Disinfection methods of dental unit waterlines contamination: a systematic review.

Background. Severe contamination of dental unit waterlines was found in healthcare settings. The benefits of decontamination methods are controversial. The aim of this review was to systematically evaluate disinfection methods in contamination control of dental unit waterlines.Methods. The terms 'dental unit waterline(s) or DUWL(s) or dental unit water line(s)' were searched through PubMed, Cochrane Library, Embase, Web of Science and Scopusup to 31 May 2021. The DUWLs' output water was incubated on R2A agar at 20-28 °C for 5-7 days to evaluate heterotrophic mesophilic bacteria. The risk of bias was evaluated by a modified Newcastle-Ottawa quality assessment scale.Results. Eighteen papers from the literature were included. One study indicated that water supply played a crucial role in disinfecting DUWLs. Three studies indicated that flushing decreased bacteria counts but did not meet the American CDC standard (500 c.f.u. ml-1). All chlorine- and peroxide-containing disinfectants except sodium hypochlorite in one of 15 studies as well as three mouthrinses and citrus botanical extract achieved the standard (≤500 c.f.u. ml-1). The included studies were of low (1/18), moderate (6/18) and high (11/18) quality.Conclusion. Independent water reservoirs are recommended for disinfecting DUWLs using distilled water. Flushing DUWLs should be combined with disinfections. Nearly all the chlorine-, chlorhexidine- and peroxide-containing disinfectants, mouthrinses and citrus botanical extract meet the standard for disinfecting DUWLs. Alkaline peroxide would lead to tube blockage in the DUWLs. Regularly changing disinfectants can reduce the risk of occurrence of disinfectant-resistant strains of microbes.

Grape seed extract against Aichi virus infectivity in model foods and contact surfaces.

Aichi virus (AiV) is an enteric virus that affects humans and is prevalent in sewage waters. Effective strategies to control its spread need to be explored. This study evaluated grape seed extract (GSE) for: a) antiviral potential towards AiV infectivity at 37 °C and room temperature (RT); b) antiviral behavior in model foods (apple juice (AJ) and 2% fat milk) and also simulated gastric environments; and c) potential application as a wash solution on stainless steel surfaces. GSE at 0.5 mg/mL decreased AiV suspensions containing ~4.75 log PFU/mL to titer levels that were not detected after 30 s at both 37 °C and RT. Infectious AiV titers were not detected after 5 min treatment with 1 mg/mL GSE at 37 °C in AJ. GSE at 2 mg/mL and 4 mg/mL in 2% fat milk decreased AiV after 24 h by 1.18 and 1.57 log PFU/mL (4.75 log PFU/mL to 2.86 and 3.25 log PFU/mL), respectively. As a surface wash, GSE at 1 mg/mL after 30 s decreased AiV to undetectable levels under clean conditions. With organic load (mimicking unclean conditions), 2 and 4 mg/mL GSE reduced AiV after 5 min by 1.13 and 1.71 log PFU/mL, respectively. Overall, GSE seems to be a promising antiviral agent against AiV at low concentrations and short contact times.

Keyboard Contamination in Intensive Care Unit: Is Cleaning Enough? Prospective Research of In Situ Effectiveness of a Tea Tree Oil (KTEO) Film.

After the SARS-CoV-2 pandemic, disinfection practices and microbial load reduction have become even more important and rigorous. To determine the contamination of keyboard surface and the relative risk to transfer healthcare-associated pathogens to susceptible patients, as it frequently happens in Intensive Care Unit (ICU), a standard keyboard (SK), a cleanable keyless keyboard (KK) with smooth surface and a standard keyboard coated with a 3 M Tegaderm® film added with active essential oil (tea tree oil) (KTEO) were tested. S. aureus, including MRSA strains, were detected in ICU, with values ranging from 15% to 57%. Gram negative strains belonging to the Enterobacteriaceae family were also found with values ranging from 14% to 71%. Similar Gram positive and Gram negative strains were found on all surfaces, but with low percentage, and only environmental bacteria were detected using the settling plates method. The Microbial Challenge Test performed on KTEO showed high rates of decrease for all the pathogens with statistical significance both at 24 and 48 h (p = 0.003* and p = 0.040*, respectively). Our results suggest that the use of KTEO may be a feasible strategy for reducing the transmission of pathogens in health care setting and may be complementary to surface cleaning protocols.

Safety in the use of ultrasound in rheumatology during the COVID-19 Pandemic. Spanish Society of Rheumatology positioning paper. / Seguridad en el uso de la ecografía en reumatología durante la pandemia COVID-19. Documento de posicionamiento de la Sociedad Española de Reumatología.

Ultrasound is a widely implemented imaging modality in rheumatology practice that implies a great interaction between patient and professional. The COVID-19 pandemic requires a change in our clinical practice, through the adoption of new strategies that allow comprehensive care for our patients, guaranteeing the safety of both patients and healthcare professionals. OBJETIVE: Our objective was to develop practical recommendations, agreed among a panel of experts, on the use and safety of rheumatological ultrasound during the COVID-19 pandemic. METHODS: We performed a narrative review of the available literature. Based on the literature review, we produced preliminary recommendations that were subsequently agreed among a panel of experts using the Delphi methodology with a 1-5 Likert scale. Agreement for each recommendation was considered if 75% of the panel members scored the item ≥4 on the Likert scale. RESULTS: 5 overarching principles and 28 recommendations were issued and agreed among the panel. Group consensus was achieved in 100% of items. CONCLUSIONS: The document provides useful information about preventive measures in the practice of ultrasound in rheumatology in times of a COVID-19 pandemic based on the experience and literature available to date.

Antimicrobial activity of copper surfaces against biofilm formation by Salmonella Enteritidis and its potential application in the poultry industry.

As a consequence of developing antimicrobial resistance to disinfectants, copper, which exhibits antimicrobial activity, has been studied as a possible alternative to the use of stainless steel surfaces. The aim was to evaluate the antimicrobial activity of copper surfaces in preventing biofilm formation by Salmonella Enteritidis and to determine their corrosive capacity. Strains of S. Enteritidis were incubated at 4 °C, 12 °C, and 25 °C with 1 cm2 coupons of electrolytic copper (99.9% Cu), brass (70% Cu), copper coated with tin, and stainless steel (control). A planktonic cell-suspension assay was used, followed by serial dilutions and bacterial counts. The corrosion test was performed with two disinfectants: benzalkonium chloride and sodium hypochlorite (100, 200, and 400 ppm). There was a significant reduction in biofilm production (log10 CFU cm-2) on the copper (2.64 at 4 °C, 4.20 at 12 °C, 4.56 at 25 °C) and brass (2.79 at 4 °C, 3.49 at 12 °C, 4.55 at 25 °C) surfaces compared to the control (5.68 at 4 °C, 5.89 at 12 °C, 6.01 at 25 °C). The antimicrobial surfaces showed uniform corrosion similar to that of surfaces generally used. These results demonstrated the effectiveness of copper surfaces in reducing S. Enteritidis and suggest they can be used as a complementary antimicrobial to control for this pathogen.

kEDTA Sample Contamination: A Reappraisal.

BACKGROUND: Potassium EDTA (kEDTA) contamination of serum samples is common, causing spurious hyperkalemia, hypozincemia, and hypocalcemia that if unrecognized may adversely affect patient care. Gross kEDTA contamination is easy to detect, but identification of spurious electrolytes due to small amounts of contamination requires measurement of serum EDTA. We validated an EDTA assay on the Abbott Architect and reassessed its value in identifying kEDTA contamination and in studying mechanisms for contamination. METHODS: Within- and between-batch imprecision, linearity, recovery, interference, and carryover were assessed. Serum supplemented with k2EDTA plasma, to mimic sample contamination, was used to study its effect on potassium, calcium, zinc, magnesium, and alkaline phosphatase. Our current laboratory protocol for identification of kEDTA contamination, based on measurement of serum calcium, was compared to that of EDTA measurement. RESULTS: The EDTA assay displayed acceptable performance characteristics. Hemoglobin was a positive interferent. EDTA was detectable in serum contaminated with 1% (v:v) k2EDTA plasma. An increase in serum potassium of 0.54 mmol/L (11.9%) was observed at a measured EDTA concentration of 0.19 mmol/L, equivalent to 3.2% (v:v) contamination. At this EDTA concentration reductions were also observed in zinc (71%), calcium (1%), alkaline phosphatase (ALP) (4%), and magnesium (2.4%). The serum EDTA assay detected contamination in 31/106 patient samples with hyperkalemia (potassium ≥6.0mmol/L), 20 of which were undetected by the current laboratory protocol. CONCLUSIONS: The EDTA assay displayed acceptable performance, with the ability to reliably measure EDTA at low concentrations. Only a small amount of kEDTA causes significant spurious hyperkalemia and is only reliably detected with EDTA measurement.

Avaliação microbiológica de superfícies em terapia intensiva: reflexões sobre as estratégias preventivas de infecções nosocomiais / Microbiological evaluation of surfaces in intensive care: thinking about nosocomial infection prevention strategies / Evaluación microbiológica de superficies en cuidados intensivos: reflexiones sobre las estrategias preventivas de infecciones nosocomiales

Objetivo: determinar o perfil microbiológico de bactérias isoladas e identificadas nos leitos e bombas infusoras na unidade de terapia intensiva de um hospital universitário do Estado do Rio de Janeiro. Método: foram coletadas nove amostras de grades das camas dos pacientes e oito de teclados de bomba infusora de uma unidade de terapia intensiva, em outubro de 2014, delimitando-se uma área de 100cm² como parâmetro para ambas as coletas. As amostras foram coletadas através de swabs estéreis que foram umedecidos e transportados em Carry & Blair. Os microrganismos foram isolados, classificados e depois testados em relação à resistência antimicrobiana. Resultados: o gênero Staphylococcus coagulase negativa foi o mais prevalente. Os testes de suscetibilidade a antimicrobianos apontaram alguns destes Staphylococci como multirresistentes. Conclusão: chama-se atenção para a necessidade de ampliação do debate multiprofissional sobre questões de segurança hospitalar, apresentando a educação permanente como um possível caminho de sucesso no controle das infecções.

Objective: to determine the microbiological profile of bacteria isolated and identified from beds and infusion pumps in the intensive care unit of a university hospital in Rio de Janeiro state. Method: nine samples were collected from patients' bed side rails and eight from infusion pump keypads in an intensive care unit in October 2014. An area of 100cm² was delimited as the sampling parameter. Samples were collected using sterile swabs, which were wetted and transported with Cary-Blair. The microorganisms were isolated, classified, and then tested for antimicrobial resistance. Results: coagulase-negative Staphylococcus was the most prevalent type. Antimicrobial susceptibility testing indicated some of these Staphylococci were multi-drug resistant. Conclusion: multi-professional discussion of hospital safety issues must be expanded, and continuing professional development emerges as one possible pathway to success in nosocomial infection control.

Objetivo: determinar el perfil microbiológico de bacterias aisladas e identificadas en las camas y las bombas de infusión en la unidad de terapia intensiva de un hospital universitario de Rio de Janeiro. Método: se recolectaron nueve muestras de rejas de camas de pacientes y ocho de paneles de las bombas de infusión de una unidad de terapia intensiva, en octubre de 2014, delimitandose un área de 100 cm2 como parámetro para ambas recolecciones. Se recolectaron las muestras a través de swabs estériles que fueron humedecidos y transportados en Carry y Blair. Los microorganismos fueron aislados, clasificados y después probados repecto a la resistencia antimicrobiana. Resultados: el género Staphylococcus coagulasa negativo fue el más prevalente. Las pruebas de susceptibilidad a antimicrobianos mostraron algunos Staphylococci como resistentes a múltiples fármacos. Conclusión: se señala la necesidad de ampliación del debate entre los profesionales de la salud, sobre cuestiones de seguridad hospitalaria, presentando la educación permanente como un posible camino de éxito en el control de las infecciones.

A Novel Protocol Obviates Endoscope Sampling for Carbapenem-Resistant Enterobacteriaceae: Experience of a Center with a Prior Outbreak.

BACKGROUND: Numerous published outbreaks, including one from our institution, have described endoscope-associated transmission of multidrug-resistant organisms (MDROs). Individual centers have adopted their own protocols to address this issue, including endoscope culture and sequestration. Endoscope culturing has drawbacks and may allow residual bacteria, including MDROs, to go undetected after high-level disinfection. AIM: To report the outcome of our novel protocol, which does not utilize endoscope culturing, to address our outbreak. METHODS: All patients undergoing procedures with elevator-containing endoscopes were asked to permit performance of a rectal swab. All endoscopes underwent high-level disinfection according to updated manufacturer's guidance. Additionally, ethylene oxide (EtO) sterilization was done in the high-risk settings of (1) positive response to a pre-procedure risk stratification questionnaire, (2) positive or indeterminate CRE polymerase chain reaction (PCR) from rectal swab, (3) refusal to consent for PCR or questionnaire, (4) purulent cholangitis or infected pancreatic fluid collections. Two endoscopes per weekend were sterilized on a rotational basis. RESULTS: From September 1, 2015 to April 30, 2016, 556 endoscopy sessions were performed using elevator-containing endoscopes. Prompted EtO sterilization was done on 46 (8.3%) instances, 3 from positive/indeterminate PCR tests out of 530 samples (0.6%). No CRE transmission was observed during the study period. Damage or altered performance of endoscopes related to EtO was not observed. CONCLUSION: In this pilot study, prompted EtO sterilization in high-risk patients has thus far eliminated endoscope-associated MDRO transmission, although no CRE infections were noted throughout the institution during the study period. Further studies and a larger patient sample will be required to validate these findings.

Microwave decontamination of eyelid warming devices for the treatment of meibomian gland dysfunction.

PURPOSE: The role of bacteria in meibomian gland dysfunction is unclear, yet contamination of compresses used as treatment may exacerbate this condition. This study therefore determined the effect of heating on bacteria on two forms of compress. METHODS: Cotton flannels and MGDRx EyeBags (eyebags) were inoculated by adding experimental inoculum (Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa; one species for each set of 3 eyebags and flannels). One of each were then randomised in to 3 groups: no heating (control); therapeutic (47.4±0.7°C); or sanitisation (68±1.1°C). After treatment, bacteria cell numbers were calculated. The experiment was repeated in triplicate. RESULTS: There was a statistically significant difference between each treatment with the eyebag for S. aureus (control=7.15±0.11logC/ml, therapeutic heating=5.24±0.59logC/ml, sanitisation heating=3.48±1.43logC/ml; P<0.001) and S. pyogenes (7.36±0.13, 5.73±0.26, 4.75±0.54; P<0.001). P. aeruginosa also showed a significant reduction (P<0.001) from control (6.39±0.34) to therapeutic (0.33±0.26) and sanitisation (0.33±0.21), but the latter were similar (P=1.000). For the flannels, there was significant difference between each treatment for S. aureus (6.89±0.46, 3.96±1.76, 0.42±0.90; P<0.001). For S. pyogenes, there was a significant reduction (P<0.001) from control (7.51±0.10) to therapeutic (5.91±0.62) and sanitisation (5.18±0.8), but the latter were similar (P=0.07). For P. aeruginosa, there was a significant difference (P<0.001) from control (7.15±0.36) to sanitisation (5.83±0.44); but not to therapeutic (6.84±0.31) temperatures (P=0.07). CONCLUSIONS: Therapeutic heating produces a significant reduction in bacteria on the eyebags, but only sanitisation heating appears effective for flannels. However, patients should be advised to heat the eyebag to sanitisation temperatures on initial use.

Staphylococcus aureus and community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in and around therapeutic whirlpools in college athletic training rooms.

CONTEXT: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a leading cause of skin and soft tissue infection in the nonhospitalized community. Care of the athletes in athletic training rooms is specifically designed with equipment tailored to the health care needs of the athletes, yet recent studies indicate that CA-MRSA is still prevalent in athletic facilities and that cleaning methods may not be optimal. OBJECTIVE: To investigate the prevalence of Staphylococcus aureus and CA-MRSA in and around whirlpools in the athletic training room. DESIGN: Cross-sectional study. SETTING: National Collegiate Athletic Association Division I university. PATIENTS OR OTHER PARTICIPANTS: Student-athletes (n = 109) consisting of 46 men (42%) and 63 women (58%) representing 6 sports. MAIN OUTCOME MEASURE(S): Presence of MRSA and Staphylococcus aureus in and around the whirlpool structures relative to sport and number of athletes using the whirlpools. RESULTS: We identified Staphylococcus aureus in 22% (n = 52/240) of the samples and MRSA in 0.8% (n = 2/240). A statistically significant difference existed between the number of athletes using the whirlpool and the presence of Staphylococcus aureus in and around the whirlpools (F(2,238) = 2.445, P = .007). However, Staphylococcus aureus was identified regardless of whether multiple athletes used a whirlpool or no athletes used a whirlpool. We did not identify a relationship between the number of athletes who used a whirlpool and Staphylococcus aureus or MRSA density (P = .134). CONCLUSIONS: Staphylococcus aureus and MRSA were identified in and around the whirlpools. Transmission of the bacteria can be reduced by following the cleaning and disinfecting protocols recommended by the Centers for Disease Control and Prevention. Athletic trainers should use disinfectants registered by the Environmental Protection Agency to sanitize all whirlpools between uses.

Is it possible to sanitize athletes' shoes?

CONTEXT: Footwear should be designed to avoid trauma and injury to the skin of the feet that can favor bacterial and fungal infections. Procedures and substances for sanitizing the interior of shoes are uncommon but are important aspects of primary prevention against foot infections and unpleasant odor. OBJECTIVE: To evaluate the efficacy of a sanitizing technique for reducing bacterial and fungal contamination of footwear. DESIGN: Crossover study. SETTING: Mens Sana basketball team. PATIENTS OR OTHER PARTICIPANTS: Twenty-seven male athletes and 4 coaches (62 shoes). INTERVENTION(S): The experimental protocol required a first sample (swab), 1/shoe, at time 0 from inside the shoes of all athletes before the sanitizing technique began and a second sample at time 1, after about 4 weeks, April 2012 to May 2012, of daily use of the sanitizing technique. MAIN OUTCOME MEASURE(S): The differences before and after use of the sanitizing technique for total bacterial count at 36 °C and 22 °C for Staphylococcus spp, yeasts, molds, Enterococcus spp, Pseudomonas spp, Escherichia coli , and total coliform bacteria were evaluated. RESULTS: Before use of the sanitizing technique, the total bacterial counts at 36 °C and 22 °C and for Staphylococcus spp were greater by a factor of 5.8 (95% confidence interval [CI] = 3.42, 9.84), 5.84 (95% CI = 3.45, 9.78), and 4.78 (95% CI = 2.84, 8.03), respectively. All the other comparisons showed a reduction in microbial loads, whereas E coli and coliforms were no longer detected. No statistically significant decrease in yeasts (P = .0841) or molds (P = .6913) was recorded probably because of low contamination. CONCLUSIONS: The sanitizing technique significantly reduced the bacterial presence in athletes' shoes.

Evaluation of two disinfection/sterilization methods on silicon rubber-based composite finishing instruments.

PURPOSE: To evaluate the effectiveness of disinfection/sterilization methods and their effects on polishing capacity, micomorphology, and composition of two different composite fiishing and polishing instruments. METHODS: Two brands of finishing and polishing instruments (Jiffy and Optimize), were analyzed. For the antimicrobial test, 60 points (30 of each brand) were used for polishing composite restorations and submitted to three different groups of disinfection/sterilization methods: none (control), autoclaving, and immersion in peracetic acid for 60 minutes. The in vitro tests were performed to evaluate the polishing performance on resin composite disks (Amelogen) using a 3D scanner (Talyscan) and to evaluate the effects on the points' surface composition (XRF) and micromorphology (MEV) after completing a polishing and sterilizing routine five times. RESULTS: Both sterilization/disinfection methods were efficient against oral cultivable organisms and no deleterious modification was observed to point surface.

Strategies to prevent biofilm-based tympanostomy tube infections.

OBJECTIVE: To review the potential contributory role of biofilms to post-tympanstomy tube otorrhea and plugging as well as the available interventions currently utilized to prevent biofilm formation on tympanostomy tubes. DATA SOURCES: A literature review was performed utilizing the MEDLINE/Pubmed database from 1980 to 2013. REVIEW METHODS: Electronic database was searched with combinations of keywords "biofilm", "tympanostomy tube", "ventilation tube", and "post-tympanostomy tube otorrhea". RESULTS: Two of the most common sequelae that occur after tympanostomy tube insertion are otorrhea and tube occlusion. There is an increased evidence supporting a role for biofilms in the pathogenesis of otitis media. In this review, we have shown a multitude of novel approaches for prevention of biofilm associated sequelae of otitis media with effusion. These interventions include (i) changing the inherent composition of the tube itself, (ii) coating the tubes with antibiotics, polymers, plant extracts, or other biofilm-resistant materials, (iii) tubal impregnation with antimicrobial compounds, and (iv) surface alterations of the tube by ion-bombardment or surface ionization. CONCLUSION: Currently, there is not one type of tympanostomy tube in which bacteria will not adhere. The challenges of treating chronic post-tympanostomy tube otorrhea and tube occlusion indicate the need for further research in optimization of tympanostomy tube design in addition to development of novel therapies.

Effect of antibiotic drops on adverse events during extended lens wear.

PURPOSE: Overnight lens wear is associated with increased lens contamination and risk of developing a corneal infiltrate or infectious event. Antibacterial lenses have been proposed as a potential strategy for reducing lens contamination. A proof-of-principle study was conducted to investigate what effect control of potential pathogens, through the use of antibiotic eye drops, would have on the incidence of corneal infiltrative events (CIEs) and on the ocular microbiota and lens contamination. METHODS: This is a prospective, open-label, controlled, parallel-group, 1-month clinical study in which 241 subjects were dispensed with lotrafilcon A silicone hydrogel lenses for 30 days of continuous wear. Subjects were randomized into either test (moxifloxacin 0.5%) or control (rewetting solution) group. One drop was instilled into each eye on waking and before sleeping, while lenses were on-eye. Follow-ups were conducted after one night and 1 month. Lid margin swabs were taken at baseline and at 1 month and worn lenses were aseptically collected at 1 month. RESULTS: The incidence of CIEs was not significantly different between the test (2.6%) and control (3.9%) groups (p = 0.72). Microorganism levels from the test group swabs were significantly lower than those from the control group (p = 0.001). Gram-positive bacteria were less frequently recovered from lower lid swabs from the test group (39.6% vs. 66.0% [p < 0.001], test vs. control, respectively) or from contact lens samples (1.9% vs. 10.5% [p = 0.015], test vs. control, respectively), but there was no difference in gram-negative bacteria (GNB). Corneal infiltrative events were associated with higher levels of lens contamination (p = 0.014) and contamination of lenses with GNB (CIE: 7.3% vs. 0.6% [p = 0.029], GNB contamination vs. no GNB contamination, respectively). DISCUSSION: Twice-daily antibiotic instillation during continuous wear of lenses did not significantly influence the rate of inflammatory events. Corneal infiltrative events were associated with higher levels of lens contamination in general and with contamination by GNB specifically.

Formalin disinfection of biopsy needle minimizes the risk of sepsis following prostate biopsy.

PURPOSE: We describe a simple and effective method to reduce the risk of infection after prostate biopsy. MATERIALS AND METHODS: A total of 1,642 consecutive prostate biopsy procedures during a 4-year period (2008 to 2012) were included in the study. Inclusion criteria consisted of pre-biopsy negative urine culture, bisacodyl enema and fluoroquinolone antibiotics (3 days). Formalin (10%) was used to disinfect the needle tip after each biopsy core. All patients were monitored for post-biopsy infection. The rate of infection was compared to that of a historical series of 990 procedures. Two ex vivo experiments were conducted to test the disinfectant effectiveness of formalin against fluoroquinolone resistant Escherichia coli, and another experiment was performed to quantitate formalin exposure. RESULTS: Post-biopsy clinical sepsis with positive urine and blood cultures (quinolone resistant E. coli) developed in 2 patients (0.122%). Both patients were hospitalized, treated with intravenous antibiotics and had a full recovery without long-term sequelae. Mild uncomplicated urinary infection developed in 3 additional patients (0.183%). All were treated with outpatient oral antibiotics and had a complete recovery. The overall rate of urinary infection and sepsis using formalin disinfection was approximately a third of that of a prior series (0.30% vs 0.80%, p=0.13). Ex vivo experiments showed a complete lack of growth of fluoroquinolone resistant E. coli on blood and MacConkey agars after exposure to formalin. The amount of formalin exposure was negligible and well within the safe parameters of the Environmental Protection Agency. CONCLUSIONS: Formalin disinfection of the biopsy needle after each prostate biopsy core is associated with a low incidence of urinary infection and sepsis. This technique is simple, effective and cost neutral.

Identification and susceptibility to multipurpose disinfectant solutions of bacteria isolated from contact lens storage cases of patients with corneal infiltrative events.

Corneal infiltrative events (CIEs) are being reported with increasing frequency in lens wearers and may be related to specific multipurpose disinfecting solution (MPDS), contact lens type or bacterial bio-burden. Here, the efficacy of MPDS's against bacteria from contact lens storage cases (CLSC) of patients with CIEs was investigated. Eighteen CLSC from patients with CIEs were cultured. All reported using the same MPDS based on PQ-1+Aldox+nonanoyl-EDTA prior to experiencing CIEs. Bacteria were identified and tested for sensitivity to MPDS-1 and three other MPSDs. 16/18 CLSC (89%) contained bacterial counts of ≥10(4)-10(8)/mL. Achromobacter spp. was most frequently identified and was found in 11/18 cases (61%). This was followed by 4/18 (22%) Stenotrophomonas maltophilia, 3/18 (17%) Serratia marcescens, 3/18 (17%) Delftia spp., 2/18 (11%) Elizabethkingia spp., 2/18 (11%) Chryseobacterium indologenes and 1/18 Sphingobacterium spiritivorum. Acanthamoeba was not isolated. All of the Achromobacter strains were resistant to MPDS-1 with <1log10 kill up to 14 days exposure and the solution also showed reduced efficacy against the other isolates at the manufacturer's recommended disinfection time of 6h. Two strains of S. maltophilia and Delftia spp. grew in the solution over 14 days. Factors responsible for causing adverse events such as CIEs in contact lens wearers remain unclear. However, the presence of significant bio-burden in the contact lens storage case and lens may initiate an immunological response resulting in CIEs either directly or through the release of endotoxins (e.g. lipopolysaccharides) from the bacterial outer cell membrane.