In vitro evolution was used to predict whether the IMP-1 metallo-lactamase has the potential to evolve an increased ability to confer resistance to imipenem. Screening of eight libraries containing 9.8 10 1.4 10 (mean standard error) variants per library, with an average of 1.2 mutations per variant, detected no increased resistance to imipenem. The results predict, with >99.9% confidence, that...

In a retrospective 10-year analysis of 3,536 patient-unique isolates, Acinetobacter baumannii imipenem susceptibility declined from 98.1 (1990) to 64.1% (2000), and ciprofloxacin susceptibility decreased from 50.5 to 13.1%. Imipenem median zone diameters decreased from 27. 7 (1997) to 18.8 mm (2000). No outbreaks were detected. Two clusters were identified for 41 strains genotyped by pulsed-fie...

This study compared the in vitro activities of the new long-half-life carbapenem ertapenem (also known as MK-0826 and L-749,345) with those of imipenem, amoxicillin-clavulanate, and ciprofloxacin against 5,558 recent clinical isolates from 11 North American medical centers. We confirmed the greater activity of ertapenem than of imipenem against the Enterobacteriaceae and the greater activity of...

To compare the antipseudomonal efficacy of doripenem and imipenem as well as their abilities to restrict the enrichment of resistant Pseudomonas aeruginosa, multiple-dosing regimens of each drug were simulated at comparable values of the cumulative percentages of a 24-h period that the drug concentration exceeds the MIC under steady-state pharmacokinetic conditions (T(>MIC)) and ratios of the 2...

PURPOSE The antimicrobial activity of doripenem in comparison of imipenem, meropenem and ertapenem among Pseudomonas aeruginosa isolated from burn and Cystic Fibrosis (CF) patients were determined. METHODS Metallo-β-lactamase (MBL) genes in imipenem non susceptible P. aeruginosa isolates were detected using PCR method. The in vitro susceptibilities of doripenem, imipenem, meropenem and ertape...

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 che...

BACKGROUND AND OBJECTIVES Carbapenem resistant Pseudomonas aeruginosa is a serious cause of nosocomial infections. The main purpose of the study is to determine the prevalence rate of imipenem resistant Pseudomonas aeruginosa carrying metallo-ß-lactamase (MBL) genes. MATERIAL AND METHODS 236 Pseudomonas aeruginosa isolates were collected from teaching hospitals of Ahvaz University of Medical ...

Only limited data exist on Pseudomonas aeruginosa ventilator-associated pneumonia (VAP) treated with imipenem, meropenem, or doripenem. Therefore, we conducted a prospective observational study in 169 patients who developed Pseudomonas aeruginosa VAP. Imipenem, meropenem, and doripenem MICs for Pseudomonas aeruginosa isolates were determined using Etests and compared according to the carbapenem...

The lungs of cystic fibrosis (CF) patients are commonly colonized with Pseudomonas aeruginosa biofilms. Chronic endobronchial P. aeruginosa infections are impossible to eradicate with antibiotics, but intensive suppressive antibiotic therapy is essential to maintain the lung function of CF patients. The treatment often includes beta-lactam antibiotics. How these antibiotics influence gene expre...

PURPOSE Combination antibiotic treatment is preferred in nosocomial infections caused by Pseudomonas aeruginosa (P. aeruginosa). In vitro synergism tests were used to choose the combinations which might be used in clinic. The aim of this study was to investigate the synergistic efficacy of synergistic antibiotic combinations in multidrug resistant P. aeruginosa strains. MATERIALS AND METHODS ...