bottle tips and residual contents.
- Patient questionnaires assessing bottle preference.
Main Results:
- Content contamination occurred in 50% of glass bottles within 2.5 days, versus 1% in plastic bottles.
- Tip contamination rates were similar for both bottle types and increased with duration of use.
- No clinical complications related to contamination were observed in patients.
Conclusions:
- Plastic bottles with a one-way valve system significantly reduce microbial contamination of autologous serum eye drop contents.
- While plastic bottles offer superior microbial protection, 80% of patients preferred the glass bottle type.
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