A Silicone Ventricular Catheter Coated with a Combination of Rifampin and Trimethoprim for the Prevention of Catheter-related Infections

So-called antiinfective catheters which are generated by incorporation of antimicrobial substances into polymers appear to be effectful devices in the prevention of catheter related infections. Such devices mainly act by prevention of bacterial colonization of the catheter surface rather than by inhibition of adherence. In a preceding study, we developed a rifampin-containing silicone catheter for the prevention of ventricular shunt infection. In the present study, this work was continued with a combination of antimicrobials incorporated in silicone ventricular catheters to reduce the risk of rifampin resistance and to expand the antimicrobial spectrum. We found that the drug release kineti…

Development of a long-lasting ventricular catheter impregnated with a combination of antibiotics.

A ventricular silicone catheter impregnated with a combination of rifampin and a quinolone was developed in order to prevent ventricular shunt related infections. As model substance for the quinolones we used sparfloxacin, because of its specific physicochemical properties resulting in a quantitative detection also in the presence of a second antibiotic. In our study we focused especially on an optimization of the antibiotic release out of the impregnated catheters in order to develop long lasting devices with a broad antimicrobial spectrum. A release-optimized catheter was tested with an in vitro colonization test and additionally with a method developed to examine the spread of bacteria o…

Occurence of vancomycin-resistant Enterococcus faecium in patient isolates and aquatic environment during a period between 2004 and 2010

In vitro evaluation of the biocompatibility of contaminated implant surfaces treated with an Er : YAG laser and an air powder system

Abstract: Titanium platelets with a sand-blasted and acid-etched surface were coated with bovine serum albumin and incubated with a suspension of Porphyromonas gingivalis (ATCC 33277). Four groups with a total of 48 specimens were formed. Laser irradiation of the specimens (n=12) was performed on a computer-controlled XY translation stage at pulse energy 60 mJ and frequency 10 pps. Twelve specimens were treated with an air powder system. After the respective treatment, human gingival fibroblasts were incubated on the specimens. The proliferation rate was determined by means of fluorescence activity of a redox indicator (Alamar Blue® Assay) which is reduced by metabolic activity related to c…

Containment of a Large SARS-CoV-2 Outbreak Among Healthcare Workers in a Pediatric Intensive Care Unit.

Objective Healthcare workers (HCWs) are particularly exposed SARS-CoV-2 because they are critical in preventing viral transmission and treating COVID-19 patients. Within HCWs, personnel of intensive care units (ICUs) are at the forefront of treating patients with a severe course of COVID-19 infection and therefore represent an extremely vulnerable group. Thus, our objective is to contribute to establish means of infection control protecting HCWs in the frontline of the current pandemic. Design An outbreak of SARS-CoV-2 was detected and contained in a pediatric ICU (PICU). The first positive case was identified with a point-of-care diagnostic system on site. Real-time PCR-based testing syste…

Real-time PCR detection of Pseudomonas aeruginosa in clinical and municipal wastewater and genotyping of the ciprofloxacin-resistant isolates

Real-time quantification of Pseudomonas aeruginosa was performed in various wastewater systems including clinical, municipal wastewaters and inflow from a wastewater treatment plant. The highest concentrations of P. aeruginosa-specific targets were detected in clinical wastewaters. Limitations of the detection system resulting from inhibition or cross-reaction were identified. Ciprofloxacin-resistant P. aeruginosa strains were isolated after specific enrichment from clinical and municipal wastewaters. In some cases they were also cultivated from effluent of a wastewater treatment plant, and from its downstream river water. A total of 119 isolates were phenotypically characterized as ciprofl…

Efficacy of NaOCl/H2O2irrigation and GaAlAs laser in decontamination of root canals in vitro

Background and Objectives To investigate the bactericidal effect of an 809 nm semiconductor laser alone, and in combination with NaOCl/H2O2 irrigation in root canals in vitro. Study Design/Materials and Methods A total of 72 human single-rooted teeth extracted for periodontal reasons were included. The crowns were removed, the roots shortened to a length of 12 mm, and the canals enlarged up to an apical size of #50 file. The specimens were autoclaved and incubated with a suspension of Streptococcus sanguinis (ATCC 10556). Laser irradiation was performed on a PC-controlled XY translation stage. A 200 micron optic fiber was used. Twelve specimens were irradiated at a power output of 1.5, 3.0,…

Infections associated with medical devices: pathogenesis, management and prophylaxis.

The insertion or implantation of foreign bodies has become an indispensable part in almost all fields of medicine. However, medical devices are associated with a definitive risk of bacterial and fungal infections. Foreign body-related infections (FBRIs), particularly catheter-related infections, significantly contribute to the increasing problem of nosocomial infections. While a variety of micro-organisms may be involved as pathogens, staphylococci account for the majority of FBRIs. Their ability to adhere to materials and to promote formation of a biofilm is the most important feature of their pathogenicity. This biofilm on the surface of colonised foreign bodies is regarded as the biologi…

Microbiological quality of carbonated drinking water produced with in-home carbonation systems.

The microbiological quality of carbonated water produced with tap water in commercial in-home carbonation systems was determined, the results being discussed in the context of the microbiological quality of the tap water used, the properties of the drink makers, and the procedures of preparation and washing of various parts of the appliance. The last-mentioned data were received from each participant of the study by questionnaire. Escherichia coli, coliforms, fecal streptococci and spore-forming sulphite-reducing anaerobes were used as indicators for the hygienic quality of the water. Tap-water samples were collected according to the usual procedure when filling the carbonating bottle, i.e.…

In vitro efficacy of a Hydrophilic Central Venous Catheter Loaded with Silver to Prevent Microbial Colonization

A method was developed to load the surface of a central venous catheter with silver to prevent bacterial colonization. Silver confers a broad antimicrobial activity with a relatively low risk of resistance. Catheters were incubated with a silver nitrate solution in different concentrations. The solvent, incubation temperature and incubation period were varied to examine the influence on the catheter loading. With increasing incubation temperature, time and concentration of silver nitrate, higher rates of silver elution were observed by atomic absorption spectroscopy. Furthermore, by using ethanol-water as a solvent instead of pure water, the amount of silver bound to the catheter surface wa…

Modern Strategies in the Prevention of Implant-Associated Infections

The application of medical devices either for temporary or permanent use has become an indispensible part of almost all fields of medicine. However, foreign bodies are associated with a substantial risk of bacterial and fungal infections. Implant-associated infections significantly contribute to the still increasing problem of nosocomial infections. To reduce the incidence of such infections, specific guidelines providing evidence-based recommendations and comprising both technological and nontechnological strategies for prevention have been established. Strict adherence to hygienic rules during insertion or implantation of the device are aspects of particular importance. Besides such basi…

Detection of antibiotic-resistant bacteria and their resistance genes in wastewater, surface water, and drinking water biofilms.

Abstract In view of the increasing interest in the possible role played by hospital and municipal wastewater systems in the selection of antibiotic-resistant bacteria, biofilms were investigated using enterococci, staphylococci, Enterobacteriaceae, and heterotrophic bacteria as indicator organisms. In addition to wastewater, biofilms were also investigated in drinking water from river bank filtrate to estimate the occurrence of resistant bacteria and their resistance genes, thus indicating possible transfer from wastewater and surface water to the drinking water distribution network. Vancomycin-resistant enterococci were characterized by antibiograms, and the vanA resistance gene was detect…

Molecular monitoring of inactivation efficiencies of bacteria during pulsed electric field treatment of clinical wastewater

Aims:  The applicability of an alternative wastewater disinfection concept based on the pulsed electric field (PEF) treatment is tested with molecular biology techniques using clinical wastewaters. Methods and Results:  Hospital wastewater was treated with the PEF technology. The inactivation efficiencies of bacteria were successfully monitored with real-time polymerase chain reaction (PCR). As the differentiation between living and dead bacterial cells is important for the determination of the disinfection efficiency, propidium monoazide (PMA) was applied. PMA selectively penetrates cells with compromised membranes and intercalates into the DNA inhibiting a subsequent PCR amplification. Th…

Bactericidal Effect of the Er:YAG Laser on Dental Implant Surfaces: An In Vitro Study

The aim of the in vitro study was to examine the bactericidal effect of an Er:YAG laser on common dental implant surfaces.Seventy-two titanium platelets with 3 different surfaces--sandblasted and acid-etched (SA), titanium plasma-sprayed (TPS), and hydroxyapatite-coated (HA)--were incubated with a suspension of Streptococcus sanguinis (ATCC 10556). Irradiation at pulse energies of 60 and 120 mJ and a frequency of 10 pps was performed on a computer-controlled XY translation stage. After laser treatment the specimens were sonicated and the bacterial growth examined by counting colony forming units on blood agar plates. Temperature elevations during irradiation were investigated using K-type t…

Microbial contamination of anesthetic syringes in relation to different handling habits.

This single-center study prospectively assessed the microbial contamination of anesthetic syringes handled perioperatively under different conditions. We documented high rates of bacterial contamination, with strong but statistically nonsignificant differences between handling groups. Our results identify skin contact as the main source of contamination, and thus we emphasize the impact of proper hand hygiene.