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There is increasing concern regarding the association between certain methicillin-resistant Staphylococcus aureus ( MRSA) genotypes and poor clinical outcome. To assess this issue, a large cohort of 579 subjects with MRSA bacteraemia was prospectively followed from June 2008 to December 2009, in 21 hospitals in Spain. Epidemiology, clinical data, therapy, and outcome were recorded. All MRSA strains were analysed in a central laboratory. Presence of a haematogenous seeding infection was the dependent variable in an adjusted logistic regression model. Of the 579 patients included in the study, 84 (15%) had haematogenous seeding infections. Microdilution vancomycin median MIC ( IQR) was 0.73 (0.38-3) mg/L. Most MRSA isolates ( n = 371; 67%) belonged to Clonal Complex 5 ( CC5) and carried an SCCmec element type IV and agr type 2. Isolates belonging to ST8-agr1- SCCmec IV, ST22-agr1- SCCmec IV and ST228-agr2- SCCmecI-a single locus variant of ST5-accounted for 8%, 9% and 9% of the isolates, respectively. After adjusting by clinical variables, any of the clones was associated with increased risk of haematogenous seeding infections. Higher vancomycin MIC was not identified as an independent risk factor, either. In contrast, persistent bacteraemia ( OR 4.2; 2.3-7.8) and non-nosocomial acquisition (3.0; 1.7-5.6) were associated with increased risk. [ABSTRACT FROM AUTHOR]

Mortality related to methicillin-resistant Staphylococcus aureus ( MRSA) bloodstream infection ( BSI) remains high, despite changes in the epidemiology. To analyze the current predictive factors for mortality we conducted a prospective study in a large cohort of patients with MRSA- BSI from 21 Spanish hospitals. Epidemiology, clinical data, therapy and outcome were recorded. All MRSA strains were analysed, including susceptibility to antibiotics and molecular characterization. Vancomycin MICs ( V- MIC) were tested by the E-test and microdilution methods. Time until death was the dependent variable in a Cox regression analysis. Overall, 579 episodes were included. Acquisition was nosocomial in 59% and vascular catheter was the most frequent source (38%). A dominant PFGE genotype was found in 368 (67%) isolates, which belonged to Clonal Complex ( CC)5 and carried SCCmec IV and agr2. Microdilution V- MIC50 and V- MIC90 were 0.7 and 1.0 mg/L, respectively. Initial therapy was appropriate in 66% of episodes. Overall mortality was observed in 179 (32%) episodes. The Cox-regression analysis identified age >70 years ( HR 1.88), previous fatal disease ( HR 2.16), Pitt score >1 ( HR 3.45), high-risk source ( HR 1.85) and inappropriate initial treatment ( HR 1.39) as independent predictive factors for mortality. CC5 and CC22 ( HR 0.52 and 0.45) were associated with significantly lower mortality rates than CC8. V-MIC ≥1.5 did not have a significant impact on mortality, regardless of the method used to assess it. [ABSTRACT FROM AUTHOR]

Background: Colonization by community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has been found to be markedly more common in HIV-infected individuals in the USA. Studies evaluating the prevalence MRSA colonization in HIV-infected populations in Europe are scarce. The aim of this study was to investigate the prevalence of MRSA colonization in a cohort of HIV-infected patients in Barcelona, Spain. Methods: Nasal and pharyngeal S. aureus carriage was assessed in a random sample of 190 patients from an outpatient HIV clinic. Nasal and pharyngeal swab specimens were obtained for staphylococcal culture from 190 and 110 patients respectively. All MRSA isolates were screened for Panton-Valentine leukocidin (PVL) genes by PCR. Molecular characterization of MRSA isolates was performed by multilocus sequence typing. Data related to HIV infection, healthcare exposure, and previously described risk factors for MRSA were collected from medical records and a questionnaire administered to each patient. Results: The patients' characteristics were as follows: male, 83 %; median (IQR) age, 45 (39-49) years; intravenous drug users, 39 %; men who have sex with men, 32 %; heterosexual, 26 %; CD4 count, 528/µL (IQR 351-740); on antiretroviral therapy, 96 %; and undetectable plasma viral load, 80 %. Sixty-five patients (34 %) were colonized by S. aureus. MRSA colonization was found in 1 % and 2 % of nasal and pharyngeal samples respectively. No PVL positive MRSA strains were detected and all the MRSA isolates belonged to typical hospital-acquired clones. Conclusions: Our data suggest that CA-MRSA colonization is not currently a problem in HIV-infected individuals in our area. [ABSTRACT FROM AUTHOR]

Background: Colonization by community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has been found to be markedly more common in HIV-infected individuals in the USA. Studies evaluating the prevalence MRSA colonization in HIV-infected populations in Europe are scarce. The aim of this study was to investigate the prevalence of MRSA colonization in a cohort of HIV-infected patients in Barcelona, Spain. Methods: Nasal and pharyngeal S. aureus carriage was assessed in a random sample of 190 patients from an outpatient HIV clinic. Nasal and pharyngeal swab specimens were obtained for staphylococcal culture from 190 and 110 patients respectively. All MRSA isolates were screened for Panton-Valentine leukocidin (PVL) genes by PCR. Molecular characterization of MRSA isolates was performed by multilocus sequence typing. Data related to HIV infection, healthcare exposure, and previously described risk factors for MRSA were collected from medical records and a questionnaire administered to each patient. Results: The patients’ characteristics were as follows: male, 83 %; median (IQR) age, 45 (39–49) years; intravenous drug users, 39 %; men who have sex with men, 32 %; heterosexual, 26 %; CD4 count, 528/μL (IQR 351–740); on antiretroviral therapy, 96 %; and undetectable plasma viral load, 80 %. Sixty-five patients (34 %) were colonized by S. aureus. MRSA colonization was found in 1 % and 2 % of nasal and pharyngeal samples respectively. No PVL positive MRSA strains were detected and all the MRSA isolates belonged to typical hospital-acquired clones. Conclusions: Our data suggest that CA-MRSA colonization is not currently a problem in HIV-infected individuals in our area. [ABSTRACT FROM AUTHOR]

Hospital-acquired methicillin-resistant Staphylococcus aureus (MRSA) strains are no longer limited to acute-care hospitals but have now spread to other healthcare settings such as long-term-care facilities (LTCFs), in most of which they are endemic. In Europe, few studies have addressed the MRSA situation in LTCFs. A cross-sectional study to determine MRSA prevalence and factors associated with S. aureus carriage in community LTCF residents is reported here. Nasal and decubitus ulcer cultures were performed for residents of nine community LTCFs. Residents were classified as MRSA carriers, methicillin-susceptible S. aureus carriers and non-carriers. Overall, 1377 nasal swabs and 82 decubitus ulcer cultures were performed. MRSA was isolated from 15.5% and 59.0% of the former and latter, respectively. The prevalence of MRSA colonization was 16.8% (95% CI  14.9–18.8), varying from 6.7% to 35.8% (p <0.001) among LTCFs. Several independent variables were related to MRSA colonization. It is noteworthy that residents in an LTCF with fewer than 150 beds had at least a two-fold higher probability of being MRSA carriers. Modifiable factors were medical devices, decubitus ulcers and previous antibiotic treatment. An age of 85 years or older, a Charlson index ≥2 and transfer from an acute-care facility were non-modifiable factors also related to MRSA colonization. A high MRSA prevalence among residents in community LTCFs in Spain, with great variability among facilities, was found. The factors identified as being associated with MRSA colonization could be prevented by the implementation of several measures. Control strategies need to be coordinated between LTCFs and acute-care hospitals. [ABSTRACT FROM AUTHOR]