The polytetrafluoroethylene (PTFE) channel model of cyclic-buildup biofilm and traditional biofilm: The impact of friction, and detergent on cleaning and subsequent high-level disinfection

Cleaning of in-hospital flexible endoscopes: Limitations and challenges

OBJECTIVE

to analyze the cleaning process of gastroscopes, colonoscopes and duodenoscopes in eight in-hospital health services.

METHOD

a cross-sectional study conducted with 22 endoscopes (eight gastroscopes, eight colonoscopes and six duodenoscopes), and microbiological analysis of 60 samples of air/water channels (all endoscopes) and elevator (duodenoscopes), in addition to protein testing. Descriptive statistics with calculation of frequencies and central tendency measures was used in data analysis.

RESULTS

the processing of 22 endoscopes was monitored with microbiological analysis for 60 channels. In the pre-cleaning procedure, in 82.3% (14/17) of the devices, gauze was used in cleaning the insertion tube. Incomplete immersion of the endoscope in detergent solution occurred in 72.3% (17/22) of the cases, and in 63.6% (14/22) there was no standardization of filling-in of the channels. Friction of the biopsy channel was not performed in 13.6% (3/22) of the devices. In the microbiological analysis, 25% (7/32) of the samples from the stored endoscopes were positive for microbial growth (from 2x101 to 9.5x104 CFU/mL), while after processing, contamination was 32% (9/28). Protein residues in the elevator channel were detected in 33% of duodenoscopes.

CONCLUSION

the results indicate important gaps in the stages of pre-cleaning and cleaning of endoscopes that, associated with presence of protein residues and growth of microorganisms of epidemiological importance, indicate limitations in safety of the processing procedures, which can compromise the disinfection processes and, consequently, their safe use among patients subjected to such tests.

Reducing Biofilm Infections in Burn Patients' Wounds and Biofilms on Surfaces in Hospitals, Medical Facilities and Medical Equipment to Improve Burn Care: A Systematic Review

Biofilms in burns are major problems: bacterial communities rapidly develop antibiotic resistance, and 60% of burn mortality is attributed to biofilms. Key pathogens are Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and multidrug-resistant Acinetobacter baumanii. Purpose: identify current and novel interventions to reduce biofilms on patients' burns and hospital surfaces and equipment. Medline and Embase were searched without date or language limits, and 31 possible interventions were prioritised: phages, nano-silver, AgSD-NLs@Cur, Acticoat and Mepilex silver, acetic acid, graphene-metal combinations, CuCo2SO4 nanoparticles, Chlorhexidene acetate nanoemulsion, a hydrogel with moxifloxacin, carbomer, Chitosan and Boswellia, LED light therapy with nano-emodin or antimicrobial blue light + Carvacrol to release reactive oxygen species, mannosidase + trypsin, NCK-10 (a napthalene compound with a decyl chain), antimicrobial peptide PV3 (includes two snake venoms), and polypeptides P03 and PL2. Most interventions aimed to penetrate cell membranes and reported significant reductions in biofilms in cfu/mL or biofilm mass or antibiotic minimal inhibitory concentrations or bacterial expression of virulence or quorum sensing genes. Scanning electron microscopy identified important changes in bacterial surfaces. Patients with biofilms need isolating and treating before full admission to hospital. Cleaning and disinfecting needs to include identifying biofilms on keyboards, tablets, cell phones, medical equipment (especially endoscopes), sinks, drains, and kitchens.

Allium ursinum and Allium oschaninii against Klebsiella pneumoniae and Candida albicans Mono- and Polymicrobic Biofilms in In Vitro Static and Dynamic Models

The present study assesses the in vitro antibiofilm potential activity of extracts of wild Allium ursinum and Allium oschaninii. The active ingredients of the extracts were obtained with a technique named Naviglio (rapid solid-liquid dynamic extraction, RSLDE) which is based on an innovative and green solid-liquid extraction methodology. The extracts were tested against models of mono- and polymicrobial biofilm structures of clinically antibiotic-resistant pathogens, Klebsiella pneumoniae ATCC 10031 and Candida albicans ATCC 90028. Biofilms were studied using a static and a dynamic model (microtiter plates and a CDC reactor) on three different surfaces reproducing what happens on implantable medical devices. Antimicrobic activities were determined through minimum inhibitory concentration (MIC), while antibiofilm activity was assessed by minimum biofilm eradication concentration (MBEC) using a crystal violet (CV) biofilm assay and colony forming unit (CFU) counts. Results showed that both Allium extracts eradicated biofilms of the tested microorganisms well; biofilms on Teflon were more susceptible to extracts than those on polypropylene and polycarbonate, suggesting that when grown on a complex substrate, biofilms may be more tolerant to antibiotics. Our data provide significant advances on antibiotic susceptibility testing of biofilms grown on biologically relevant materials for future in vitro and in vivo applications.