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Evaluation of fungal and bacterial contaminations of patient-used ocular drops
Mostafa Feghhi1, Ali Zarei Mahmoudabadi, Manijeh Mehdinejad
1Department of Ophthalmology, Imam Khomeini Hospital, Ahvaz, Iran.
Abstract:
The aim of the present study was to investigate the incidence of fungal and bacterial contaminations of in-use eye drop products in the teaching department of ophthalmology, Imam Khomeini Hospital, Ahvaz. Two hundred and eighty seven eye drop bottles were randomly collected at the end of day 1, day 2, day 3, day 4 and day 7 of use. The eye drop residues, swabs from internal caps and droppers were inoculated onto MacConkey agar, blood agar and Sabouraud's dextrose agar. The identification of the recovered organisms was accomplished using standard microbial identification techniques. The incidence of microbial contamination of in-use eye drop products was 17.8%, with the highest rate (24.6%) and the lowest rate (9.0%) noted with day 1 and day 3 samples, respectively. The most contaminated part of the eye drop products was the caps (45.9%) followed by droppers (41.0%) and residual contents (13.1%). Considering mendicants contents, those with pilocarpine (41.7%) had the highest rate of contamination followed by atropine (31.8%), tropicamide (28.6%) and betamethasone (23.3%). Our study revealed the potential risk of contamination of in-use eye drop products in hospitals, but we did not find a direct relationship between usage duration and contamination rate.
Insights
Microbial contamination of in-use eye drops is a significant hospital risk. This study found 17.8% of eye drop bottles contaminated, with caps being the most affected part.
Area of Science:
- Ophthalmology
- Microbiology
- Hospital Infection Control
Background:
- In-use ophthalmic preparations pose a risk for microbial contamination.
- Hospital environments require vigilant monitoring of sterile products.
Purpose of the Study:
- To determine the incidence of fungal and bacterial contamination in in-use eye drop products.
- To identify the most frequently contaminated parts and types of eye drops.
Main Methods:
- Collected 287 in-use eye drop bottles from day 1 to day 7.
- Inoculated residues, caps, and droppers onto MacConkey, blood, and Sabouraud's dextrose agar.
- Identified microorganisms using standard microbial techniques.
Main Results:
- Overall contamination rate was 17.8%, with the highest on day 1 (24.6%) and lowest on day 3 (9.0%).
- Contaminated parts included caps (45.9%), droppers (41.0%), and residual contents (13.1%).
- Pilocarpine (41.7%) and atropine (31.8%) eye drops showed higher contamination rates.
Conclusions:
- In-use eye drops in hospitals present a potential contamination risk.
- No direct relationship was found between usage duration and contamination rate.
- Specific eye drop formulations may be more susceptible to microbial growth.
