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This study was conducted to investigate the clinical significance, manifestations, microbiological characteristics and outcomes of carbapenem-resistant Enterobacteriaceae (CRE) isolates, and compare the clinical features of community- and healthcare-acquired CRE isolates. A total of 78 patients were identified to have CRE. Klebsiella pneumoniae was the most common pathogens (n = 42, 53.8%), followed by Enterobacter cloacae (n = 24, 30.8%), and Escherichia coli (n = 11, 14.1%). Most of the patients acquired CRE from healthcare settings (n = 55, 70.5%), and other cases got CRE from community settings (n = 23, 29.5%). Nine cases (11.5%) were classified as CRE colonization. Among the remaining 69 cases of CRE infections, pneumonia (n = 28, 40.6%) was the most common type of infections, followed by urinary tract infection (n = 24, 34.8%), and intra-abdominal infection (n = 16, 23.2%). The patients acquired CRE from community settings were more likely to be elderly, female, and had more urinary tract infections than from healthcare settings. In contrast, the patients acquired CRE from healthcare settings had more intra-abdominal infections, intra-abdominal surgery, and presence of indwelling device than from community settings. In conclusion, community-acquired CRE are not rare, and their associated clinical presentations are different from healthcare-acquired CRE.

Longitudinal nationwide surveillance data on antimicrobial non-susceptibility and prevalence of extended-spectrum β-lactamases (ESBLs) as well as AmpC β-lactamases producers among Escherichia coli from different sources in the community settings are limited. Such data may impact treatment practice. The present study investigated E. coli from outpatients and patients visiting emergency rooms collected by the Taiwan Surveillance of Antimicrobial Resistance (TSAR) program. A total of 3481 E. coli isolates were studied, including 2153 (61.9%) from urine and 1125 (32.3%) from blood samples. These isolates were collected biennially between 2002 and 2012 from a total of 28 hospitals located in different geographic regions of Taiwan. Minimum inhibitory concentrations (MIC) were determined using methods recommended by the Clinical Laboratory Standards Institute (CLSI). The prevalence and factors associated with the presence of ESBL and AmpC β-lactamase-producers were determined. Significant increases in non-susceptibility to most β-lactams and ciprofloxacin occurred during the study period. By 2012, non-susceptibility to cefotaxime and ciprofloxacin reached 21.1% and 26.9%, respectively. The prevalence of ESBL- and AmpC- producers also increased from 4.0% and 5.3%, respectively, in 2002–2004, to 10.7% for both in 2010–2012 (P < 0.001). The predominant ESBL and AmpC β-lactamase genes were CTX-M and CMY-types, respectively. Non-susceptibility of urine isolates to nitrofurantoin remained at around 8% and to fosfomycin was low (0.7%) but to cefazolin (based on the 2014 CLSI urine criteria) increased from 11.5% in 2002–2004 to 23.9% in 2010–2012 (P

Background This study was conducted to investigate an outbreak caused by imipenem-resistant Acinetobacter baumannii (IRAB) in a medical intensive care unit (ICU) in a regional hospital. Methods In response to an IRAB outbreak from October 2012 to February 2013, we developed several infection control measures, including an extensive review process of environmental cleaning and disinfection, and used molecular methods to identify each clinical and environmental IRAB isolate. Results During this five-month period, 22 patients were colonized with IRAB and 18 patients had IRAB infections. The in-hospital mortality rate was significantly higher among patients with infections rather than colonizations (44.4% vs 9.1%, p = 0.028). Additionally, nine environmental specimens, including five specimens collected after terminal disinfection, were positive for IRAB. 12 environmental isolates and 28 of 36 available clinical isolates belonged to one unique pulsotype A, which was confirmed by molecular methods. We found the concentration of disinfectant, 0.08% sodium hypochlorite, was inadequate. After correcting the environmental cleansing methods, the surveillance study showed no further IRAB isolates on the control panel surfaces of the medical equipment or in patients in the ICU. Additionally, an in vitro study of IRAB immersed in different concentrations of sodium hypochlorite showed that 0.5% sodium hypochlorite eradicates IRAB after 30 seconds of inoculation, but 0.08% sodium hypochlorite only reduces the bacterial load. Conclusions This study highlights the importance of the preparation of disinfectants to adequately achieve environmental disinfection in the control of IRAB outbreaks in the ICU.

OBJECTIVES: The global spread and increasing incidence of carbapenem non-susceptible Klebsiella pneumoniae (CnSKP) has made its treatment difficult, increasing the mortality. To establish nationwide data on CnSKP spread and carbapenem-resistance mechanisms, we conducted a national surveillance study in Taiwanese hospitals. METHODS: We collected 100 and 247 CnSKP isolates in 2010 and 2012, respectively. The tests performed included antibiotic susceptibility tests; detection of carbapenemase, extended-spectrum β-lactamases (ESBL), and AmpC β-lactamases genes; outer membrane porin profiles; and genetic relationship with pulsed-field gel electrophoresis and multilocus sequence type. RESULTS: The resistance rate of CnSKP isolates to cefazolin, cefotaxime, cefoxitin, ceftazidime, and ciprofloxacin was over 90%. Susceptibility rate to tigecycline and colistin in 2010 was 91.0% and 83.0%, respectively; in 2012, it was 91.9% and 87.9%, respectively. In 2010, carbapenemase genes were detected in only 6.0% of isolates (4 bla IMP-8 and 2 bla VIM-1). In 2012, carbapenemase genes were detected in 22.3% of isolates (41 bla KPC-2, 7 bla VIM-1, 6 bla IMP-8, and 1 bla NDM-1). More than 95% of isolates exhibited either OmpK35 or OmpK36 porin loss or both. Impermeability due to porin mutation coupled with AmpC β-lactamases or ESBLs were major carbapenem-resistance mechanisms. Among 41 KPC-2-producing K. pneumoniae isolates, all were ST11 with 1 major pulsotype. CONCLUSIONS: In 2010 and 2012, the major mechanisms of CnSKP in Taiwan were the concomitance of AmpC with OmpK35/36 loss. KPC-2-KP dissemination with the same ST11 were observed in 2012. The emergence and rapid spread of KPC-2-KP is becoming an endemic problem in Taiwan. The identification of NDM-1 K. pneumoniae case is alarming.

Background The objective of this study was to compare virulence among different Aeromonas species causing bloodstream infections. Methodology/Principal Findings Nine of four species of Aeromonas blood isolates, including A. dhakensis, A. hydrophila, A. veronii and A. caviae were randomly selected for analysis. The species was identified by the DNA sequence matching of rpoD. Clinically, the patients with A. dhakensis bacteremia had a higher sepsis-related mortality rate than those with other species (37.5% vs. 0%, P = 0.028). Virulence of different Aeromonas species were tested in C. elegans, mouse fibroblast C2C12 cell line and BALB/c mice models. C. elegans fed with A. dhakensis and A. caviae had the lowest and highest survival rates compared with other species, respectively (all P values