inosinic-acid and Enterobacteriaceae-Infections

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactam Resistance; beta-Lactamases; beta-Lactams; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Inosine Monophosphate; Microbial Sensitivity Tests

BD Phoenix™ is an automated bacterial identification and susceptibility testing system. Here, its performance in screening IMP-producing Enterobacteriaceae was evaluated. The system identified 97.8% of IMP producers as being nonsusceptible to imipenem or meropenem, which was higher than that identified by the broth microdilution method (91.3%, imipenem; 41.3%, meropenem).

Topics: Anti-Bacterial Agents; Automation, Laboratory; Bacterial Proteins; Carbapenems; DNA, Bacterial; Enterobacter cloacae; Enterobacteriaceae Infections; Imipenem; Inosine Monophosphate; Klebsiella pneumoniae; Meropenem; Microbial Sensitivity Tests

The prevalence of carbapenem-resistant Enterobacteriaceae (CRE) has been increasing at medical institutions in Japan without even noticing. Recently, we performed a point prevalence survey for CRE carriage at a medical facility in northern Osaka that demonstrated an unexpectedly high prevalence of bla

Topics: Aged, 80 and over; Bacterial Proteins; beta-Lactamases; Carbapenem-Resistant Enterobacteriaceae; Carbapenems; Carrier State; Cross Infection; Enterobacteriaceae Infections; Feces; Female; Follow-Up Studies; Hospitals; Humans; Inosine Monophosphate; Japan; Long-Term Care; Male; Prevalence; Risk Factors

The MALDI Biotyper Selective Testing of Antibiotic Resistance-β-Lactamase (MBT STAR-BL) assay enables rapid detection of β-lactamase activity using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. The assay is based on analysis of bacterially induced hydrolysis of β-lactam antibiotics. We investigated the performance of the MBT STAR-BL assay for detecting IMP metallo-β-lactamase (MBL) activity in Enterobacteriaceae. A total of 145 strains (30 Escherichia coli, 43 Klebsiella pneumoniae, and 72 Enterobacter cloacae complex) were evaluated using meropenem hydrolysis assays. The MBT STAR-BL correctly identified all 48 IMP MBL producers as positive, even those exhibiting a low minimal inhibitory concentration (MIC) (1 μg/mL) for meropenem. Conversely, all non-IMP MBL producers, including strains with higher MICs (4 or 8 μg/mL), were correctly identified as negative. The MBT STAR-BL is a rapid, accurate, and reliable system for detecting IMP MBL activity in Enterobacteriaceae.

Topics: beta-Lactam Resistance; beta-Lactamases; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Inosine Monophosphate; Microbial Sensitivity Tests; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

IMP and VIM carbapenemases, in association with class 1 integrons, have spread globally among multiple Enterobacteriaceae species. We characterized IMP- and VIM-encoding transferable plasmids of clinical Enterobacteriaceae collected from two global surveillance programmes.. We performed conjugation and transformation experiments for 38 IMP and 89 VIM producers. Plasmids, obtained from transconjugants or transformants, were sequenced with Illumina next-generation sequencing and analysed for replicon types and antimicrobial resistance genes.. A total of 41 transconjugants (blaIMP, n = 22; blaVIM, n = 19) and 10 transformants (blaIMP, n = 1; blaVIM, n = 9) were obtained. Broad-host-range IncL/M, IncC and IncN plasmids were associated with blaIMP and blaVIM, contained various integrons and showed inter-species and international distribution. Narrow-host-range IncFII(K) plasmids were limited to Klebsiella pneumoniae with blaIMP-26 from the Philippines, while IncR and IncHI1B-IncFIB(Mar) plasmids were restricted to K. pneumoniae with blaVIM from Greece and Spain. IncA-like hybrid plasmids were detected in Enterobacter xiangfangensis from Italy and K. pneumoniae from Spain. Transferable plasmids were major contributors of antimicrobial resistance genes among Enterobacteriaceae with blaIMP and blaVIM.. This is the first report, to the best of our knowledge, describing blaIMP on IncFII(K) plasmids and blaVIM on IncL/M, IncN2, IncHI1B-IncFIB(Mar) and IncX3-IncC-like plasmids and showed that broad-host-range and narrow-host-range plasmids have contributed to the global spread of blaIMP and blaVIM among different species. This study highlights the importance of molecular analysis of plasmids in providing insight into horizontal spread of these carbapenemases.

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Enterobacteriaceae; Enterobacteriaceae Infections; Epidemiological Monitoring; Genome, Bacterial; Genomics; Greece; High-Throughput Nucleotide Sequencing; Humans; Inosine Monophosphate; Integrons; Italy; Microbial Sensitivity Tests; Plasmids; Spain

Identification of carbapenemase-producing Enterobacteriaceae (CPE) in faecal specimens is challenging. This fact is particularly critical because low-level carbapenem-resistant organisms such as IMP-producing CPE are most prevalent in Japan. We developed a modified selective medium more suitable for IMP-type CPE.. Fifteen reference CPE strains producing different types of β-lactamases were used to evaluate the commercially available CHROMagar KPC and chromID CARBA as well as the newly prepared MC-ECC medium (CHROMagar ECC supplemented with meropenem, cloxacillin, and ZnSO. All tested strains producing NDM-, KPC-, and OXA-48-carbapenemases were successfully cultured in the media employed. Although most of the IMP-positive strains did not grow in CHROMagar KPC, chromID CARBA, or MC-ECC, all tested strains grew on M-ECC. When faecal samples were applied to the media, M-ECC medium allowed the best growth of IMP-type CPE with a significantly higher sensitivity (99.3%) than that of chromID CARBA (13.9%).. M-ECC medium was determined as the most favourable selective medium for the detection of IMP-type CPE as well as other types of CPE.

Topics: Bacterial Proteins; Bacterial Typing Techniques; beta-Lactamases; Culture Media; Enterobacteriaceae; Enterobacteriaceae Infections; Feces; Humans; Inosine Monophosphate

IMP-type metallo-β-lactamase enzymes have been reported in different geographical areas and in various Gram-negative bacteria. However, the risk factors and epidemiology pertaining to IMP-type metallo-β-lactamase-producing Enterobacter cloacae (IMP-producing E. cloacae) have not been systematically evaluated. We conducted a retrospective, matched case-control study of patients from whom IMP-producing E. cloacae isolates were obtained, in addition to performing thorough molecular analyses of the clinically obtained IMP-producing E. cloacae isolates. Unique cases with IMP-producing E. cloacae isolation were included. Patients with IMP-producing E. cloacae were matched to uninfected controls at a ratio of 1 to 3. Fifteen IMP-producing E. cloacae cases were identified, with five of the isolates being obtained from blood, and they were matched to 45 uninfected controls. All (100%) patients from whom IMP-producing E. cloacae isolates were obtained had indwelling devices at the time of isolation, compared with one (2.2%) uninfected control. Independent predictors for isolation of IMP-producing E. cloacae were identified as cephalosporin exposure and invasive procedures within 3 months. Although in-hospital mortality rates were similar between cases and controls (14.3% versus 13.3%), the in-hospital mortality of patients with IMP-producing E. cloacae-caused bacteremia was significantly higher (40%) than the rate in controls. IMP-producing E. cloacae isolates were frequently positive for other resistance determinants. The MICs of meropenem and imipenem were not elevated; 10 (67%) and 12 (80%) of the 15 IMP-producing E. cloacae isolates had a MIC of ≤ 1 μg/ml. A phylogenetic tree showed a close relationship among the IMP-producing E. cloacae samples. Indwelling devices, exposure to cephalosporin, and a history of invasive procedures were associated with isolation of IMP-producing E. cloacae. Screening for carbapenemase production is important in order to apply appropriate clinical management and infection control measures.

Topics: Aged; Aged, 80 and over; Bacteremia; Bacterial Proteins; beta-Lactamases; Cephalosporins; Enterobacter cloacae; Enterobacteriaceae Infections; Female; Hospital Mortality; Humans; Imipenem; Infection Control; Inosine Monophosphate; Japan; Male; Meropenem; Middle Aged; Phylogeny; R Factors; Retrospective Studies; Risk Factors; Tertiary Healthcare; Thienamycins