Multicenter Evaluation of Ceftazidime-Avibactam Susceptibility Testing of and Pseudomonas aeruginosa on the Vitek 2 System.

In this multisite study, Vitek 2 AST-Gram-Negative Ceftazidime/Avibactam test results for 1,073 isolates (866 and 207 ) were compared to the Clinical and Laboratory Standards Institute (CLSI) broth microdilution (BMD) reference method. The results were analyzed for essential agreement (EA), category agreement (CA), major error rates, and very major error rates following FDA/ISO performance criteria using the FDA-recognized CLSI/EUCAST breakpoints (sensitive [S], ≤8/4 μg/ml; resistant [R], ≥16/4 μg/ml). The overall EA was 94.

Asymptomatic rectal colonization with carbapenem-resistant Enterobacteriaceae and Clostridium difficile among residents of a long-term care facility in New York City.

Background: Residents of long-term care facilities (LTCFs) are at increased risk for colonization and development of infections with multidrug-resistant organisms. This study was undertaken to determine prevalence of asymptomatic rectal colonization with Clostridium difficile (and proportion of 027/NAP1/BI ribotype) or carbapenem-resistant Enterobacteriaceae (CRE) in an LTCF population.

Methods: Active surveillance was performed for C difficile and CRE rectal colonization of 301 residents in a 320-bed (80-bed ventilator unit), hospital-affiliated LTCF with retrospective chart review for patient demographics and potential risk factors.

Evaluation of Remel Spectra CRE Agar for Detection of Carbapenem-Resistant Bacteria from Rectal Swabs Obtained from Residents of a Long-Term-Care Facility.

We compared the Remel Spectra CRE agar plate to CDC standard methodology for the isolation of carbapenem-resistant Enterobacteriaceae (CRE) from 300 rectal swab specimens obtained from patients residing in a long-term-care facility (LTCF). Multiplex PCR experiments were performed on isolates to identify specific Klebsiella pneumoniae carbapenemases (KPC) and additional β-lactamases. Of the 300 patients, 72 (24%) harbored CRE and were PCR positive for KPC enzymes.

Comparison of meropenem MICs and susceptibilities for carbapenemase-producing Klebsiella pneumoniae isolates by various testing methods.

We describe the levels of agreement between broth microdilution, Etest, Vitek 2, Sensititre, and MicroScan methods to accurately define the meropenem MIC and categorical interpretation of susceptibility against carbapenemase-producing Klebsiella pneumoniae (KPC). A total of 46 clinical K. pneumoniae isolates with KPC genotypes, all modified Hodge test and bla(KPC) positive, collected from two hospitals in NY were included.

Susceptibility of gram-negative pathogens isolated from patients with complicated intra-abdominal infections in the United States, 2007-2008: results of the Study for Monitoring Antimicrobial Resistance Trends (SMART).

During 2007-2008, 1,036 gram-negative bacilli were isolated from patients with complicated intra-abdominal infections in the United States. Against members of the family Enterobacteriaceae, the most active agents in vitro were ertapenem, imipenem, and amikacin, while the least active agent was ampicillin-sulbactam. Ertapenem and imipenem were active against all extended-spectrum-beta-lactamase (ESBL)-positive Escherichia coli.

Rhizomucor variabilis var. regularior and Hormographiella aspergillata infections in a leukemic bone marrow transplant recipient with refractory neutropenia.

Rhizomucor variabilis and Hormographiella aspergillata rarely cause human infections. This report details a fatal case of a 14-year-old female with leukemia posthematopoietic cell transplant and relapse with refractory pancytopenia. The patient first developed an R.

Accuracies of beta-lactam susceptibility test results for Pseudomonas aeruginosa with four automated systems (BD Phoenix, MicroScan WalkAway, Vitek, and Vitek 2).

Contemporary clinical isolates and challenge strains of Pseudomonas aeruginosa were tested by four automated susceptibility testing systems (BD Phoenix, MicroScan WalkAway, Vitek, and Vitek 2; two laboratories with each) against six broad-spectrum beta-lactams, and the results were compared to reference broth microdilution (BMD) and to consensus results from three validated methods (BMD, Etest [AB Biodisk, Solna, Sweden], and disk diffusion). Unacceptable levels of error (minor, major, and very major) were detected, some with systematic biases toward false susceptibility (piperacillin-tazobactam and imipenem) and others toward false resistance (aztreonam, cefepime, and ceftazidime). We encourage corrective action by the system manufacturers to address test biases, and we suggest that clinical laboratories using automated systems should consider accurate alternative methods for routine use.

Use of cefepime for the treatment of infections caused by extended spectrum beta-lactamase-producing Klebsiella pneumoniae and Escherichia coli.

An investigation to determine the efficacy of cefepime in treating infections caused by extended spectrum beta-lactamase (ESBL)-producing strains of Klebsiella pneumonia and Escherichia coli was performed. Retrospective chart reviews were conducted on patients who received cefepime and had an ESBL-producing E. coli or K.

Lactobacillus acidophilus bacteraemia after use of a probiotic in a patient with AIDS and Hodgkin's disease.

We report the case of a patient who developed bacteraemia and septic pulmonary emboli with Lactobacillus acidophilus after taking a probiotic containing this organism.

Mycobacterium thermoresistibile infection following knee-replacement surgery.

We report a case of Mycobacterium thermoresistibile as a cause of infection following total knee replacement. This infection was masked by the prior isolation of a vancomycin-resistant enterococcus. The infection was resolved with long-term therapy using moxifloxacin and doxycycline.

Comparison of the ESP and BACTEC systems for testing susceptibilities of Mycobacterium tuberculosis complex isolates to pyrazinamide.

Fifty isolates of Mycobacterium tuberculosis complex were tested for susceptibility to pyrazinamide (PZA) by the ESP (Trek Diagnostic Systems, Westlake, Ohio) and BACTEC (BD Biosciences, Sparks, Md.) test systems. Initial results showed concordance for 48 of the isolates.

Pseudo-outbreak of Mycobacterium fortuitum due to contaminated ice machines.

Background: An almost 4-fold increase from normal baseline levels in the isolation of Mycobacterium fortuitum from respiratory tract specimens was observed. The majority of these isolates were obtained from patients residing on 1 of 2 wards, prompting an epidemiologic investigation.

Methods: In addition to patient specimens, environmental cultures were collected from various water sources on the 2 affected wards.