We investigated the mechanism of imipenem resistance in Enterobacter aerogenes strain 810, a clinical isolate from the United States for which the imipenem MIC was 16 micro g/ml and the meropenem MIC was 8 micro g/ml. An imipenem-susceptible revertant, strain 810-REV, was obtained after multiple passages of the strain on nonselective media. For the revertant, the imipenem MIC was </=1 micro g/m...

introduction: drug utilization evaluation (due) studies are designed to assess drug usage appropriateness. dues have traditionally focused on drugs with high price tags, complicated dosage schedules, narrow therapeutic indices and regular side effects. the primary goal of the present study is to evaluate imipenem usage in bone marrow transplantation (bmt) wards. methods: the study was a prospec...

A 76-year-old woman had recurrent urosepsis due to extended-spectrum beta -lactamase-positive Escherichia coli. Imipenem resistance was detected after long-term imipenem-meropenem therapy. The carbapenem-hydrolyzing enzyme gene was identified as blaKPC-3. To our knowledge, this is the first documented case in which carbapenem-resistant E. coli emerged during therapy with imipenem and meropenem,...

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...