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The reuse of opthalmic Minims: an unacceptable cross-infection risk?
P Rautenbach1, A Wilson, P Gouws
1Mersey Deanery, Cornwall, UK.
Aims:
The instillation of a combined fluorescein-anaesthetic eye drop is common practice in most ophthalmology clinics. Chauvin Pharmaceuticals produce unpreserved proxymethacaine 0.5% and fluorescein 0.25% in a Minims vial (PFM) intended for single application only. Our aim was to determine whether the reuse of these eye drops for multiple applications has the potential for bacterial transmission.
Methods:
Samples were collected from doctors in general outpatient clinics. Each sample constituted a blood agar plate inoculated with the initial drop of fluid from a PFM as a control. The vial was then used for multiple applications on consecutive patients. One of the last remaining drops was then inoculated onto an alternate marked site on the same plate to serve as the test sample. The samples were immediately transported to the Microbiology laboratory and incubated at 37 degrees C for 48 h. The results were interpreted thereafter by a Microbiologist.
Results:
A total of 41 samples were collected by eight Samplers. In all, 7/41(17%) samples showed growth of normal conjunctiva and lid flora on the test area. These were coagulase negative Staphylococci and Corynebacterium spp.
Conclusions:
The reuse of single application of PFM should be questioned due to the potential risk of transmitting pathogens. A change to a single use only policy would result in a projected threefold increase in the annual budget for these drops.
Insights
Reusing single-application proxymethacaine 0.5% and fluorescein 0.25% (PFM) eye drops risks bacterial transmission. Studies show 17% of reused PFM vials had bacterial contamination, questioning current practices.
Area of Science:
- Ophthalmology
- Microbiology
- Infectious Disease
Background:
- Unpreserved proxymethacaine 0.5% and fluorescein 0.25% (PFM) eye drops are intended for single use in ophthalmology.
- Current clinical practice sometimes involves reusing these single-application vials for multiple patients.
Purpose of the Study:
- To investigate the potential for bacterial transmission through the reuse of single-application PFM eye drops.
- To assess the microbial contamination risk associated with reusing PFM vials.
Main Methods:
- Samples were collected from doctors using PFM vials in outpatient clinics.
- Initial drops served as controls, while subsequent drops from reused vials were tested for bacterial growth.
- Samples were incubated and analyzed in a microbiology laboratory.
Main Results:
- Out of 41 samples, 7 (17%) showed bacterial growth on the test sites.
- Contaminating bacteria included coagulase-negative Staphylococci and Corynebacterium species.
- This indicates bacterial presence after reuse of the single-application vials.
Conclusions:
- Reuse of single-application PFM eye drops poses a significant risk of pathogen transmission.
- Current practices of reusing PFM vials should be re-evaluated to prevent potential infections.
- Implementing a single-use policy for PFM drops is recommended, despite potential budget implications.
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