Infections à Staphylococcus aureus porteurs du gène codant la leucocidine de Panton-Valentine à l'hôpital: quel statut donner à ces souches?

Abstract

The aim of the present study was to investigate the prevalence Staphylococcus aureus infections carrying Panton-Valentine leukocidin (LPV) genes in our hospital by screening patients that are hospitalised or admitted for consultation, as well as to study the characteristics of these strains and the respectively infected patients. A descriptive and retrospective study over the course of a 14 month period was conducted. The isolates of S. aureus were tested for antimicrobial resistance, in which detection of the virulence gene was performed by way of PCR, such as is the case for gene luk-PV which encoding the LPV. The genetic diversity of the strains carrying gene, luk-PV, was determined by way of pulsed-field gel electrophoresis and by the MLVA (Multiple Loci VNTR Analysis; VNTR, Variable Number of Tandem Repeats) method. 7.14% of the S. aureus isolates carried genes for LPV, which are primarily sourced from surgery, emergency, and outpatient consultation services. The nature of the reported infections is often surface, immediately collected, and more rarely deep. Genotyping revealed three principal clones that were gathering 55% of the strains, which in turn highlighted transmission to the nursing staff. These strains of S. aureus LPV+ have the capacity for diffusion and pathogenicity, which leads to the need to take some specific measures at hospitals: the tracking of the LPV during repeat or deep infections with S. aureus, possibly the search for conveyance and individual measures for the eradication of the strain. Lastly, it is necessary to increase the nursing staff's awareness of the appropriate hygiene measures when they come into contact with these patients.