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Published on: October 20, 2011
Evaluation of the Microbiology of Removed Punctal Plugs and Intracanalicular Devices
Jay J Meyer1, Karissa Culbreath, Edward Ager
1Department of Ophthalmology (J.J.M., N.E., W.C.F., A.M.F.), University of North Carolina, Chapel Hill, NC; Department of Ophthalmology (J.J.M.), University of Auckland, Auckland, New Zealand; Tricore Reference Laboratories (K.C.), Albuquerque, NM; Brooke Army Medical Center (E.A.), San Antonio, TX; Medical College of Wisconsin Department of Ophthalmology (N.E.), Milwaukee, WI; Campbell University School of Medicine (W.C.F.), Lillington, NC; Department of Pathology-Laboratory Medicine (P.G.), University of North Carolina School of Medicine, Chapel Hill, NC; and Department of Ophthalmology (A.M.F.), Duke University, Durham, NC.
Objective:
The purpose of this observational study was to characterize the microorganisms colonizing punctal plugs and intracanalicular stents.
Methods:
Devices were removed from participants who previously underwent placement of punctal plugs for tear insufficiency and lacrimal stents for dacryocystorhinostomy and canalicular reconstruction procedures. After removal of the devices, they were cultured for organisms both with and without sonication to loosen any biofilms or adherent microorganisms. Primary outcome measures included culture positivity, identification of isolated microorganisms, recovery of microorganisms from culture after sonication, and clinical evidence of ocular infection.
Results:
There were no cases of clinical infection. A total of 181 specimens were processed (174 punctal plugs, seven intracanalicular stents), of which 98 (54%) were culture positive. Of the punctal plugs, 92 (52.9%) were culture positive, including 42 with a single organism isolated, whereas 22 yielded two organisms, 7 yielded three organisms, and the remaining 21 yielded a polymicrobial culture with four or more organisms. The most common isolates from punctal plugs were coagulase negative staphylococci (27.6%), diphtheroids (16.4%), and streptococcus viridans (10.2%). Those plugs with polymicrobial culture results grew a mixture of organisms most consistent with skin or upper respiratory flora. Of the intracanalicular stents, 6 (85.6%) were culture positive.
Conclusions:
Punctal plugs and intracanalicular devices can become colonized with bacteria composed of oropharyngeal flora, skin flora, and other rare but potentially significant pathogens.
Insights
Punctal plugs and intracanalicular stents commonly harbor bacteria, including skin and respiratory flora, though clinical infection is rare. This study characterized the microbial colonization of these common ophthalmic devices.
Area of Science:
- Ophthalmology
- Microbiology
- Biomaterials Science
Background:
- Punctal plugs and intracanalicular stents are frequently used in ophthalmic procedures.
- Understanding the microbial colonization of these devices is crucial for assessing potential risks and optimizing patient care.
Purpose of the Study:
- To characterize the types of microorganisms colonizing punctal plugs and intracanalicular stents.
- To determine the prevalence of microbial growth on these devices after removal.
Main Methods:
- Devices were collected from patients post-implantation.
- Cultures were performed with and without sonication to detect adherent microorganisms and biofilms.
- Isolated organisms were identified, and culture positivity rates were assessed.
Main Results:
- 54% of all devices (174 punctal plugs, 7 intracanalicular stents) were culture positive.
- Coagulase-negative staphylococci, diphtheroids, and streptococcus viridans were the most common isolates from punctal plugs.
- Intracanalicular stents showed a high culture positivity rate of 85.6%.
Conclusions:
- Punctal plugs and intracanalicular devices are frequently colonized by bacteria.
- The identified bacteria often consist of oropharyngeal and skin flora.
- While colonization is common, clinical infection associated with these devices was not observed in this study.
