Skin Antisepsis before Surgical Fixation of Extremity Fractures.

BACKGROUND: Studies evaluating surgical-site infection have had conflicting results with respect to the use of alcohol solutions containing iodine povacrylex or chlorhexidine gluconate as skin antisepsis before surgery to repair a fractured limb (i.e., an extremity fracture). METHODS: In a cluster-randomized, crossover trial at 25 hospitals in the United States and Canada, we randomly assigned hospitals to use a solution of 0.7% iodine povacrylex in 74% isopropyl alcohol (iodine group) or 2% chlorhexidine gluconate in 70% isopropyl alcohol (chlorhexidine group) as preoperative antisepsis for surgical procedures to repair extremity fractures. Every 2 months, the hospitals alternated interventions. Separate populations of patients with either open or closed fractures were enrolled and included in the analysis. The primary outcome was surgical-site infection, which included superficial incisional infection within 30 days or deep incisional or organ-space infection within 90 days. The secondary outcome was unplanned reoperation for fracture-healing complications. RESULTS: A total of 6785 patients with a closed fracture and 1700 patients with an open fracture were included in the trial. In the closed-fracture population, surgical-site infection occurred in 77 patients (2.4%) in the iodine group and in 108 patients (3.3%) in the chlorhexidine group (odds ratio, 0.74; 95% confidence interval [CI], 0.55 to 1.00; P = 0.049). In the open-fracture population, surgical-site infection occurred in 54 patients (6.5%) in the iodine group and in 60 patients (7.3%) in the chlorhexidine group (odd ratio, 0.86; 95% CI, 0.58 to 1.27; P = 0.45). The frequencies of unplanned reoperation, 1-year outcomes, and serious adverse events were similar in the two groups. CONCLUSIONS: Among patients with closed extremity fractures, skin antisepsis with iodine povacrylex in alcohol resulted in fewer surgical-site infections than antisepsis with chlorhexidine gluconate in alcohol. In patients with open fractures, the results were similar in the two groups. (Funded by the Patient-Centered Outcomes Research Institute and the Canadian Institutes of Health Research; PREPARE ClinicalTrials.gov number, NCT03523962.).

Decolonization in Nursing Homes to Prevent Infection and Hospitalization.

BACKGROUND: Nursing home residents are at high risk for infection, hospitalization, and colonization with multidrug-resistant organisms. METHODS: We performed a cluster-randomized trial of universal decolonization as compared with routine-care bathing in nursing homes. The trial included an 18-month baseline period and an 18-month intervention period. Decolonization entailed the use of chlorhexidine for all routine bathing and showering and administration of nasal povidone-iodine twice daily for the first 5 days after admission and then twice daily for 5 days every other week. The primary outcome was transfer to a hospital due to infection. The secondary outcome was transfer to a hospital for any reason. An intention-to-treat (as-assigned) difference-in-differences analysis was performed for each outcome with the use of generalized linear mixed models to compare the intervention period with the baseline period across trial groups. RESULTS: Data were obtained from 28 nursing homes with a total of 28,956 residents. Among the transfers to a hospital in the routine-care group, 62.2% (the mean across facilities) were due to infection during the baseline period and 62.6% were due to infection during the intervention period (risk ratio, 1.00; 95% confidence interval [CI], 0.96 to 1.04). The corresponding values in the decolonization group were 62.9% and 52.2% (risk ratio, 0.83; 95% CI, 0.79 to 0.88), for a difference in risk ratio, as compared with routine care, of 16.6% (95% CI, 11.0 to 21.8; P<0.001). Among the discharges from the nursing home in the routine-care group, transfer to a hospital for any reason accounted for 36.6% during the baseline period and for 39.2% during the intervention period (risk ratio, 1.08; 95% CI, 1.04 to 1.12). The corresponding values in the decolonization group were 35.5% and 32.4% (risk ratio, 0.92; 95% CI, 0.88 to 0.96), for a difference in risk ratio, as compared with routine care, of 14.6% (95% CI, 9.7 to 19.2). The number needed to treat was 9.7 to prevent one infection-related hospitalization and 8.9 to prevent one hospitalization for any reason. CONCLUSIONS: In nursing homes, universal decolonization with chlorhexidine and nasal iodophor led to a significantly lower risk of transfer to a hospital due to infection than routine care. (Funded by the Agency for Healthcare Research and Quality; Protect ClinicalTrials.gov number, NCT03118232.).

Proton pump inhibitors alter gut microbiota by promoting oral microbiota translocation: a prospective interventional study.

BACKGROUND: The mechanism by which proton pump inhibitors (PPIs) alter gut microbiota remains to be elucidated. We aimed to learn whether PPI induced gut microbiota alterations by promoting oral microbial translocation. METHODS: Healthy adult volunteers were randomly assigned: PP group (n=8, 40 mg esomeprazole daily for seven days) and PM group (n=8, 40 mg esomeprazole along with chlorhexidine mouthwash after each meal for seven days). Fecal and saliva samples were analysed using 16S ribosomal RNA sequencing. Mouse models were introduced to confirm the findings in vivo, while the effect of pH on oral bacteria proliferation activity was investigated in vitro. RESULTS: Taxon-based analysis indicated that PPI administration increased Streptococcus abundance in gut microbiota (P<0.001), and the increased species of Streptococcus were found to be from the oral site or oral/nasal sites, in which Streptococcus anginosus was identified as the significantly changed species (P<0.004). Microbial source tracker revealed that PPI significantly increased the contribution of oral bacteria to gut microbiota (P=0.026), and no significant difference was found in PM group (P=0.467). Compared to the baseline, there was a 42-fold increase in gut abundance of Streptococcus anginosus in PP group (P=0.002), and the times decreased to 16-fold in PM group (P=0.029). Mouse models showed that combination of PPI and Streptococcus anginosus significantly increased the gut abundance of Streptococcus anginosus compared with using PPI or Streptococcus anginosus only. Furthermore, Streptococcus anginosus cannot survive in vitro at a pH lower than 5. CONCLUSIONS: PPIs altered gut microbiota by promoting oral-originated Streptococcus translocation into gut.

Inhibition of STAT3 by S3I-201 suppress peritoneal fibroblast phenotype conversion and alleviate peritoneal fibrosis.

Peritoneal fibrosis is a common pathological response to long-term peritoneal dialysis (PD) and a major cause for PD discontinuation. Understanding the cellular and molecular mechanisms underlying the induction and progression of peritoneal fibrosis is of great interest. In our study, in vitro study revealed that signal transducer and activator of transcription 3 (STAT3) is a key factor in fibroblast activation and extracellular matrix (ECM) synthesis. Furthermore, STAT3 induced by IL-6 trans-signalling pathway mediate the fibroblasts of the peritoneal stroma contributed to peritoneal fibrosis. Inhibition of STAT3 exerts an antifibrotic effect by attenuating fibroblast activation and ECM production with an in vitro co-culture model. Moreover, STAT3 plays an important role in the peritoneal fibrosis in an animal model of peritoneal fibrosis developed in mice. Blocking STAT3 can reduce the peritoneal morphological changes induced by chlorhexidine gluconate. In conclusion, our findings suggested STAT3 signalling played an important role in peritoneal fibrosis. Therefore, blocking STAT3 might become a potential treatment strategy in peritoneal fibrosis.

Carriage of methicillin-resistant Staphylococcus aureus in children <6 years old: a retrospective follow-up study of the natural course and effectiveness of decolonization treatment.

BACKGROUND: Decolonization treatment of MRSA carriers is recommended in Denmark, except in households with MRSA-positive children <2 years old (wait-and-see approach). OBJECTIVES: To investigate a wait-and-see approach in children 2-5 years old, and the effect of decolonization treatment of MRSA carriage in all children <6 years old. PATIENTS AND METHODS: In this retrospective follow-up study, we included MRSA carriers <6 years old in the Capital Region of Denmark from 2007 to 2021. Data were collected from laboratory information systems and electronic patient records. We divided children into age groups of <2 years or 2-5 years and decolonization treatment versus no treatment. Treatment was chlorhexidine body washes and nasal mupirocin, sometimes supplemented with systemic antibiotics. Children were followed until becoming MRSA free, or censoring. The probability of becoming MRSA free was investigated with Cox regression (higher HRs indicate faster decolonization). RESULTS: Of 348 included children, 226 were <2 years old [56/226 (25%) received treatment] and 122 were 2-5 years old [90/122 (74%) received treatment]. Multivariable analyses did not show a larger effect of decolonization treatment versus no treatment in <2-year-olds (HR 0.92, 95% CI 0.52-1.65) or 2-5-year-olds (HR 0.54, 95% CI 0.26-1.12). Without treatment, 2-5-year-olds tended to clear MRSA faster than <2-year-olds (HR 1.81, 95% CI 0.98-3.37). CONCLUSIONS: We did not find a larger effect of decolonization treatment versus no treatment in children <6 years old, and 2-5-year-olds tended to become MRSA free faster than <2-year-olds. These results support a wait-and-see approach for all children <6 years old, but further studies are needed.

Phenotypic and genotypic determination of resistance to common disinfectants among strains of Acinetobacter baumannii producing and non-producing biofilm isolated from Iran.

BACKGROUND: Nosocomial infections are a global problem in hospitals all around the world. It is considered a major health problem, especially in developing countries. The increase in the patient's stay in hospitals has increased the mortality rate, and consequently, the costs drastically increase. The main purpose of using disinfectants in the hospital environment is to reduce the risk of nosocomial infections. Ethylene diamine tetra acetic acid (EDTA) causes lysis and increases susceptibility to antimicrobial agents in the planktonic form of bacteria. This substance affects the permeability of the outer membrane of bacteria. It also prevents the formation of biofilms by bacteria. MATERIALS AND METHODS: In the current study, 120 isolates of Acinetobacter baumannii (A. baumannii) were confirmed by phenotypic and genotypic methods. Antibiogram was performed and then the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of isolates against 5% sodium hypochlorite, ethanol %70, sayasept-HP 2%, chlorhexidine 2%, dettol 4/8% were evaluated. In addition, the disinfectant effect was re-evaluated with the mixture of EDTA solution. All isolates were examined for biofilm presence by crystal violet staining method in triplicates and repeated three times for each strain. Also for all isolates detection of efflux pump genes (Qac-E, qacE-Δ1, SUG-E) by PCR technique was done. RESULTS: Antibiogram results of A. baumannii showed that 6.7% were Multi-drug-resistant (MDR), and 89.2% were Extensively drug-resistant (XDR) isolates. The highest effect of disinfectants was related to 5% sodium hypochlorite, and the least effect was 70% ethanol. EDTA increases the efficacy of selected disinfectants significantly. The highest prevalence of the efflux pump genes was related to SUG-E (95%) and Qac-E (91.7%), and, the qacE-Δ1 gene with 12.5%. The biofilm production rate was 91.3% among all isolates. CONCLUSION: The best and safest way to disinfect hospital floors and surfaces is to choose the right disinfectants, and learn how to use them properly. In this study, a mixture of disinfectants and EDTA had a significant effect on bactericidal activity. it was found that improper use of disinfectants, especially the use of sub-inhibitory dilutions, increases the resistance of bacteria to disinfectants.

Antibiotic dip and irrigation solutions confer increased antimicrobial efficacy of inflatable penile prosthesis hydrophilic surfaces compared with 0.05% chlorhexidine gluconate.

BACKGROUND: Chlorhexidine gluconate (CHG) (0.05%) has recently been suggested as both a dip for the hydrophilic surface and an irrigation solution in the setting of penile prosthesis (PP) surgery. AIM: The study sought to compare the antimicrobial efficacy of 0.05% CHG with vancomycin and gentamicin (VG) antibiotics as dip and/or irrigation solutions in the setting of a hydrophilic PP surface in vitro. METHODS: Sterile PPs with a hydrophilic coating were obtained. A series of experiments were performed to evaluate the efficacy of normal saline (NS), 0.05% CHG, or VG as dip and/or irrigation solutions to reduce methicillin-sensitive Staphylococcus aureus adhesion to PP surfaces. The 8-mm discs from PPs were incubated in 105 colony-forming units/mL of methicillin-sensitive S aureus for 48 hours, plated, and counted. Disc-diffusion tests were conducted by suspending 6-mm discs for 2 minutes in NS, 0.05% CHG, or VG, then placing them coated side down onto plates streaked with the following organisms: methicillin-sensitive S aureus, S epidermidis, Enterococcus, and Escherichia coli. After 24 hours of growth, zones of inhibition were measured. OUTCOMES: We found average bacterial counts (colony-forming units/mL) and zones of inhibition (mm) following a series of treatment protocols of PP discs. RESULTS: PP discs dipped in VG reduced bacterial adhesion to the implant surface >0.05% CHG (~5.5 log vs ~1.5 log; P < .01). Discs irrigated with either 0.05% CHG or NS removed all dip solution adsorbed to the hydrophilic surface, allowing bacterial growth. VG irrigation adsorbed to the hydrophilic surface even after 0.05% CHG or NS dips, reducing bacterial adherence (~3 log). Dipping and irrigating discs with VG was most effective in reducing adherent bacteria (~5.5 log) and was the only irrigation that showed antimicrobial activity. CLINICAL TRANSLATION: VG, when used both as a prophylactic dip and as an intraoperative irrigation solution for hydrophilic penile implant surfaces, has improved efficacy to 0.05% CHG and NS. STRENGTHS AND LIMITATIONS: This is the first study to compare the use of VG, 0.05% CHG, and NS as prophylactic dips and intraoperative irrigations for hydrophilic penile implant surfaces. Limitations include the use of in vitro studies, which serve as a proxy for in vivo practices and may not be entirely accurate nor translatable clinically. CONCLUSION: We demonstrated the superior efficacy of VG as a combined dip and irrigation solution for hydrophilic penile implant surfaces compared with 0.05% CHG.

Minocycline-rifampin-impregnated penile prosthesis surfaces retain antimicrobial activity following irrigation with 0.05% chlorhexidine gluconate and antibiotic solutions.

BACKGROUND: 0.05% Chlorhexidine gluconate (CHG; Irrisept [IrriMax]) is a commercial wound irrigation solution approved by the Food and Drug Administration that has seen recent adoption in the field of prosthetic urology; however, no study has evaluated whether 0.05% CHG is compatible with the minocycline-rifampin-impregnated surface (InhibiZone) of the AMS 700 penile prosthesis (Boston Scientific). AIM: To evaluate whether 0.05% CHG alters the antibiotic efficacy of the minocycline-rifampin-impregnated penile prosthesis surface. METHODS: Discs (8 mm) were taken by a punch biopsy (Sklar) from sterile penile prosthesis reservoirs whose surfaces had been impregnated with rifampin and minocycline. Discs (n = 10) were suspended in 0.05% CHG, vancomycin and gentamicin, or normal saline for 2 minutes to simulate intraoperative irrigation. Discs were then rinsed in normal saline to remove any unbound solution and incubated with methicillin-sensitive Staphylococcus aureus for 48 hours. Adherent surface bacteria were suspended by shaking in a 0.3% Tween 20 solution, serially diluted, plated onto 3M PetriFilms, and counted. Kirby-Bauer disc diffusion assays were conducted to generalize findings across various organisms. OUTCOMES: Outcomes included (1) bacterial adherence to the implant surface measured as bacterial counts (in colony-forming units per milliliter) and (2) bacterial growth reduction measured as zones of inhibitions (in millimeters). RESULTS: Incubation of implant surfaces in 0.05% CHG did not alter recovered bacterial counts as compared with normal saline and vancomycin/gentamycin. Similarly, within a single bacterial species, 0.05% CHG and vancomycin/gentamycin did not alter zone-of-inhibition measurements in Kirby-Bauer disc diffusion studies. CLINICAL TRANSLATION: This study demonstrates in vitro that 0.05% CHG may be used directly on the minocycline-rifampin-impregnated surface without altering the antibiotic efficacy of the coating. STRENGTHS AND LIMITATIONS: Strengths include that this is the first study to evaluate if 0.05% CHG affected the minocycline-rifampin-impregnated surface. Limitations include the use of in vitro studies, which serve as a proxy for in vivo practices and may not be entirely accurate or translatable in a clinical setting. CONCLUSION: 0.05% CHG does not alter the antimicrobial activity of the minocycline-rifampin-impregnated surface as compared with vancomycin/gentamycin and normal saline in vitro; however, its efficacy in clinical practice remains to be evaluated.

0.05% Chlorhexidine Gluconate Irrigation in Trauma/Emergency General Surgical Laparotomy Wounds Closure: A Pilot Study.

INTRODUCTION: Patients who undergo exploratory laparotomy (EL) in an emergent setting are at higher risk for surgical site infections (SSIs) compared to the elective setting. Packaged Food and Drug Administration-approved 0.05% chlorhexidine gluconate (CHG) irrigation solution reduces SSI rates in nonemergency settings. We hypothesize that the use of 0.05% CHG irrigation solution prior to closure of emergent EL incisions will be associated with lower rates of superficial SSI and allows for increased rates of primary skin closure. METHODS: A retrospective observational study of all emergent EL whose subcutaneous tissue were irrigated with 0.05% CHG solution to achieve primary wound closure from March 2021 to June 2022 were performed. Patients with active soft-tissue infection of the abdominal wall were excluded. Our primary outcome is rate of primary skin closure following laparotomy. Descriptive statistics, including t-test and chi-square test, were used to compare groups as appropriate. A P value <0.05 was statistically significant. RESULTS: Sixty-six patients with a median age of 51 y (18-92 y) underwent emergent EL. Primary wound closure is achieved in 98.5% of patients (65/66). Bedside removal of some staples and conversion to wet-to-dry packing changes was required in 27.3% of patients (18/66). We found that most of these were due to fat necrosis. We report no cases of fascial dehiscence. CONCLUSIONS: In patients undergoing EL, intraoperative irrigation of the subcutaneous tissue with 0.05% CHG solution is a viable option for primary skin closure. Further studies are needed to prospectively evaluate our findings.

Can daily bathing with 4% chlorhexidine + daily chlorhexidine wipe for 1 week be effective in decolonizing Candida auris colonization?

BACKGROUND: Herein, it is aimed to present the decolonizing rates of Candida auris colonized cases after daily bathing with 4% chlorhexidine plus daily cleaning with 4% chlorhexidine wipe for 1 week (will be mentioned as DCHX). METHODS: The study period was from October, 2021, to November, 2022. Inclusion criteria were (i) age > 18, (ii) receiving DCHX, (iii) proven C. auris carrier on auricular, or axillar or inguinal swab surveillance cultures up to 5-day period before DCHX. Cases with three consecutive negative surveillance cultures 3 days apart were considered to be decolonized. RESULTS: A total of 38 cases [14 female, aged 61.8 ± 15.5 years] fulfilled the inclusion criteria. Six (15.8%), 23 (60.1%), and 22 cases (57.8%) were postauricular, inguinal, and axillary culture positive, respectively. Only three cases (7.9%) were triple culture positive. Nine cases (23.7%) had three consequent negative surveillance cultures after DCHX and were considered to be decolonized. There was no significant difference in decolonization rates of concomitant only antibiotic receiving cohort vs. concomitant antifungal + antibiotic receiving cohort (5/16 vs. 2/8, p = 1) were decolonized similarly. Of the nine C. auris decolonized cases, two developed C. auris infection in 30 days follow-up after decolonization. However, 10 (34.5%) of 29 non-decolonized cases developed C. auris infection (p: 0.450) within 30 days after surveillance culture positivity. Over all cohorts, day 30 mortality was 23.7% (9/38). CONCLUSION: In conclusion, based on our observational and relatively small uncontrolled series, it appears that DCHX is not very effective in decolonizing C. auris carriers (especially in cases who are C. auris colonized in > 1 areas), although it is not completely ineffective.

Antifungal efficacy of natural antiseptic products against Candida auris.

Candida auris is an emerging fungal pathogen responsible for healthcare-associated infections and outbreaks with high mortality around the world. It readily colonizes the skin, nares, respiratory and urinary tract of hospitalized patients, and such colonization may lead to invasive Candida infection in susceptible patients. However, there is no recommended decolonization protocol for C. auris by international health authorities. The aim of this study is to evaluate the susceptibility of C. auris to commonly used synthetic and natural antiseptic products using an in vitro, broth microdilution assay. Synthetic antiseptics including chlorhexidine, povidone-iodine, and nystatin were shown to be fungicidal against C. auris. Among the natural antiseptics tested, tea tree oil and manuka oil were both fungicidal against C. auris at concentrations less than or equal to 1.25% (v/v). Manuka honey inhibited C. auris at 25% (v/v) concentrations. Among the commercial products tested, manuka body wash and mouthwash were fungicidal against C. auris at concentrations less than or equal to 0.39% (w/v) and 6.25% (v/v) of products as supplied for use, respectively, while tea tree body wash and MedihoneyTM wound gel demonstrated fungistatic properties. In conclusion, this study demonstrated good in vitro antifungal efficacy of tea tree oil, manuka oil, manuka honey, and commercially available antiseptic products containing these active ingredients. Future studies are warranted to evaluate the effectiveness of these antiseptic products in clinical settings.

Candida auris is an emerging superbug fungus that poses a serious threat to global public health. The excellent antifungal efficacy of natural antiseptics and their commercial hygiene products provide new insights into the development of an alternative decolonization regimen against C. auris.

Phytocannabinoids and gingival inflammation: Preclinical findings and a placebo-controlled double-blind randomized clinical trial with cannabidiol.

OBJECTIVE: The aim of this study was to: (1) evaluate the anti-inflammatory effects of cannabidiol (CBD) on primary cultures of human gingival fibroblasts (HGFs) and (2) to clinically monitor the effect of CBD in subjects with periodontitis. BACKGROUND: The use of phytocannabinoids is a new approach in the treatment of widely prevalent periodontal disease. MATERIALS AND METHODS: Cannabinoid receptors were analyzed by western blot and interleukin production detected using enzyme immunoassay. Activation of the Nrf2 pathway was studied via monitoring the mRNA level of heme oxygenase-1. Antimicrobial effects were determined by standard microdilution and 16S rRNA screening. In the clinical part, a placebo-control double-blind randomized study was conducted (56 days) in three groups (n = 90) using dental gel without CBD (group A) and with 1% (w/w) CBD (group B) and corresponding toothpaste (group A - no CBD, group B - with CBD) for home use to maintain oral health. Group C used dental gel containing 1% chlorhexidine digluconate (active comparator) and toothpaste without CBD. RESULTS: Human gingival fibroblasts were confirmed to express the cannabinoid receptor CB2. Lipopolysaccharide-induced cells exhibited increased production of pro-inflammatory IL-6 and IL-8, with deceasing levels upon exposure to CBD. CBD also exhibited antimicrobial activities against Porphyromonas gingivalis, with an MIC of 1.5 µg/mL. Activation of the Nrf2 pathway was also demonstrated. In the clinical part, statistically significant improvement was found for the gingival, gingival bleeding, and modified gingival indices between placebo group A and CBD group B after 56 days. CONCLUSIONS: Cannabidiol reduced inflammation and the growth of selected periodontal pathogenic bacteria. The clinical trial demonstrated a statistically significant improvement after CBD application. No adverse effects of CBD were reported by patients or observed upon clinical examination during the study. The results are a promising basis for a more comprehensive investigation of the application of non-psychotropic cannabinoids in dentistry.

Effectiveness of a tissue conditioner containing antifungals in a rat model of denture stomatitis.

AIM: This study investigated the effectiveness of a drug-modified tissue conditioner in an animal model of denture stomatitis. METHODS AND RESULTS: Wistar rats wore a Candida albicans-contaminated palatal device for 4 days. Next, nystatin (Nys) or chlorhexidine (Chx) were added to a tissue conditioner in their raw or ß-cyclodextrin-complexed (ßCD) forms at their minimum inhibitory concentrations. As controls, one group was not subjected to any procedure (NC), one group used sterile devices, one group had denture stomatitis but was not treated (DS), and another had the devices relined with the tissue conditioner without the addition of any drug (Soft). After 4 days of treatment, treatment effectiveness was assessed visually, histologically, and through CFU count, and myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) assays. Rats from the Soft, Nys, Nys:ßCD, and Chx groups presented a significant decrease in the microbial load compared with the untreated group. Treatment groups showed lower MPO and NAG activity compared to the non-treated group. CONCLUSIONS: The addition of antifungals to a soft tissue conditioner can be a promising approach for denture stomatitis treatment.

Identification of mechanisms modulating chlorhexidine and octenidine susceptibility in Proteus mirabilis.

AIMS: We aimed to identify mechanisms underlying the tolerance of Proteus mirabilis-a common cause of catheter associated urinary tract infection-to the clinically used biocides chlorhexidine (CHD) and octenidine (OCT). METHODS AND RESULTS: We adapted three clinical isolates to grow at concentrations of 512 µg ml-1 CHD and 128 µg ml-1 OCT. Genetic characterization and complementation studies revealed mutations inactivating the smvR repressor and increasing smvA efflux expression were associated with adaptation to both biocides. Mutations in mipA (encoding the MltA interacting protein) were less prevalent than smvR mutations and only identified in CHD adapted populations. Mutations in the rppA response regulator were exclusive to one adapted isolate and were linked with reduced polymyxin B susceptibility and a predicted gain of function after biocide adaptation. Biocide adaptation had no impact on crystalline biofilm formation. CONCLUSIONS: SmvR inactivation is a key mechanism in both CHD and OCT tolerance. MipA inactivation alone confers moderate protection against CHD, and rppA showed no direct role in either CHD or OCT susceptibility.

Use of ClearGuard HD caps in pediatric hemodialysis patients.

BACKGROUND: Bloodstream infections (BSIs) are a leading cause of hospitalizations and mortality among patients receiving hemodialysis (HD) therapy, especially those with a central venous catheter (CVC) for dialysis access. The use of chlorhexidine impregnated catheter caps (ClearGuard) has been associated with a decrease in the rate of HD catheter-related BSIs (CA-BSIs) in adults; similar data have not been published for children. METHODS: We compared CA-BSI data from participating centers within the Standardizing Care to Improve Outcomes in Pediatric Endstage Kidney Disease (SCOPE) collaborative based on the center's use of ClearGuard caps for patients with HD catheter access. Centers were characterized as ClearGuard (CG) or non-ClearGuard (NCG) centers, with CA-BSI data pre- and post-CG implementation reviewed. All positive blood cultures in participating centers were reported to the SCOPE collaborative and adjudicated by an infectious disease physician. RESULTS: Data were available from 1786 SCOPE enrollment forms completed January 2016-January 2022. January 2020 served as the implementation date for analyzing CG versus NCG center data, with this being the time when the last CG center underwent implementation. Post January 2020, there was a greater decrease in the rate of HD CA-BSI in CG centers versus NCG centers, with a decrease from 1.18 to 0.23 and 0.41 episodes per 100 patient months for the CG and NCG centers, respectively (p = 0.002). CONCLUSIONS: Routine use of ClearGuard caps in pediatric dialysis centers was associated with a reduction of HD CA-BSI rates in pediatric HD patients.

Eligibility and efficacy of a CPC- and CHX-based antiviral mouthwash for the elimination of SARS-CoV-2 from the saliva: A randomized, double-blind, controlled clinical trial.

AIM: This study aimed at investigating the efficacy of a 0.05% cetylpyridinium chloride-0.05% chlorhexidine (CPC-CHX) mouthwash in reducing viral load in the saliva as compared with sterile water. MATERIALS AND METHODS: Forty SARS-CoV-2 positive patients were asked to dispense 4 mL of saliva. Half the patients rinsed for 60 s with 15 mL CPC-CHX, and the remaining patients rinsed with sterile water (control). Four millilitres of saliva were collected after 15, 30 and 60 min after rinsing. Quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA) specific for SARS-CoV-2 nucleocapsid protein were performed. For ELISA, the intact (representing the active virus) to total virus load (I/T) was calculated. RESULTS: SARS-CoV-2 copy numbers/mL from RT-qPCR tended to decrease in the control group, whereas in the CPC-CHX group, an increase was observed after T30. However, mixed linear model analysis revealed no statistical differences between groups (p = .124), time points (p = .616) and vaccinated or non-vaccinated patients (p = .953). Similarly, no impact of group (p = .880), time points (p = .306) and vaccination (p = .711) was observed for I/T ratio values. CONCLUSIONS: Within the limitation of this study, there was no evidence that the intervention reduced salivary SARS-CoV-2 viral load during the course of 60 min. Therefore, commonly used pre-procedural rinsing might not be clinically relevant.

In situ and in vitro evaluation of two antiseptics for blood bank based on chlorhexidine gluconate/isopropyl alcohol and povidone-iodine.

BACKGROUND: Poor disinfection is the main cause of blood contamination, so its elimination is key to limiting the entry of bacteria into the collection system. With the advancement of antiseptic technology, antiseptics with sterile, disposable applicators are now available. AIM: To evaluate in situ two antiseptics (with and without applicators) for blood banks and to demonstrate in vitro antiseptic activity on bacterial biofilms of importance in transfusion medicine. METHODS: Antiseptic A (2% sterile solution of chlorhexidine gluconate/70% isopropyl alcohol provided with applicator) and bulk antiseptic B (10% povidone-iodine) were evaluated. The deferred blood donor arms were subjected to disinfection with antiseptics A and B and the contralateral arms were cultured to determine the baseline bacterial load (control). Antiseptic activity was assessed by ANOVA and logaritmic reduction values (LRV) and percentage reduction values (PRV) were calculated. Finally, the in vitro activity of antiseptic A was analyzed by confocal laser scanning microscopy (CLSM) on biofilm models. RESULTS: Prior to disinfection tests, commensal and clinically important bacteria were identified; antiseptic A showed post-disinfection bacterial growth rates of zero compared to controls (p < 0.0001). The frequency of bacterial growth with antiseptic B was 74%. A significant difference was identified between both antiseptics, where antiseptic A showed higher activity (p < 0.5468). LRV and PRV were 0.6-2.5/100% and 0.3-1.7/66.7-99.7% for antiseptics A and B, respectively. Through CLSM, disinfectant A (without applicator) showed lower in vitro antiseptic activity on the tested biofilms at the exposure times recommended by the manufacturer. CONCLUSIONS: Sterile solution of chlorhexidine gluconate/isopropyl alcohol with applicator showed advantages disinfection in deferred blood donors over povidone-iodine.

Resistance to Chlorhexidine and Benzalkonium Chloride in E. Coli ST131, A. Baumannii, and P. Aeruginosa Isolates.

BACKGROUND: The goal was to assess the antimicrobial efficacy of two commonly used biocides, chlorhexidine, and benzalkonium chloride, against MDR isolates of Pseudomonas aeruginosa, Acinetobacter baumannii, and Escherichia coli ST131, as well as the prevalence of resistance genes. METHODS: MIC of chlorhexidine and benzalkonium chloride and their effects on both the planktonic phase and biofilm were determined. Finally, the presence of genes responsible for resistance to quaternary ammonium compounds was investigated by PCR. RESULTS: No significant relationship was observed between the presence of resistance genes and different concentrations of quaternary ammonium compounds (benzalkonium chloride). There was no association between biofilm formation and the presence of resistance genes. CONCLUSIONS: Chlorhexidine digluconate and benzalkonium chloride at appropriate concentrations could prevent biofilm formation.

Influence of Chairside Simulated Adjustment (Finishing and Polishing) Protocol and Chlorhexidine Mouthwash Immersion on Color Stability and Translucency of 2 and 3 Preshaded Multilayered Monolithic Zirconia.

BACKGROUND Preshaded monolithic zirconia (MLZ) is reported to have high translucency. This study aimed to assess the effect of chlorhexidine gluconate (ChG) mouthwash on color and translucency parameter (TP) of 2 different preshaded MLZ dental ceramics after clinical adjustment. MATERIAL AND METHODS Two MLZ disk-shaped specimens [NPM (Nacera Pearl Multi-Shade) (n=72) and CZM (Ceramill Zolid FX Multilayer)] (n=72) were simulated for clinical adjustment, finished, and polished using 2 adjustment kits [recommended kit, third-party kit: Diasynt Plus and SUN (n=12 each)] and later immersed in ChG mouthwash (Avohex) for 2 weeks. Difference in color (ΔE) and TP (Y) were calculated using the CIELab formula after measuring the coordinates (Lab) with a colorimeter. Individual changes in color and TP were assessed on the Clinical acceptance (perceptible) threshold (CAT/CPT) and Translucency perception threshold (TPT), respectively. Differences between the 2 ceramics were assessed using one-way ANOVA and post hoc tests, with all differences considered significant at P<0.05. RESULTS NPM and CZM differed in color at baseline despite having the same Vita shade combination. Between the 2 preshaded MLZ ceramics, NPM showed significant changes in color when adjusted with a third-party kit. Chlorhexidine produced changes in color and TP that were designated as clinically perceptible (ΔE=1.0 to 3.3) on the CAT/CPT and TPT scales, irrespective of the adjustment kit used. ChG produced the least or no changes in glazed MLZ specimens. CONCLUSIONS ChG mouthwash, whenever prescribed for preshaded MLZ restoration, should be adjusted prior to final glazing to avoid clinical adjustments that adversely affects color and translucency of the restoration.

Effect of Dentin Contamination with Hemostatic Agents and Cleaning Techniques on Bonding with Self-Adhesive Resin Cement.

BACKGROUND Dentin contamination with hemostatic agents before bonding indirect restorations negatively affects the bond strength. However, the consensus on which materials could be used to clean contamination of hemostatic agents has not been explored. The aim of this study was to assess the effect of Katana Cleaner applied on the surface of dentin contaminated with hemostatic agents on the shear bond strength (SBS) of self-adhesive resin cement by comparing it with three other surface cleaners. MATERIAL AND METHODS Ninety dentin specimens were divided into a no contamination group (control) (n=10), 4 groups contaminated with 25% aluminum chloride (Viscostat Clear) (n=40), and 4 groups contaminated with 20% ferric sulfate (Viscostat) (n=40). Subsequently, 4 different cleaners were used for each contamination group (water rinse, phosphoric acid, chlorhexidine, and Katana Cleaner). Then, self-adhesive resin cement was directly bonded to the treated surfaces. All specimens were subjected to 5000 thermal cycles of artificial aging. The shear bond strength was measured using a universal testing machine. RESULTS Two-way analysis of variance showed that the contaminant type as the main factor was statistically non-significant (p=0.655), cleaner type as the main factor was highly significant (p<0.001), and interaction between the contaminant and cleaner was non-significant (p=0.51). The cleaner type was the main factor influencing the bond strength. Phosphoric acid and chlorhexidine showed better performance than Katana Cleaner. CONCLUSIONS Cleaning dentin surface contamination with phosphoric acid and chlorhexidine had better performance than with Katana Cleaner.