Molecular typing of vancomycin-resistant Enterococcus faecium with an automated repetitive sequence-based PCR microbial typing system compared with pulsed-field gel electrophoresis and multilocus sequence typing.

Background: Pulsed-field gel electrophoresis (PFGE) is the main typing method used for the molecular typing of vancomycin-resistant Enterococcus faecium (VREfm). However, more rapid and unambiguous typing methods are needed. DiversiLab, a repetitive sequence-based PCR (rep-PCR), offers an alternative method for strain typing.

Methicillin-sensitive Staphylococcus aureus bacteraemia and endocarditis among injection drug users and nonaddicts: host factors, microbiological and serological characteristics.

Background: Endocarditis has been associated with lower mortality and fewer complications among injection drug users (IDUs) than nonaddicts in Staphylococcus aureus bacteraemia (SAB). The better prognosis of IDUs has not been clarified but it has generally been explained by younger age and other host factors. In this study, bacterial strains, their virulence factors, and host immune responses were compared among IDUs and nonaddicts with SAB, including those with and without endocarditis.

Clonality of epidemic methicillin-resistant Staphylococcus aureus strains in Finland as defined by several molecular methods.

In Finland, the incidence of methicillin-resistant Staphylococcus aureus (MRSA) strains has increased ten fold within the last decade. In order to follow the changing epidemiology of MRSA, accurate typing of S. aureus strains is important.

Nationwide trends in molecular epidemiology of methicillin-resistant Staphylococcus aureus, Finland, 1997-2004.

Background: In Finland, the annual number of MRSA notifications to the National Infectious Disease Register (NIDR) has constantly increased since 1995, and molecular typing has revealed numerous outbreak isolates of MRSA. We analyzed the data on MRSA notifications of the NIDR, and MRSA isolates were identified mainly by pulsed-field gel electrophoresis (PFGE) at the National Reference Laboratory (NRL) in Finland during 1997-2004. One isolate representative of each major PFGE type was further characterized by multilocus sequence (MLST)-, staphylococcal cassette chromosome mec (SCCmec)-, and Panton-Valentine leukocidin (PVL)-typing.

Panton-Valentine leukocidin genes and staphylococcal chromosomal cassette mec types amongst Finnish community-acquired methicillin-resistant Staphylococcus aureus strains, 1997-1999.

Methicillin-resistant Staphylococcus aureus (MRSA) strains from Finland covering years 1997-1999 were studied for the presence of Panton-Valentine leukocidin (PVL) gene loci, and the clinically well-defined community-acquired MRSA (CA-MRSA) strains (n = 108) also for staphylococcal chromosomal cassette mec (SCCmec) and multilocus sequence types (MLST). Only a minority (12%) of the CA-MRSA strains contained the PVL gene loci and possessed genotypes formerly described as typical to CA-MRSA strains. The majority of these strains were heterogenous by MLST and pulsed-field gel electrophoresis (PFGE) analysis but, however, harboured the SCCmec cassette type IV.