Asymptomatic neurocognitive disorders in patients infected by HIV: fact or fiction?

Neurocognitive disorders are emerging as a possible complication in patients infected with HIV. Even if asymptomatic, neurocognitive abnormalities are frequently detected using a battery of tests. This supported the creation of asymptomatic neurocognitive impairment (ANI) as a new entity. In a recent article published in BMC Infectious Diseases, Magnus Gisslén and colleagues applied a statistical approach, concluding that there is an overestimation of the actual problem. In fact, about 20% of patients are classified as neurocognitively impaired without a clear impact on daily activities. In the present commentary, we discuss the clinical implications of their findings. Although a cautious approach would indicate a stricter follow-up of patients affected by this disorder, it is premature to consider it as a proper disease. Based on a review of the data in the current literature we conclude that it is urgent to conduct more studies to estimate the overall risk of progression of the asymptomatic neurocognitive impairment. Moreover, it is important to understand whether new biomarkers or neuroimaging tools can help to identify better the most at risk population

[Adherence properties and production of slime by staphylococci: relation to pathogenicity]

Among the S. aureus 25/39 are non producing slime and non adherent isolates. These results did not allow a correlation between these properties and pathogenesis. Several different phenotyping systems (biotyping, phage typing, serotyping, antibiotic susceptibility profiling, and plasmid pattern analysis) have been used in an attempt to identify strains of CNS. There is still a need however, for a simple, rapid, and cost effective method of distinguishing true pathogens from simple contaminants. Our results suggest that testing isolates for slime positivity and for adherence property may fulfill this task

A decade-long surveillance of nasopharyngeal colonisation with Streptococcus pneumoniae among children attending day-care centres in south-eastern France: 1999–2008

International audienceThe antimicrobial resistance and serotype distribution of (SP) among children attending day-care centres in south-eastern France were monitored from 1999 to 2008, before and after interventions promoting prudent antibiotic use initiated in 2000 and the availability of pneumococcal conjugate vaccine in 2003. Antibiotic susceptibility and serotypes of SP isolates were determined on nasopharyngeal samples of children aged 3-40 months attending day-care centres, from January to March 1999, 2002, 2004, 2006 and 2008. SP carriage fell from 54% to 45%, and SP with diminished susceptibility to penicillin (PDSP) fell from 34% to 19%. Antibiotic prescriptions dropped from 63% to 38% of children, but third-generation cephalosporins were increasingly prescribed. The overall antibiotic susceptibility increased. Over 90% of the children had received at least one vaccine dose in 2008. Vaccine serotypes 6B, 9V, 19F and 23F (76%) in 1999 were replaced by non-vaccine types (95%) in 2008, among which were 15 (20%), 19A (15%), 23A/B (10%) and 6A (9%). Serotypes 6A, 19A and 15 accounted for over 50% of PDSP strains in 2008 versus 6% in 1999. Children now mostly harbour non-vaccine types; however, PDSP isolates are mainly recruited among these. Vaccine-related benefits may be threatened by combined vaccine- and antibiotic-driven selective pressure

Effect of subinhibitory concentrations of cefamandole and cefuroxime on adherence of Staphylococcus aureus and Staphylococcus epidermidis to polystyrene culture plates

The ability of cefamandole and cefuroxime to inhibit adherence of staphylococci to polystyrene culture plates was tested in an in vitro assay using eight strains each of Staphylococcus aureus and Staphylococcus epidermidis. The results indicated that subinhibitory concentrations of cefamandole and cefuroxime altered the adherence ability of both staphylococcal species, inhibition of adherence being more marked in the presence of cefamandole. It may be important to consider antiadherence properties in association with bactericidal activity when selecting agents for antibiotic prophylaxis

Efficacy of subinhibitory concentration of pefloxacin in preventing experimental Staphylococcus aureus foreign body infection in mice

Adhesion is the first step leading to colonization and infection of a foreign body (FBI). To assess the ability of a subinhibitory concentration (subMIC) of pefloxacin (P) to prevent such infection, an experimental model was developed in Swiss albino mice. Subcuts of polyurethane catheters (Vygon) were placed in the peritoneal cavity of animals and 24 hours later, different inocula of an adherent strain of Staphylococcus aureus (SA) (MIC of P:0.8 mg/l) were injected i.p. Unexposed SA served as controls. Two days later the removed catheters, blood and spleen specimens were quantitatively cultured for bacterial content and identity. Infection was defined as more than 10 CFU/ml of SA recovered. Significant protection of mice, with lower dissemination, was found with inoculum sizes of 10(5) and 10(6). These results suggest that subMICs of P may confer protection against foreign body infection

Effects of subinhibitory concentrations of vancomycin and teicoplanin on adherence of staphylococci to tissue culture plates.

Bacterial adhesion is the first step in infection of medical devices. Staphylococcus aureus and Staphylococcus epidermidis are the pathogens recovered most often. The effects of subinhibitory concentrations of vancomycin and teicoplanin on the adherence of eight clinical strains of S. aureus and eight strains of S. epidermidis to tissue culture plates in vitro were tested. The mean relative inhibitions of adherence at one-fourth and one-eighth the MIC were statistically different for teicoplanin and vancomycin. Slime production seemed not to be involved in adherence