Monday, March 12, 2012

Prevalence and Risk Factors for Methicillin-Resistant Staphylococcus aureus Colonization Among Outpatients Undergoing Hemodialysis Treatment

Prevalence and Risk Factors for Methicillin-Resistant Staphylococcus aureus Colonization Among Outpatients Undergoing Hemodialysis Treatment


Jan 2012

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[Article in Turkish]

Source

Denizli State Hospital, Clinic of Infectious Diseases, Denizli, Turkey.

Abstract


Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) is frequent among hemodialysis patients and lead to increased morbidity and mortality rates. It is known that nasal colonization plays an important role for the development ofMRSA infections. The aim of this study was to determine the prevalence and risk factors for MRSA colonization among outpatients undergoing hemodialysis. A total of 466 adult patients (199 female, 267 male; age range: 18-89 years, mean age: 55.8 ± 15.1 years) who were under hemodialysis between September-December 2008 in different health centers at Pamukkale/ Denizli region, Turkey, were included in the study. Swab samples obtained from anterior nares of patients were cultivated on sheep-blood agar and mannitol-salt agar media. The isolates were identified by conventional bacteriological methods. S.aureus strains were isolated from 204 (43.8%) patients and 34 (16.7%) were found methicillin-resistant. Thus the rate of MRSA colonization in hemodialysis patients was detected as 7.3% (34/466). All of the MRSA strains were found susceptible to vancomycin, linezolid and tigecycline, while the resistance rates for the other antimicrobial agents were as follows: 70.6% to azithromycin and claritromycin; 64.7% to erythromycin; %58.8 to clindamycin, gentamicin and trimethoprim-sulfamethoxazole; 55.9% to ciprofloxacin; 44.1% to tetracycline and rifampin; 5.9% to chloramphenicol. Inducible clindamycin resistance in MRSA isolates was %23.5 (8/34), and multidrug resistance rate was 76.5% (26/34). Multivariate analysis revealed that the history of previous hospitalization within a year [odds ratio (OR), 3.426; 95% confidence interval (CI), 1.595-7.361, p= 0.002] and the presence of chronic obstructive lung disease (OR, 5.181; 95% CI, 1.612-16.648, p= 0.006) were independent risk factors for MRSA colonization in this population. A better understanding of the prevalence and risk factors for nasal MRSA colonization among hemodialysis population may hold significant implications for both the treatment strategies and prevention of MRSA infections to establish appropriate infection control measures.


PubMed

Sunday, March 4, 2012

Synergy between oxacillin and manuka honey sensitizes methicillin-resistant Staphylococcus aureusto oxacillin.

Synergy between oxacillin and manuka honey sensitizes methicillin-resistant Staphylococcus aureusto oxacillin.


Mar 2012

Source

Centre for Biomedical Sciences, Cardiff School of Health Sciences, Cardiff Metropolitan University, Western Avenue, Cardiff CF5 2YB, Wales, UK.

Abstract


OBJECTIVES:


Honey is an ancient wound remedy that has recently been introduced into modern clinical practice in developed countries. Manuka honey inhibits growth of methicillin-resistant Staphylococcus aureus (MRSA) by preventing cell division. In Gram-negative bacteria a synergistic interaction between honey and antibiotics has been suggested. We aimed to determine the effect of manuka honey on oxacillin resistance in MRSA.


METHODS:


Inhibition of MRSA by manuka honey and oxacillin separately and in combination was tested by disc diffusion, Etest strips, serial broth dilution, chequerboards and growth curves.


RESULTS:


Manuka honey and oxacillin interacted synergistically to inhibit MRSA. Manuka honey reversed oxacillin resistance in MRSA, and down-regulation of mecR1 was found in cells treated with manuka honey.


CONCLUSIONS:


Microarray analysis showed that exposure of MRSA to inhibitory concentrations of manuka honey resulted in down-regulation of mecR1. Here we demonstrated that subinhibitory concentrations of honey in combination with oxacillin restored oxacillin susceptibility to MRSA. Other honey and antibiotic combinations must now be evaluated.


PubMed

Formal infectious diseases consultation is associated with decreased mortality in Staphylococcusaureus bacteraemia.

Formal infectious diseases consultation is associated with decreased mortality in Staphylococcusaureus bacteraemia.


Mar 2012

Source

Department of Microbiology and Infectious Diseases, PathWest Laboratory Medicine Royal Perth Hospital, Wellington Street, Perth, 6000, Western Australia, Australia, owen.robinson@health.wa.gov.au.

Abstract


To determine the impact of infectious diseases consultation (IDC) in Staphylococcus aureus bacteraemia. All MRSAbacteraemia and a random subset of MSSA bacteraemia were retrospectively analysed. Out of 599 SAB episodes, 162 (27%) were followed by an IDC. Patients with IDC were younger and more frequently intravenous drug users, but fewer resided in a long-term care facility or were indigenous. Hospital length of stay was longer (29.5 vs 17 days, p < 0.001), and endocarditis (19.1% vs 7.3%, p < 0.001) and metastatic seeding (22.2% vs 10.1%, p < 0.001) were more frequent in the IDC group; however, SAPS II scores were lower in the IDC group (27 vs 37, p < 0.001). ICU admission rates in the two groups were similar. The isolate tested susceptible to empirical therapy more frequently in the IDC group (88.9% vs 78.0%, p = 0.003). Seven-day (3.1 vs 16.5%), 30-day (8.0% vs 27.0%) and 1-year mortality (22.2% vs 44.9%) were all lower in the IDC group (all p < 0.001). Multivariate analysis showed that effective initial therapy was the only variable associated with the protective effect of IDC. In patients with SAB, all-cause mortality was significantly lower in patients who had an IDC, because of the higher proportion of patients receiving effective initial antibiotics.


PubMed