Antimicrobial susceptibility of 3931 organisms isolated from intensive care units in Canada: Canadian National Intensive Care Unit Study, 2005/2006.

We tested the in vitro activity of 15 antimicrobials against Gram-positive cocci and 12 antimicrobials against Gram-negative bacilli versus 3931 isolates (20 most common organisms) obtained between September 1, 2005, and June 30, 2006, from 19 intensive care units (ICUs) across Canada. The most active (based upon MIC only) agents against methicillin-resistant Staphylococcus aureus and methicillin-resistant Staphylococcus epidermidis were dalbavancin, daptomycin, linezolid, tigecycline, and vancomycin with MIC(90) (microg/mL) of 0.06 and < or =0.

Antimicrobial-resistant pathogens in intensive care units in Canada: results of the Canadian National Intensive Care Unit (CAN-ICU) study, 2005-2006.

Between 1 September 2005 and 30 June 2006, 19 medical centers collected 4,180 isolates recovered from clinical specimens from patients in intensive care units (ICUs) in Canada. The 4,180 isolates were collected from 2,292 respiratory specimens (54.8%), 738 blood specimens (17.

Dalbavancin and telavancin: novel lipoglycopeptides for the treatment of Gram-positive infections.

Two glycopeptide analogues of vancomycin and teicoplanin have been developed with improved pharmacokinetic/pharmacodynamic parameters. Dalbavancin was derived from teicoplanin, and telavancin is a derivative of vancomycin. The half-life of dalbavancin in humans is 147-258 h (6-11 days) allowing for weekly administration.

Increasing genetic relatedness of ciprofloxacin-resistant Streptococcus pneumoniae isolated in Canada from 1997 to 2005.

The genetic relatedness of ciprofloxacin-resistant Streptococcus pneumoniae isolates collected from 1997 to 2002 (n = 82) and 2003 to 2005 (n = 123) was compared by pulsed-field gel electrophoresis (PFGE). Increased genetic homogeneity among the isolates from 2003 to 2005 (cluster analysis; P < 0.001) appeared to be due to expansion of existing clonal groups and to introduction of new PFGE types.

Low prevalence of VRE gastrointestinal colonization of hospitalized patients in Manitoba tertiary care and community hospitals.

Objective: To determine the prevalence of vancomycin-resistant enterococci (VRE) bowel colonization in hospitalized patients in Manitoba who had stool specimens collected for Clostridium difficile toxin and/or culture testing.

Design: Two tertiary care and five community hospitals in Winnipeg and three rural Manitoba community hospitals participated in this study. From January 1 to December 31, 1997 stool specimens, one per patient, submitted to hospital microbiology laboratories for C difficile toxin and/or culture testing were screened for VRE on colistin-nalidixic acid-vancomycin (6 microg/mL) (CNAV) agar plates.

Pyogenic liver abscess caused by hypermucoviscous Klebsiella pneumoniae.

Community-acquired primary pyogenic liver abscess (PLA) caused by Klebsiella pneumoniae is an emerging infectious entity, with cases reported in the scientific literature over the past 15 y mainly from Taiwan and Asia, but also from Europe and North America. We describe a case of PLA caused by the hypermucoviscous, K1 capsular serotype of Klebsiella pneumoniae in a Canadian man and highlight the unique features of this increasingly common cause of liver abscess.

Macrolide resistance mechanisms among Streptococcus pneumoniae isolated over 6 years of Canadian Respiratory Organism Susceptibility Study (CROSS) (1998 2004).

Background: Resistance to macrolides in Streptococcus pneumoniae arises primarily due to Erm(B) or Mef(A). Erm(B) typically confers high-level resistance to macrolides, lincosamides and streptogramin B (MLS(B) phenotype), whereas Mef(A) confers low-level resistance to macrolides only (M phenotype). The purpose of this study was to investigate the incidence of macrolide resistance mechanisms in Canadian isolates of S.

Piperacillin-tazobactam: a beta-lactam/beta-lactamase inhibitor combination.

Piperacillin-tazobactam is a beta-lactam/beta-lactamase inhibitor combination with a broad spectrum of antibacterial activity that includes Gram-positive and -negative aerobic and anaerobic bacteria. Piperacillin-tazobactam retains its in vitro activity against broad-spectrum beta-lactamase-producing and some extended-spectrum beta-lactamase-producing Enterobacteriaceae, but not against isolates of Gram-negative bacilli harboring AmpC beta-lactamases. Piperacillin-tazobactam has recently been reformulated to include ethylenediaminetetraacetic acid and sodium citrate; this new formulation has been shown to be compatible in vitro with the two aminoglycosides, gentamicin and amikacin, allowing for simultaneous Y-site infusion, but not with tobramycin.

Comparative review of the carbapenems.

The carbapenems are beta-lactam antimicrobial agents with an exceptionally broad spectrum of activity. Older carbapenems, such as imipenem, were often susceptible to degradation by the enzyme dehydropeptidase-1 (DHP-1) located in renal tubules and required co-administration with a DHP-1 inhibitor such as cilastatin. Later additions to the class such as meropenem, ertapenem and doripenem demonstrated increased stability to DHP-1 and are administered without a DHP-1 inhibitor.

Faropenem: review of a new oral penem.

Faropenem medoxomil is a new orally administered penem antibiotic. Its chiral tetrahydrofuran substituent at position C2 is responsible for its improved chemical stability and reduced CNS effects, compared with imipenem. Faropenem demonstrates broad-spectrum in vitro antimicrobial activity against many Gram-positive and -negative aerobes and anaerobes, and is resistant to hydrolysis by nearly all beta-lactamases, including extended-spectrum beta-lactamases and AmpC beta-lactamases.

Genetic relatedness of multidrug-resistant Escherichia coli cultured from geographically diverse outpatient, midstream urine specimens.

Genomic DNA from 70 demographically matched geographically diverse pairs of urinary isolates of antimicrobial-susceptible and multidrug-resistant Escherichia coli was restricted using XbaI and analyzed by pulsed-field gel electrophoresis. Antimicrobial-susceptible isolates demonstrated limited genetic relatedness, whereas 2 epidemiologic clusters containing a total of 40 isolates (57.1%) were identified among the multidrug-resistant isolates.

Multidrug resistance in pediatric urinary tract infections.

Urinary tract infections (UTIs) represent a common infection in the pediatric population. Escherichia coli is the most common uropathogen in children, and antimicrobial resistance in this species complicates the treatment of pediatric UTIs. Despite the impact of resistance on empiric antibiotic choice, there is little data on multidrug resistance in pediatric patients.

Fluoroquinolone-resistant urinary isolates of Escherichia coli from outpatients are frequently multidrug resistant: results from the North American Urinary Tract Infection Collaborative Alliance-Quinolone Resistance study.

Ciprofloxacin-resistant Escherichia coli isolates (n = 1,858) from outpatient midstream urine specimens at 40 North American clinical laboratories in 2004 to 2005 were frequently resistant to ampicillin (79.8% of isolates) and trimethoprim-sulfamethoxazole (66.5%); concurrent resistance to cefdinir (9.

Antibiotic resistance in Escherichia coli outpatient urinary isolates: final results from the North American Urinary Tract Infection Collaborative Alliance (NAUTICA).

The North American Urinary Tract Infection Collaborative Alliance (NAUTICA) study determined the antibiotic susceptibility to commonly used agents for urinary tract infections of outpatient Escherichia coli urinary isolates obtained from various geographic regions in the USA and Canada. NAUTICA involved 40 medical centres (30 from the USA and 10 from Canada). From April 2003 to June 2004 inclusive, each centre submitted up to 50 consecutive outpatient midstream urine isolates.

Tigecycline: a novel glycylcycline antibiotic.

Tigecycline, the first-in-class glycylcycline, was developed to recapture the broad spectrum of activity of the tetracycline class and to treat patients with difficult-to-treat bacterial infections. Tigecycline's in vitro spectrum of activity encompasses aerobic, facultative and anaerobic Gram-positive and -negative bacteria, including antimicrobial-resistant bacteria such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis and Enterococcus faecium, and extended-spectrum beta-lactamase-producing Enterobacteriaceae. Clinical trials involving patients with complicated skin and skin-structure infections and complicated intra-abdominal infections, including patients infected with methicillin-resistant S.

In vitro interactions of anidulafungin with azole antifungals, amphotericin B and 5-fluorocytosine against Candida species.

Anidulafungin, an echinocandin, is in late stage development for the treatment of fungal infections. We investigated the activity of anidulafungin in combination with other antifungal agents (fluconazole, itraconazole, ketoconazole, amphotericin B and 5-fluorocytosine) against four isolates each of Candida albicans, Candida glabrata, Candida parapsilosis and Candida tropicalis, and two isolates of Candida krusei using a macrobroth chequerboard method with interactions evaluated by fractional inhibitory concentration indices (FICIs). Additive activity (FICI > 0.

Antibiotic resistance trends in paediatric uropathogens.

The antimicrobial susceptibility patterns of paediatric uropathogens to six of the most common antibiotics in use for urinary tract infections were determined. The bacterial isolates came from the urine of children presenting as outpatients to participating US hospitals between April 2002 and May 2004. Strains of the six most common uropathogens were included in the analysis.

Stable antimicrobial susceptibility rates for clinical isolates of Pseudomonas aeruginosa from the 2001-2003 tracking resistance in the United States today surveillance studies.

From 2001 to 2003, rates of susceptibility to piperacillin-tazobactam (86%), ceftazidime (80%), ciprofloxacin (68%), and levofloxacin (67%) did not decrease or decreased by <1.5%, whereas the rate of susceptibility to gentamicin decreased by 3.2% (from 75.

Role of efflux mechanisms on fluoroquinolone resistance in Streptococcus pneumoniae and Pseudomonas aeruginosa.

Prokaryotic efflux mechanisms can effectively increase the intrinsic resistance of bacteria by actively transporting antibiotics out of cells, thus reducing the effective concentration of these agents. The fluoroquinolones, similar to most other antimicrobial classes, are susceptible to efflux mechanisms, particularly in Gram-negative organisms, such as Pseudomonas aeruginosa. Resistant P.

Virulence characteristics and phylogenetic background of multidrug-resistant and antimicrobial-susceptible clinical isolates of Escherichia coli from across the United States, 2000-2001.

Background: Increases in antimicrobial resistance in Escherichia coli have been paralleled by an increasing incidence of E. coli sepsis, suggesting a possible link between resistance and virulence.

Methods: All 76 multidrug-resistant (MDR) E.

Emerging resistance among bacterial pathogens in the intensive care unit--a European and North American Surveillance study (2000-2002).

Background: Globally ICUs are encountering emergence and spread of antibiotic-resistant pathogens and for some pathogens there are few therapeutic options available.

Methods: Antibiotic in vitro susceptibility data of predominant ICU pathogens during 2000-2 were analyzed using data from The Surveillance Network (TSN) Databases in Europe (France, Germany and Italy), Canada, and the United States (US).

Results: Oxacillin resistance rates among Staphylococcus aureus isolates ranged from 19.