ABSTRACT
We describe a hospital-based outbreak caused by multidrug-resistant, Klebsiella pneumoniae carbapenemase 3-producing, mcr-1-positive K. pneumoniae sequence type 45 in Portugal. mcr-1 was located in an IncX4 plasmid. Our data highlight the urgent need for systematic surveillance of mcr-1 to support adequate therapeutic choices in the nosocomial setting.
Subject(s)
Bacterial Proteins/genetics , Hospitalization , Klebsiella Infections/epidemiology , Klebsiella Infections/microbiology , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/genetics , beta-Lactamases/genetics , Aged , Aged, 80 and over , Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial , Female , History, 21st Century , Humans , Klebsiella Infections/history , Male , Microbial Sensitivity Tests , Middle Aged , Multilocus Sequence Typing , Portugal/epidemiologyABSTRACT
OBJECTIVES: To assess the proportion of Escherichia coli and Klebsiella pneumoniae from Canadian hospitals that produce extended-spectrum ß-lactamases (ESBLs), AmpC ß-lactamases and carbapenemases, as well as to describe the patterns of antibiotic resistance and molecular characteristics of these organisms. METHODS: Some 5451 E. coli and 1659 K. pneumoniae were collected from 2007 to 2011 inclusive as part of the ongoing CANWARD national surveillance study. Antimicrobial susceptibility testing was performed to detect putative ESBL, AmpC and carbapenemase producers, which were then further characterized by PCR and sequencing to detect resistance genes. In addition, isolates were characterized by PFGE and an allele-specific PCR to detect isolates of sequence type (ST) 131. RESULTS: The proportion of ESBL-producing E. coli (2007, 3.4%; 2011, 7.1%), AmpC-producing E. coli (2007, 0.7%; 2011, 2.9%) and ESBL-producing K. pneumoniae (2007, 1.5%; 2011, 4.0%) among the isolates collected increased during the study period. The majority of ESBL-producing E. coli (>95%), AmpC-producing E. coli (>97%) and ESBL-producing K. pneumoniae (>89%) remained susceptible to colistin, amikacin, ertapenem and meropenem. Isolates were generally unrelated by PFGE (<80% similarity); however, ST131 was identified among 55.8% and 28.7% (P < 0.001) of ESBL- and AmpC-producing E. coli, respectively. CTX-M-15 was the dominant genotype in both ESBL-producing E. coli (66.2%) and ESBL-producing K. pneumoniae (50.0%), while the dominant genotype in AmpC-producing E. coli was CMY-2 (55.7%). Carbapenemase production was identified in 0.04% (n = 2) of E. coli and 0.06% (n = 1) of K. pneumoniae, all of which produced KPC-3. CONCLUSIONS: The proportion of ESBL- and AmpC-producing E. coli and K. pneumoniae increased significantly during the study period, while the number of carbapenemase producers remained low (<1%). Compared with AmpC-producing E. coli, ESBL-producing E. coli were significantly associated with multidrug resistance and the ST131 clone.
Subject(s)
Cross Infection/epidemiology , Escherichia coli Infections/epidemiology , Escherichia coli/genetics , Klebsiella Infections/epidemiology , Klebsiella pneumoniae/genetics , beta-Lactamases/genetics , Adolescent , Adult , Aged , Anti-Bacterial Agents/pharmacology , Bacteria/classification , Bacteria/drug effects , Bacteria/genetics , Bacteria/isolation & purification , Bacterial Infections/epidemiology , Bacterial Infections/microbiology , Bacterial Proteins/genetics , Canada/epidemiology , Child , Cross Infection/history , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli/isolation & purification , Escherichia coli Infections/history , Female , Genotype , History, 21st Century , Humans , Klebsiella Infections/history , Klebsiella pneumoniae/isolation & purification , Male , Microbial Sensitivity Tests , Middle Aged , Molecular Sequence Data , Young Adult , beta-Lactam Resistance/geneticsABSTRACT
Pyogenic liver abscess (PLA) is a common intra-abdominal infection in adults. In this study, we aim to explore demographic and clinical characteristics of PLA focusing on Klebsiella pneumoniae (K. pneumoniae) induced PLA (KP-PLA) in mainland China. A retrospective review of medical records from all patients with KP-PLA admitted to a tertiary teaching hospital over a 21-year period (1994-2015) was performed. Among 296 PLA cases with confirmed culture-positive data, K. pneumoniae was revealed as the predominant pathogen (n = 189, 63.9%), followed by Escherichia coli (n = 39, 13.2%). Strikingly, KP-PLA patients had a higher incidence of metabolic disorders, such as diabetes mellitus (49.7% vs. 36.4%, P = 0.027; odds ratio (OR): 1.725; 95% confidence interval (CI): 1.061-2.805), hypertension (38.1% vs. 19.6%, P = 0.001; OR: 2.520; 95% CI: 1.439-4.413), and fatty liver (32.3% vs. 14.0%, P = 0.001; OR: 2.923; 95% CI: 1.564-5.462) than those with non-K. pneumoniae induced PLA (non-KP-PLA). Moreover, patients with KP-PLA had higher susceptibility to septic metastatic infection at distant sites compared to those with non-KP-PLA (10.6% vs. 3.7%, p = 0.038). Our results indicate that K. pneumoniae is the predominant pathogen of PLA in mainland China. KP-PLA is frequently diagnosed in patients with metabolic diseases and has a higher risk for septic metastatic infection.