Pan-drug-resistant (PDR)Acinetobacter baumannii is an important nosocomial pathogen that poses therapeutic challenges. Tigecycline alone or in combination with agents such as colestimethate, imipenem, and/or amikacin is being used clinically to treat PDR A. baumannii infections. The purpose of this study was to compare in vitro susceptibility testing by epsilometric (Etest) methods and the checkerboard (CB) method with testing by time-kill analysis. PDR A. baumannii clinical strains representing eight unique pulsed-field gel electrophoresis clones selected from a total of 32 isolates were tested in vitro with tigecycline, colestimethate, imipenem, and amikacin in single-and two-drug combinations by using two different methods of Etest (with a fixed ratio method [method 1] and with the incorporation of the active drug in medium [method 2]) and by using CB. The three-drug combination of imipenem, tigecycline, and amikacin was also tested by CB. These results were compared to time-kill results. Synergy was consistently detected with the imipenem plus colestimethate and tigecycline plus imipenem combinations. The Etest method with active drug incorporated into the agar allowed us to detect synergy even in the presence of the active drug and was more comparable to CB and time-kill tests. Synergy was detected with the three-drug combination of imipenem, tigecycline, and amikacin by both CB and time-kill methods among several tested clones. These findings indicate the utility of synergy testing to predict activity of specific antibiotic combinations against PDR A. baumannii.In recent years Acinetobacter baumannii, an aerobic, Gramnegative coccobacillus, has emerged as an important nosocomial pathogen due to multiple drug resistance mechanisms, and it can be an extremely difficult microorganism for the clinician to treat (3,8,20,22). It causes a variety of infections that include pneumonia, wound, urinary tract, bloodstream, and intra-abdominal infections (3,8). We had experienced an increased number of cases of A. baumannii with resistant or intermediate susceptibility patterns to carbapenems over a 2-year time frame at our medical center. Growing numbers of isolates locally, nationally, and internationally have shown resistance to antibiotics such as the carbapenems, which previously had excellent activity in vitro and clinically. Our annual medical center antibiograms and a review of the literature (1,9,10,12,20,22,23,25,26) support this. Nontraditional agents, such as colestimethate (polymyxin E) and polymyxin B, despite the associated high toxicities, are being used to treat patients infected with pan-drug-resistant (PDR) A. baumannii (with pan-drug resistance defined as resistance to all routinely tested antimicrobials including carbapenems). Antibiotic resistance has also developed among some strains during treatment with these agents (10,20). Drug treatment with newer antimicrobials or antimicrobial combinations has become increasingly important to eradicate these infections.Tigecycline was approved by the Food ...

Background We describe a successful interdisciplinary liaison program that effectively reduced health care-acquired (HCA), methicillin-resistant Staphylococcus aureus (MRSA) in a university hospital setting. Methods Baseline was from January 2006 to March 2008, and intervention period was April 2008 to September 2009. Staff nurses were trained to be liaisons (link nurses) to infection prevention (IP) personnel with clearly defined goals assigned and with ongoing monthly education. HCA-MRSA incidence per 1,000 patient-days (PD) was compared between baseline and intervention period along with total and non-HCA-MRSA, HCA and non-HCA-MRSA bacteremia, and hand soap/sanitizer usage. Hand hygiene compliance was assessed. Results A reduction in MRSA rates was as follows in intervention period compared with baseline: HCA-MRSA decreased by 28% from 0.92 to 0.67 cases per 1,000 PD (incidence rate ratio, 0.72; 95% confidence interval: 0.62–0.83, P < .001), and HCA-MRSA bacteremia rate was reduced by 41% from 0.18 to 0.10 per 1,000 PD (incidence rate ratio, 0.59; 95% confidence interval: 0.42–0.84, P = .003). Total MRSA rate and MRSA bacteremia rate also showed significant reduction with nonsignificant reductions in overall non-HCA-MRSA and non-HCA-MRSA bacteremia. Hand soap/sanitizer usage and compliance with hand hygiene also increased significantly during IP. Conclusion Link nurse program effectively reduced HCA-MRSA. Goal-defined metrics with ongoing reeducation for the nurses by IP personnel helped drive these results.

IntroductionWe set a goal to reduce the incidence rate of catheter-related bloodstream infections to rate of <1 per 1,000 central line days in a two-year period.MethodsThis is an observational cohort study with historical controls in a 25-bed intensive care unit at a tertiary academic hospital. All patients admitted to the unit from January 2008 to December 2011 (31,931 patient days) were included. A multidisciplinary team consisting of hospital epidemiologist/infectious diseases physician, infection preventionist, unit physician and nursing leadership was convened. Interventions included: central line insertion checklist, demonstration of competencies for line maintenance and access, daily line necessity checklist, and quality rounds by nursing leadership, heightened staff accountability, follow-up surveillance by epidemiology with timely unit feedback and case reviews, and identification of noncompliance with evidence-based guidelines. Molecular epidemiologic investigation of a cluster of vancomycin-resistant Enterococcus faecium (VRE) was undertaken resulting in staff education for proper acquisition of blood cultures, environmental decontamination and daily chlorhexidine gluconate (CHG) bathing for patients.ResultsCenter for Disease Control/National Health Safety Network (CDC/NHSN) definition was used to measure central line-associated bloodstream infection (CLA-BSI) rates during the following time periods: baseline (January 2008 to December 2009), intervention year (IY) 1 (January to December 2010), and IY 2 (January to December 2011). Infection rates were as follows: baseline: 2.65 infections per 1,000 catheter days; IY1: 1.97 per 1,000 catheter days; the incidence rate ratio (IRR) was 0.74 (95% CI = 0.37 to 1.65, P = 0.398); residual seven CLA-BSIs during IY1 were VRE faecium blood cultures positive from central line alone in the setting of findings explicable by noninfectious conditions. Following staff education, environmental decontamination and CHG bathing (IY2): 0.53 per 1,000 catheter days; the IRR was 0.20 (95% CI = 0.06 to 0.65, P = 0.008) with 80% reduction compared to the baseline. Over the two-year intervention period, the overall rate decreased by 53% to 1.24 per 1,000 catheter-days (IRR of 0.47 (95% CI = 0.25 to 0.88, P = 0.019) with zero CLA-BSI for a total of 15 months.ConclusionsResidual CLA-BSIs, despite strict adherence to central line bundle, may be related to blood culture contamination categorized as CLA-BSIs per CDC/NHSN definition. Efforts to reduce residual CLA-BSIs require a strategic multidisciplinary team approach focused on epidemiologic investigations of practitioner- or unit-specific etiologies.

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