In order to evaluate the value of bacterial cultures taken from the throat, 266 patients with MRSA were retrospectively assessed. At the time when MRSA was first detected in the patient, the most frequent sites positive for MRSA were a skin lesion (110 patients, 41%), the anterior nares (109 patients, 41%), and the throat (102 patients, 38%). In 26%, 17%, and 17% of the patients, a skin lesion, the anterior nares, and the throat, respectively, were the only site where MRSA was seen. In 123 patients cultured for MRSA because of a close contact with an already known MRSA patient, 65 patients (53%) were positive for MRSA in their throat and in 40 patients (33%), throat was the only sample site with MRSA at the time when the patient was found to be MRSA positive. 146 of the 266 patients (55%) were colonized with MRSA in the throat any time throughout the period they were MRSA positive. We conclude that throat is an important reservoir for MRSA and that samples taken from the throat should be included in screening patients for MRSA.

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Summary. Eleven strains of Staphylococcus lugdunensis from different clinical sources were investigated for their ability to bind 12'I-labelled collagen (Cn) type I and IV, fibronectin (Fn), vitronectin (Vn), laminin (Lm), fibrinogen (Fg), thrombospondin, plasminogen (glu-and lysform) and human IgG. All the strains bound these proteins, although a higher degree of binding was obtained for Cn types I and IV and IgG with mean values of 36 YO, 32 YO and 26 YO binding. respectively. In tests with proteins immobilised on latex beads in a particle agglutination assay, eight of the 11 strains bound Cn type I and seven bound Fg, whereas no strain bound immobilised IgG. Binding to immobilised Cn-I, Fg, Lm and Vn was abolished when the bacterial cells were treated with proteases or heat, indicating cell-surface receptors with protein characteristics. Cell-surface extracts of S . lugdunensis 2342 were able to totally inhibit binding of the homologous strain and S . aureus Cowan 1 to latex-immobilised proteins Cn-I, Lm, Vn, Fn and Fg. The binding of '"I-labelled Cn IV by S. lugdunensis 2342, was heat sensitive, whereas the binding to S. auieus Cowan 1 was heat resistant. The strains gave negative results in tests for the presence of protein A with a S. aureus protein A gene probe and with sensitised red blood cells. No production of heat-stable nuclease (TNase) could be detected by monoclonal antibodies against TNase or by the polymerase chain reaction with an oligonucleotide sequence from S . aureus TNase as primer. When the cell surface characters of the S. lugdunensis strains were studied, five were found to be hydrophobic and negatively charged. four hydrophilic and positively charged and two hydrophobic with positive net charge. lntroduc tionCoagulase-negative staphylococci (CNS) are well recognised as opportunist pathogens causing infections in neonates and neutropenic patients.' They are the most important pathogens in infections associated with intravascular catheters and grafts, peritoneal catheters and prostheses in various organs.' With the recent description of two new species of CNS, Staph?.-lo~~occ~us luqduimsis and S. sclde !'fc.ri,3 there are at present 24 species of CNS. S . epidemviiclis, S. huernolyficws and S. .s~~?rc~~~12.ticIrs are the species isolated most frequently from human infections.' C'ougufase-positive staphylococci, i.e., S. mreus, are more virulent than CNS.' Numerous studies have focused on presumptive virulence factors of S . aureus, and latterly on those of CNS.' Of these factors, only protein A and coagulase are consistently absent in CNS. The presence of heat-stable nuclease is characteristic: of coagulase-positive staphylococci but has not been ascribed any role in pathogenicity.' All other toxin>. enzymes and outer-membrane proteins of S. U14Wli.S have been detected in CNS strains with varying

IntroductionLyme borreliosis (LB) is the most common tick transmitted disease in Europe. The diagnosis of LB today is based on the patient´s medical history, clinical presentation and laboratory findings. The laboratory diagnostics are mainly based on antibody detection, but in certain conditions molecular detection by polymerase chain reaction (PCR) may serve as a complement.AimThe purpose of this study was to evaluate the analytical sensitivity, analytical specificity and concordance of eight different real-time PCR methods at five laboratories in Sweden, Norway and Denmark.MethodEach participating laboratory was asked to analyse three different sets of samples (reference panels; all blinded) i) cDNA extracted and transcribed from water spiked with cultured Borrelia strains, ii) cerebrospinal fluid spiked with cultured Borrelia strains, and iii) DNA dilution series extracted from cultured Borrelia and relapsing fever strains. The results and the method descriptions of each laboratory were systematically evaluated.Results and conclusionsThe analytical sensitivities and the concordance between the eight protocols were in general high. The concordance was especially high between the protocols using 16S rRNA as the target gene, however, this concordance was mainly related to cDNA as the type of template. When comparing cDNA and DNA as the type of template the analytical sensitivity was in general higher for the protocols using DNA as template regardless of the use of target gene. The analytical specificity for all eight protocols was high. However, some protocols were not able to detect Borrelia spielmanii, Borrelia lusitaniae or Borrelia japonica.

Conventional methods for the identification of human-pathogenic aerococci to the species level are not reliable. We show that matrix-assisted laser desorption ionization-time of flight mass spectrometry correctly identifies aerococci to the species level and that it can be used to identify aerococci with high specificity in the diagnostic clinical microbiology laboratory.A erococci make up a genus of bacteria that are increasingly recognized as human pathogens. The two most clinically important aerococcal species are Aerococcus urinae and Aerococcus sanguinicola, which can cause urinary tract infections (1, 2), bacteremia (3, 4), and infective endocarditis (4-6). Aerococci are facultative anaerobic, Gram-positive, and catalase-negative bacteria. Colonies on blood agar resemble alpha-hemolytic streptococci, but on Gram staining, they appear as clusters like staphylococci. Consequently, misidentification of aerococci in the clinical microbiology laboratory commonly occurs (1, 7). Commercially available methods such as Vitek 2 and API-strep, as well as colony morphology and biochemical tests, are unable to safely separate aerococci from other bacteria or differentiate aerococcal species from each other (1, 8). Secure identification of aerococci has relied on sequencing of the 16S rRNA gene. A newly introduced method for identification to the species level in clinical microbiology is matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). It has been shown to be a reliable and fast method for the identification of commonly isolated bacteria in the clinical microbiological laboratory (9, 10). These studies, in which bacterial strains were prospectively collected from clinical samples, indicate that MALDI-TOF MS has the potential to replace conventional identification techniques. However, the accuracy of MALDI-TOF MS identification of bacterial species that are uncommon in clinical samples, such as aerococci, needs to be further evaluated. In a recent study, a collection of well-characterized catalase-negative, Gram-positive cocci including 35 aerococcal strains (of which 27 were A. urinae, 5 were A. sanguinicola, 2 were Aerococcus viridans, and 1 was Aerococcus christensenii) was subjected to MALDI-TOF MS analysis (11).Analysis of each isolate was performed first with Biotyper version 2.0 and then with an extension of the database. All of the A. urinae and A. sanguinicola isolates were correctly identified to the species level, and high scores were obtained especially with an extended database. Herein we evaluate the usefulness of MALDI-TOF MS for the correct identification of A. urinae and A. sanguinicola in a clinical setting by defining both the sensitivity and the specificity of the method.To define the sensitivity of the method, expressed as the proportion of actual aerococci that are correctly identified, all urine isolates at the two routine diagnostic laboratories of clinical microbiology in Malmö and Lund, University and Regional Laboratories, Region Skåne, Sweden, were p...