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Background To identify the clinical characteristics and risk factors for mortality of patients with cefepime-resistant Pseudomonas aeruginosa (FRPa) bacteremia. Methods This retrospective study analyzed adult patients with FRPa bacteremia hospitalized between January 2006 and December 2011. Results Seventy eight patients (46 male, 32 female; mean age: 72.2 ± 14.1 years) were included. Of them, 46 (59.0%) had ventilator use and 45 (57.7%) had intensive care unit stay. All the bacteremia episodes were health-care associated or hospital acquired, and 55.1% of FRPa blood isolates were multidrug resistant. The sources of bacteremia were identified in 42 patients (53.8%), with pneumonia being the most common one (28/42; 66.7%). The mean interval between admission and the sample date of the first FRPa-positive blood culture was 45.8 ± 52.6 days. The mean Pittsburgh bacteremia score was 5.0 ± 3.4. The 15-day and 30-day mortality rates were 50.0% and 65.4%, respectively. Patients (41; 52.6%) on appropriate antibiotic therapy within 72 hours of the first FRPa-positive blood culture had a higher 30-day survival rate than those without (48.8% vs. 18.9%, p = 0.011 by log-rank test). Multivariate analyses revealed that a higher Pittsburgh bacteremia score was an independent risk factor for either 15-day ( p = 0.002) or 30-day mortality ( p = 0.010), and appropriate antibiotic therapy within 72 hours was an independent protecting factor for either 15-day ( p = 0.049) or 30-day mortality ( p = 0.017). Conclusion FRPa bacteremia had a high mortality rate. The disease severity and appropriate antimicrobial therapy within 72 hours of positive blood culture were related to the patients' outcome.

Nosocomial infections caused by multidrug-resistant (MDR) Acinetobacter baumannii have been increasing in recent years, posing a threat to public health worldwide. The susceptibility to eight antimicrobial agents of 35 clinical A. baumannii isolates from Taiwan was tested. Isolates were examined by polymerase chain reaction (PCR) and sequencing for β-lactamase genes and mutations in the gyrA and parC genes. Expression of AdeB, an efflux pump protein, was evaluated by real-time quantitative PCR. The level of adeB expression correlated with resistance to ciprofloxacin and ampicillin/sulbactam in A. baumannii isolates. Almost all isolates with full resistance to ciprofloxacin had both high adeB expression and point mutations in parC and gyrA , but 4 intermediate-resistant isolates had only high adeB expression without point mutations in gyrA or parC , in contrast to 18 susceptible isolates with low adeB expression and without mutations in gyrA or parC . Sixteen isolates (45.7%) carrying a type 1 integron were MDR as well as being more resistant to imipenem, amikacin, gentamicin, ceftazidime or cefepime than those without the integron. The class 1 integron in A. baumannii carried different resistance gene cassettes, including 5′CS- bla IMP-1 – aadA4 –3′CS, 5′CS– aacA4 – aadA1 –3′CS and 5′CS– aacC1 – aadA1 –3′CS. In conclusion, expression of the adeB gene was associated with resistance to ciprofloxacin and ampicillin/sulbactam in A. baumannii . Multiple mutations in gyrA and parC also played a role in ciprofloxacin resistance. The major metallo-β-lactamase contributing to imipenem resistance in A. baumannii in Taiwan was bla IMP-1 , which was carried by the class 1 integron. The class 1 integron was associated with the MDR phenotype in A. baumannii .

Chronic sclerosing osteomyelitis caused by Chryseobacterium meningosepticum was observed in a woman with steroid use. Her chronic sclerosing osteomyelitis was cured with ciprofloxacin. English literature review found 4 cases of bone-joint infection due to C. meningosepticum. The implications of treatment with a fluoroquinolone were discussed.

Forty-six cephamycin-resistant Escherichia coli isolates from patients diagnosed with community-acquired urinary tract infection were selected in order to study their resistance mechanism. With the exception of one isolate producing CMY-4, all isolates produced a CMY-2 β-lactamase. Molecular typing showed that the CMY-2-producing isolates were not related. Cephamycin resistance was plasmid encoded and conjugatively transferred. Plasmid digest profiles suggested that the plasmids were different. Thirty-nine of the 45 CMY-2-producing isolates harboured a plasmid containing a specific DNA fragment, IS Ecp1 – bla CMY-2 – blc – sugE , which was identical to those previously published in CMY-2-producing Salmonella enterica serotype Choleraesuis (SCB67) and Salmonella enterica serotype Typhimurium (pNF1358) from Taiwan and the USA, respectively. Among the remaining six isolates, insertion of IS 1294 and IS 1 at different positions was observed in one and five isolates, respectively. The regions surrounding bla CMY-2 of the six isolates were identical to the other 39 isolates as well as to SCB67 and pNF1358. Since the present identical transmissible bla CMY-2 -carrying element was observed in food animal sources both in the USA and Taiwan, its possible transmission to humans, as revealed in this study, is of great concern. Awareness of this mobile resistance element is required to prevent introduction into hospitals and to reduce the spread of this emerging resistance within the community.

Background: Cell-free DNA is detectable in circulating blood. Numerous reports in the literature have pointed out that cell-free DNA in plasma or serum has the clinical potential to be a more specific tumor marker for the diagnosis and prognosis, as well as the early detection, of cancer. Methods: In order to adapt cell-free DNA to a routine clinical laboratory test, we used commercial kits such as the QIAamp blood kit for DNA extraction and the PicoGreen DNA kit for DNA quantification. This was done so our results and the normal reference value established would allow to be compared by other laboratories. We have established the normal reference level of cell-free DNA for females and males from age 20–70 years. We also detected elevated cell-free DNA in all cancers that were tested in this study, including carcinomas, leukemia and lymphoma. Results: Our study indicates that the elevation of serum cell-free DNA was usually detected in specimens containing elevated tumor markers and is most likely associated with tumor metastases. The electrophoretic pattern of cell-free DNA showed that cell-free DNA from cancer patient is fragmented, containing smaller DNA (100 bp) not found in normal cell-free DNA. Conclusions: Measuring cell-free DNA may complement currently used tumor markers for the management of cancer patients.