Data concerning width and surface of the basement membrane of cortical capillaries in three patients with Alzheimer's disease and five age-matched controls, have been submitted to statistical analysis to ascertain the role of the aging process upon thickening of the basement membrane itself. The analysis showed that there was a significant difference between patients with Alzheimer's disease and controls (P less than 0.01) as to both width and surface of the basement membrane, so suggesting that in these patients aging was not the only factor which thickening of the basement membrane of cortical capillaries was related to.

The fungal concentrations recorded in the present study are comparable to those recorded in other studies conducted in hospital environments and are considerably lower than those seen in other indoor environments that are not air conditioned. These findings demonstrate the effectiveness of air-handling systems in reducing fungal contamination.

Several studies have proposed that the microbiological quality of the air in operating theatres be indirectly evaluated by means of particle counting, a technique derived from industrial clean-room technology standards, using airborne particle concentration as an index of microbial contamination. However, the relationship between particle counting and microbiological sampling has rarely been evaluated and demonstrated in operating theatres. The aim of the present study was to determine whether particle counting could predict microbiological contamination of the air in an operating theatre during 95 surgical arthroplasty procedures. This investigation was carried out over a period of three months in 2010 in an orthopedic operating theatre devoted exclusively to prosthetic surgery. During each procedure, the bacterial contamination of the air was determined by means of active sampling; at the same time, airborne particulate contamination was assessed throughout the entire procedure. On considering the total number of surgical operations, the mean value of the total bacterial load in the center of the operating theatre proved to be 35 CFU/m3; the mean particle count was 4,194,569 no./m3 for particles of diameter ≥0.5 µm and 13,519 no./m3 for particles of diameter ≥5 µm. No significant differences emerged between the median values of the airborne microbial load recorded during the two types of procedure monitored. Particulates with a diameter of ≥0.5 µm were detected in statistically higher concentrations (p<0.001) during knee-replacement procedures. By contrast, particulates with a diameter of ≥5 µm displayed a statistically higher concentration during hip-replacement procedures (p<0.05). The results did not reveal any statistically significant correlation between microbial loads and particle counts for either of the particle diameters considered (≥0.5 µm and ≥5 µm). Consequently, microbiological monitoring remains the most suitable method of evaluating the quality of air in operating theatres.

These results reveal a high level of contamination of aerators by various species of gram-negative opportunists that are potentially very dangerous for immunocompromised patients and, therefore, the need to improve the management of these devices.

No abstract

The emergence and dissemination of carbapenem resistance among Enterobacteriaceae, especially Klebsiella pneumoniae, constitute a serious threat to public health, since carbapenems are the agents of last resort in the treatment of life-threatening infections caused by drug-resistant Enterobacteriaceae. In K. pneumoniae, carbapenem resistance was first reported a decade ago and has subsequently emerged in several countries. One particular group of transmissible plasmid-encoded carbapenemase enzymes, designated K. pneumoniae carbapenemase (KPC), confers carbapenem resistance to K. pneumoniae strains and is rapidly spreading worldwide.In addition to KPC-producing K. pneumoniae, several different metallo-b-lactamaseproducing strains have been identified. These include New Delhi metallo-b-lactamase, Verona integron-encoded metallo-b-lactamase and imipenemase metallo-b-lactamase. Finally, class D carbapenemases, including oxacillin-type carbapenemases, also occur in K. pneumoniae.Carbapenem-resistant K. pneumoniae (CRKP) can cause several types of healthcareassociated infections, including pneumonia, bloodstream infections, wound or surgical site infections, urinary tract infections and meningitis, and is associated with high mortality rates.Multifactorial intervention, including hand hygiene, contact precautions, patient and staff cohorting, minimizing invasive device use, promoting antimicrobial stewardship, screening, active surveillance testing and chlorhexidine bathing, may be an effective strategy for reducing the nosocomial transmission of CRKP. Moreover, the rapid notification of clinical infection whenever CRKP are identified from clinical specimens allows the timely implementation of control measures. ß

No abstract

The hospital water system may constitute a reservoir for microorganisms, such as Pseudomonas aeruginosa, Burkholderia cepacia, Stenotrophomonas maltophilia, Legionella pneumophila, Acinetobacter spp., mycetes, non-tubercular mycobacteria, and so on, which can cause healthcare-associated infections. Indeed, it has been revealed that 20-50% of cases of nosocomial colonization/infection due to P. aeruginosa are sustained by waterborne strains. Waterborne infections can be spread not only through the ingestion of contaminated water but also by contact with or the inhalation of aerosols. Immunocompromised patients are particularly susceptible to infection by such microorganisms, many of which are multi-resistant to antibiotics. Healthcare effects range from colonization of the airways and urinary tracts to bacteraemia and disseminated infections. In 2011, the WHO issued guidelines on the quality of water for human consumption, including hospital water supplies. In risk assessment and management, these guidelines adopt criteria centred on preventive measures rather than remedial action alone. The guidelines recommend the adoption of a Water Safety Plan for water-risk management. By providing safe water, proper implementation of the Water Safety Plan ensures patient safety and reduces costs, in that waterborne infections prolong hospitalisation and increase morbidity, mortality, treatment costs and compensation claims