Assessment of the BD EpiCenterTM system for epidemiology and surveillance of hospital acquired infections, exploiting the bacteriology laboratory database

Since the ’70 the exploitation of the clinical bacteriology laboratory databases has been recommended for the surveillance of hospital acquired infections. The EpiCenterTM system that is currently used in our laboratory is very versatile and of great usefulness, despite it requires some improvements in order to enhance the graphic format by which results are reported.The four reports that have been set up represent a good strategic choice for tackling with epidemiologic requests, in particular routine issues raised by clinicians. The reports “Sentinel organisms” and “Recurrence of phenotypes” are intended for real time detection of “alert events”, which can prospect the occurrence of an epidemic case of hospital acquired infections. The report “Endemic events’ monitoring” builds up a follow up trend of endemic events that are already the object of control actions. A retrospective epidemiologic report of isolated organisms can be produced by the “Historical report”. The employment of epidemiology and surveillance reports, together with standard lab procedures, could produce a tremendous amount of data to use in the surveillance and control of hospital acquired infections. Nevertheless, lack of awareness and of collaboration with the laboratory, shown in some cases by the main actors of the surveillance and control of hospital acquired infections, could nullify all of the efforts made by the laboratory

Composites bone cements with different viscosities loaded with a bioactive and antibacterial glass

In this work, three commercial PMMA-based bone cements (high, medium and low viscosities) were enriched with a bioactive and Ag-containing glass to contemporaneously impart bioactive and antibacterial properties. For each formulation, the glass distribution in the polymeric matrix, the bioactivity in simulated body fluid, the silver release, the antibacterial effect and cytotoxicity were evaluated. Morphological and compositional characterizations, by means of scanning electron microscopy and energy-dispersive spectrometry, evidenced good glass dispersion in the polymeric matrix and its appreciable exposition on material surface for all composite cements. The different formulations did not entail the composite ability to induce hydroxyapatite precipitation on their surface (bioactivity) and to release silver ions. The silver release profile was comparable with the rate of infection development; moreover, antibacterial test (inhibition halo evaluation and count of colonies forming units) revealed a significant antibacterial effect towards S. aureus strain. Finally, cytotoxicity test, performed using continuous mouse fibroblast L-929, showed none cytotoxic effect of the multifunctional composite cements for all the polymeric matrix formulations

Antibacterial and bioactive composite bone cements containing surface silver-doped glass particles

A bioactive silica-based glass powder (SBA2) was doped with silver (Ag(+)) ions by means of an ion-exchange process. Scanning electron microscopy (SEM), energy dispersion spectrometry (EDS) and x-ray diffraction (XRD) evidenced that the glass powder was enriched with Ag(+) ions. However, a small amount of Ag2CO3 precipitated with increased Ag concentrations in the exchange solution. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of Ag-SBA2 towards Staphylococcus aureus were also evaluated and were respectively 0.05 mg ml(-1) and 0.2 mg ml(-1). Subsequently, Ag-SBA2 glass was used as filler (30%wt) in a commercial formulation of bone cement (Simplex(™) P) in order to impart both antibacterial and bioactive properties. The composite bone cement was investigated in terms of morphology (using SEM) and composition (using EDS); the glass powder was well dispersed and exposed on the cement surface. Bioactivity tests in simulated body fluid (SBF) evidenced the precipitation of hydroxyapatite on sample surfaces. Composite cement demonstrated antibacterial properties and a compressive strength comparable to the commercial formulation

Antibiotic-free composite bone cements with antibacterial and bioactive properties. A preliminary study

Two bone cements (Palacos R\uae and Palacos LV\uae) based on polymethylmethacrylate (PMMA), clinically used in several cemented prosthetic devices, have been enriched with silver containing bioactive glass powders and compared with the plain commercial ones. The obtained composite cements have been subjected to a preliminary characterization by means of morphological and compositional analyses, compression mechanical tests, bioactivity test (by soaking into simulated body fluids), leaching tests and in vitro antibacterial test (count of colonies forming units, McFarland index evaluation, inhibition zone evaluation). The glass powders appeared uniformly dispersed inside the PMMA matrix and good mechanical properties (in compression) have been reached. The composite cements showed a bioactive behavior (since they developed hydroxyapatite on their surface after soaking in simulated body fluid) and a good antibacterial performance. The release of silver ions, which is the principal reason of antibacterial properties, is mainly reached after the first hours of contact with the leaching solution, as it is expected for a reasonable prevention of bacterial colonization during in vivo applications