Microbial contamination of contact lens storage cases with the use of different contact lens care solutions and lens materials (original) (raw)
Related papers
2021
Background and objective: The fitting of orthokeratology (ortho-k) and multifocal soft contact lenses (SCL) is becoming increasingly popular worldwide for reducing the rate of myopia progression. However, overnight wear use of lenses and microbial contamination of contact lenses and storage vials has been shown to increase the risk of corneal inflammatory and infiltrative events (CIEs). Therefore, we conducted a pilot study to compare the rate, level, and type of microbial contamination of contact lenses and storage vials when participants wear ortho-k and SCL in combination with a hydrogen-peroxide disinfecting system. Material and Methods: A prospective, single-centre, randomized, crossover study was conducted to evaluate the rate and level of contact lens and storage vials contamination during the use of ortho-k and SCL along with a hydrogen-peroxide disinfecting solution over two 10 day wearing periods. Ocular signs and symptoms were assessed during lens wear at baseline and after each wearing period. In addition, contact lens and storage vials were collected, and the type and amount of microbial contamination were evaluated using viable culture and standard identification methods. Results: Twenty-five adults were enrolled, and 21 completed the study. One (5%) ortho-k lens, five (24%) ortho-k storage vials, one (5%) SCL and one (5%) SCL storage vial were contaminated (P > 0.05), predominantly with Gram-positive bacteria. None of the participants had contamination with both ortho-k and SCL. No significant differences were found between the ocular signs, including conjunctival redness and roughness, or conjunctival or corneal staining (all P > 0.05), irrespective of using ortho-k or SCL. Conclusion: This study provides the first data that directly compares microbial contamination of ortho-K versus SCL in patients using a hydrogen-peroxide disinfection system. However, the overall microbial contamination rate of contact lens storage vials was much lower (30%) than the previously reported study Microbial Bioburden of Orthokeratology and Hydrogel Contact Lenses e20 with ortho-k lens wear. The results support conducting a larger clinical trial designed to understand differences in microbial contamination with different lens materials and modalities.
Eye & Contact Lens: Science & Clinical Practice, 2010
Purpose-A contact lens (CL) can act as a vector for microorganisms to adhere to and transfer to the ocular surface. Commensal microorganisms that uneventfully cohabitate on lid margins and conjunctivae and potential pathogens that are found transiently on the ocular surface can inoculate CLs in vivo. In the presence of reduced tissue resistance, these resident microorganisms or transient pathogens can invade and colonize the cornea or conjunctiva to produce inflammation or infection.
Microbial Contamination of Contact Lens Care Systems
American Journal of Ophthalmology, 1987
We examined the contact lens care systems of 100 asymptomatic patients who used hard or soft contact lenses for correction of refractive errors for the presence of bacteria, fungi, Acanthamoeba, and endotoxin. Of 100 patients, 52 had contaminated contact lens care systems. Sixteen of 126 bottles (13%) of commercial contact lens care solutions were contaminated. Contaminated commercial solutions were opened and used for a longer period of time than uncontaminated solutions. Contamina tion was not found in bottles of preserved commercial solutions that were opened and used for less than 21 days. All 12 bottles of homemade saline were contaminated with bac teria, and Acanthamoeba was isolated from two of these bottles. Pseudomonas was found in the care systems of 12 patients. Bacillus species, which form spores resistant to heat, were found in the care systems of seven patients. Endotoxin, which is also resistant to heat, was detected in nine of 35 care systems (26%) test ed. Potential pathogens were isolated from the conjunctiva of six patients. THE MOST SERIOUS complication associated with contact lens use is microbial keratitis. 18 Factors that may be important in the develop ment of microbial keratitis include the type of lens material, 9 wearing schedule, 310 adherence
World Journal of Advanced Research and Reviews
Introduction: Contact lenses (CLs) are medical or cosmetic devices, comfortable and more convenient alternative to eyeglasses. Eye infection will result when microbes are introduced onto CLs, because defense against microbial invasion in the anterior chamber of the eyes is weak due to the very poor blood supply. Method: The present study investigates hygienic habits, attitudes and practices of thirty CL wearers, toward lens care, that might yield to microbial contamination of CL units through examination of 120 samples (4 items of each CL units) to detect microbial growth and to understand associated factors through a structured questionnaire. Results: Microbial contamination was detected in at least one item of twenty-five CL units (83.3%). None of disinfecting care solutions in original bottles was found contaminated. Incidence of microbial contamination in storage case (Right and Left) and rims of solution bottles was 21 (70%), 17 (56.7%) and 6 (20%) respectively. Eye redness aft...
Contact Lens Case Contamination During Daily Wear of a Silicone Hydrogel Lens
Investigative Ophthalmology & Visual Science, 2010
Purpose. Contamination of contact lens cases has been associated with the production of adverse responses in the eye during contact lens wear. This study aimed to evaluate the contamination rate and types of microbes contaminating cases during use of contact lens disinfecting solutions and silicone hydrogel lenses. Methods. Two hundred thirty-two participants were allocated to one or more groups. The participants wore one or more of three silicone hydrogel lenses and used one or more of four contact lens disinfecting solutions. Cases were collected after use for 1 month and sent for routine microbial testing. The rate of contamination of cases and the types of microbes contaminating cases were evaluated. Results. Between 76 and 92% of all cases were contaminated. Use of different contact lenses did not affect contamination rate or the types of microbes isolated from cases. Use of AQuify (PHMB as disinfectant) was associated with the highest contamination rate (92%; p ϭ 0.015) of cases for any microbe. Level and type of contamination with use of ClearCare (H 2 O 2) was similar to use of PHMB (polyhexamethylene biguanide)-or Polyquat/Aldox-containing solutions. There was no difference in contamination rate of cases by fungi or Gram-positive bacteria, but for Gram-negative bacteria, use of Opti-Free Express (Polyquat and Aldox as disinfectants) resulted in a lower contamination rate (7% vs. 29 to 45%; p Ͻ 0.001). The average number of microbes contaminating a case was significantly less for Opti-Free Express (223 Ϯ 1357 cfu/case) compared with Opti-Free RepleniSH (Polyquat and Aldox as disinfectants; 63,244 Ϯ 140,630 cfu/case; p Ͻ 0.001), driven mostly by differences in numbers of Gram-negative bacteria, particularly contamination by Delftia acidovorans in cases exposed to Opti-Free RepleniSH. Conclusions. Different disinfecting solutions used during storage in cases result in different levels of contamination and contamination by different types of microbes. These differences are not simply because of the types of disinfectants used, suggesting that other excipients in, or formulation of, the solution affect contact lens storage case contamination.
Ophthalmic and Physiological Optics, 2007
Purpose: This study aimed to examine the rates of microbial contamination, and identify contaminants associated with contact lenses and lens care accessories used by a group of young contact lens wearers. Methods: Collected contact lenses, lens cases, and lens care solutions were studied by bacterial culture. Contamination rates of these samples were recorded and compared with those reported in previous studies. Results: Of the samples tested, 9% of lens extracts, 34% of case extracts and 11% of solution samples were contaminated with ocular pathogenic microorganisms. Serratia spp., Staphylococcus aureus and coagulase-negative staphylococci were the most common microorganisms isolated. Lens cases were the most frequently contaminated item. Lens cases also yielded the widest range of bacterial isolates. Contact lenses used by occasional wearers were associated with a higher contamination rate. Using either saline or multipurpose solution to rinse lenses before use appeared to be effective in reducing incidence of contamination. Conclusion: Our findings demonstrate that contact lenses and lens care accessories are not well maintained by contact lens wearers. Regular reviews and reinforcement of lens care procedures for the usage and care of contact lenses and lens care accessories is therefore important and essential.
Journal of clinical microbiology, 2000
Microorganisms, especially gram-negative bacteria, are considered to play a role in the etiology of certain corneal infiltrative events (CIEs) observed during soft contact lens wear. This study explored the possibility of microbial colonization of soft contact lenses as a risk factor leading to CIEs. In a clinical trial conducted from March 1993 to January 1996, 330 subjects wore disposable soft contact lenses on a 6-night extended-wear and disposal schedule. During this period, 4,321 lenses (118 during CIEs; 4,203 during asymptomatic lens wear) were recovered aseptically and analyzed for microbial colonization. A greater percentage of lenses were free from microbial colonization during asymptomatic wear than during CIEs (42 versus 23%; P < 0.0001). The incidence of gram-positive bacteria, gram-negative bacteria and fungi was greater during CIEs than during asymptomatic lens wear (P < 0.05). During asymptomatic lens wear, gram-positive bacteria were isolated most frequently an...
2015
Received 16 April, 2014 Received in revised form 24 May, 2014 Accepted 30 May, 2014 Microbial colonization of contact lens users are more than non-contact lens users due to many factors affecting natural defense mechanism. The presence of a contact lens on the cornea represents a foreign body that can alter tear flow, prevent oxygen and ionic diffusion and cause superficial alterations to the integrity of the epithelial layer. This in turn may render the cornea susceptible to microbial attachment and infection. This work was carried out to study the microbial flora (other than viruses) and factors affecting the microbial colonization of conjunctiva and contact lens storage cases. The study group comprised of randomly selected 93 asymptomatic soft contact lens users attending Medicine OPD for complaints other than eye diseases. One hundred age- and sex-matched healthy non-lens users were included as control. Two swabs each from contact lens storage cases and conjunctiva from study gr...
Contact Lens Case Contamination During Daily Wear of Silicone Hydrogels
Optometry and Vision Science, 2010
Purpose. Contamination of contact lens cases has been associated with the production of adverse responses in the eye during contact lens wear. This study aimed to evaluate the contamination rate and types of microbes contaminating cases during use of contact lens disinfecting solutions and silicone hydrogel lenses. Methods. Two hundred thirty-two participants were allocated to one or more groups. The participants wore one or more of three silicone hydrogel lenses and used one or more of four contact lens disinfecting solutions. Cases were collected after use for 1 month and sent for routine microbial testing. The rate of contamination of cases and the types of microbes contaminating cases were evaluated. Results. Between 76 and 92% of all cases were contaminated. Use of different contact lenses did not affect contamination rate or the types of microbes isolated from cases. Use of AQuify (PHMB as disinfectant) was associated with the highest contamination rate (92%; p ϭ 0.015) of cases for any microbe. Level and type of contamination with use of ClearCare (H 2 O 2 ) was similar to use of PHMB (polyhexamethylene biguanide)-or Polyquat/Aldox-containing solutions. There was no difference in contamination rate of cases by fungi or Gram-positive bacteria, but for Gram-negative bacteria, use of Opti-Free Express (Polyquat and Aldox as disinfectants) resulted in a lower contamination rate (7% vs. 29 to 45%; p Ͻ 0.001). The average number of microbes contaminating a case was significantly less for Opti-Free Express (223 Ϯ 1357 cfu/case) compared with Opti-Free RepleniSH (Polyquat and Aldox as disinfectants; 63,244 Ϯ 140,630 cfu/case; p Ͻ 0.001), driven mostly by differences in numbers of Gram-negative bacteria, particularly contamination by Delftia acidovorans in cases exposed to Opti-Free RepleniSH. Conclusions. Different disinfecting solutions used during storage in cases result in different levels of contamination and contamination by different types of microbes. These differences are not simply because of the types of disinfectants used, suggesting that other excipients in, or formulation of, the solution affect contact lens storage case contamination. (Optom Vis Sci 2010;87:456-464)
Microbial contamination of hydrogel contact lenses
Journal of Applied Microbiology, 1997
1997. Bacterial contamination of contact lenses (CLs) may contribute to CL-related corneal infection and inflammation. T h i s study reports CL biota over time during daily and extended wear. Microbial contamination of a 58Oio water, ionic hydrogel CL and a 38%o water, non-ionic hydrogel CL was evaluated in an Australian and an Indian population. Fifty wearers were repeatedly sampled over 18 months. Overnight CL use did not alter the frequency of positive cultures, nor the spectrum of organisms compared with daily CL wear. T h e r e were no differences in type and frequency of CL contamination between the CL types. Positive cultures were more frequently recovered from the Indian population compared with the Australian population.