Enterococcus gallinarum carrying the vanA gene cluster: first report in Brazil

Abstract

In 2000, Enterococcus faecalis resistant to vancomycin was first reported at a tertiary hospital in Porto Alegre, southern Brazil. The resistance spread to other hospitals and surveillance programs were established by hospital infection committees to prevent the spread of vancomycin-resistant enterococci. In February 2002, an isolate initially identified at the genus level as Enterococcus was obtained by surveillance culture (rectal swab) from a patient admitted to a hospital for treatment of septic arthritis in the shoulder. The isolate proved to be resistant to vancomycin by the disc diffusion method and confirmed by an E-test resulting in a minimal inhibitory concentration of > or = 256 µg/ml. This isolate was sent to a reference laboratory (Laboratório Especial de Bacteriologia e Epidemiologia Molecular, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, USP) for further study and proved to be an E. gallinarum by the polymerase chain reaction (PCR) using specific primers for the species. Due to the phenotype of unusually high vancomycin resistance, the isolate presumably had the resistance genes (vanA and vanB) and this was confirmed by PCR, which indicated the presence of the vanA gene. A 10.8-kb Tn1546-related transposon was also identified by long-PCR. Interspecies transfer of the vancomycin-resistance gene from the donor E. gallinarum was performed in a successful conjugation experiment in vitro, using E. faecium GE-1 and E. faecalis JH22 as receptors. This is the first report of the detection of a vanA determinant naturally acquired by E. gallinarum in Brazil, indicating the importance of characterizing VRE by both phenotype and genotype methods

Antimicrobial resistance of Enterococcus sp. isolated from the intestinal tract of patients from a university hospital in Brazil

“…In 1997, the prevalence of colonization by these species in another hospital in Brazil was 1.2% (Cereda et al 1997), Canada presented 5% of these species (Toye et al 1997), Lebanon 1.4% (Zouain & Araj 2001), and Kuwait 4.5% (Udo et al 2003). The high prevalence obtained in this study is very important because several studies have reported infection or colonization by E. gallinarum carrying genes that determine high resistance to vancomycin: E. gallinarum vanA in Belgium (Dukta-Malen et al 1994), in Italy (Biavasco et al 2001), in Japan (Takayama et al 2003), and in Brazil (Camargo et al 2004). E. gallinarum vanB in Switzerland (Liassine et al 1998) and Australia (Schooneveldt et al 2000).…”

Rapid detection of Van genes in rectal swabs by real time PCR in Southern Brazil

“…The presence of E. gallinarum containing vanA isolates has already been described in Brazil and deserves special attention in future studies 10 . Discrepant results for the molecular screening were observed in half of these samples.…”

Emergence of the vanA genotype among Enterococcus gallinarum isolates colonising the intestinal tract of patients in a university hospital in Rio de Janeiro, Brazil

“…Owing to the clinical relevance of such resistance markers, studies to determine the possibility of interspecies transfer of this set of resistance genes are needed. Previous studies have demonstrated that the vanA gene can be transferable from E. gallinarum to E. faecalis and E. faecium strains by conjugation in vitro [16,30]. Enterococcal gene transfer and pheromone-responsive systems may be associated with acquired glycopeptide resistance, especially with the VanA phenotype [28].…”

“…Although still rare, high-level acquired vanA-mediated glycopeptide resistance has been described in E. gallinarum and E. casseliflavus recovered in different geographical areas [12][13][14][15][16][17], and natural acquisition of the vanB gene has been associated with E. gallinarum isolates [17][18][19]. Most of the reports are related to faecal colonisation, whilst a few cases of infection have also been documented.…”

“…In Brazil, the first case of faecal colonisation by E. gallinarum carrying the vanA gene was detected in 2002 in a hospital located in Rio Grande do Sul state, in the southern region of the country [16]. The first case of clinical infection by vanA-carrying E. gallinarum in a Brazilian patient also occurred in 2002, in Rio de Janeiro state, in the south-eastern region of the country [20], in a hospital where the presence of VRE (vanA-carrying E. faecalis) was first detected in January 2000.…”