Tun-Chieh Chen

Fluoroquinolones are associated with delayed treatment and resistance in tuberculosis: a systematic review and meta-analysis

BACKGROUND Current guidelines for treating community-acquired pneumonia recommend the use of fluoroquinolones for high-risk patients. Previous studies have reported controversial results as to whether fluoroquinolones are associated with delayed diagnosis and treatment of pulmonary tuberculosis (TB) and the development of fluoroquinolone-resistant Mycobacterium tuberculosis. We performed a systematic review and meta-analysis to clarify these issues. METHODS The following databases were searched through September 30, 2010: PubMed, EMBASE, CINAHL, Cochrane Library, Web of Science, BIOSIS Previews, and the ACP Journal Club. We considered studies that addressed the issues of delay in diagnosis and treatment of TB and the development of resistance. RESULTS Nine eligible studies (four for delays and five for resistance issues) were included in the meta-analysis from the 770 articles originally identified in the database search. The mean duration of delayed diagnosis and treatment of pulmonary TB in the fluoroquinolone prescription group was 19.03 days, significantly longer than that in the non-fluoroquinolone group (95% confidence interval (CI) 10.87 to 27.18, p<0.001). The pooled odds ratio of developing a fluoroquinolone-resistant M. tuberculosis strain was 2.70 (95% CI 1.30 to 5.60, p=0.008). No significant heterogeneity was found among studies in the meta-analysis. CONCLUSIONS Empirical fluoroquinolone prescriptions for pneumonia are associated with longer delays in diagnosis and treatment of pulmonary TB and a higher risk of developing fluoroquinolone-resistant M. tuberculosis.

Proteus mirabilis urinary tract infection and bacteremia: Risk factors, clinical presentation, and outcomes

BACKGROUND/PURPOSE Proteus mirabilis is a common pathogen responsible for complicated urinary tract infections (UTIs) that sometimes causes bacteremia. Most cases of P. mirabilis bacteremia originate from a UTI; however, the risk factors for bacteremia and mortality rates from P. mirabilis UTI have not been determined. METHODS A retrospective, case-control study was performed between May 2008 and November 2010 to identify the risk factors and markers for P. mirabilis bacteremic UTI. Each subject in the case group (all patients were diagnosed with P. mirabilis bacteremia from a urinary tract source) was matched by age and gender to two subjects in the control group (patients diagnosed with P. mirabilis UTI but with negative blood culture results). Clinical presentation and laboratory data were analyzed to determine the risk factors and markers of P. mirabilis bacteremic UTI. RESULTS Sixty-seven bacteremic UTIs and 124 nonbacteremic UTIs were included in this study. Community-acquired infection (p=0.017), hydronephrosis (p=0.017), band neutrophils accounting for >10% of the white blood cell count (p=0.001), hyperthermia or hypothermia (p=0.047), and a serum C-reactive protein concentration >100mg/L (p=0.002) were identified as independent risk factors for P. mirabilis bacteremic UTI. Seventeen patients died in hospital, including 11 in the bacteremic group and 6 in the nonbacteremic group. The bacteremic group had a higher mortality rate (p=0.016). Bacteremic UTI (p=0.049), shock (p=0.014), and a low body mass index (BMI) <18 kg/m(2) (p=0.033) were identified as independent risk factors for mortality. CONCLUSION Because bacteremic P. mirabilis UTIs are associated with higher mortality, clinicians should carefully manage cases that present with the risk factors for bacteremia, including community-acquired infection, hydronephrosis, band neutrophils accounting for >10% of the white blood cell count, hyperthermia or hypothermia, and a high level of C-reactive protein.

CXCL5/ENA78 increased cell migration and epithelial-to-mesenchymal transition of hormone-independent prostate cancer by early growth response-1/snail signaling pathway.

Prostate cancers that are resistant to hormone therapy are more invasive and have greater ability to spread to other organs than androgen‐dependent prostate cancers. Furthermore, this type of prostate cancer is also highly resistant to current forms of chemotherapy. This study analyzed CXCL5/ENA78, which is highly expressed in androgen‐independent prostate cancers, and is responsible for cell migration and epithelial‐to‐mesenchymal transition in two androgen‐independent prostate cancer cell lines. Inducement of PC‐3 and DU145 cancer progression by CXCL5/ENA78 is associated with increased Raf/MEK/ERK activation, and the upregulation of early growth response‐1 (Egr‐1) and Snail. Blockade of Egr‐1 decreased Snail upregulation and cell migration, indicating that Egr‐1 is required in CXCL5/ENA78‐mediated Snail enhancement and cell migration. In addition, Egr‐1 siRNA also decreased the effect of CXCL5/ENA78 on p27 inhibition, Cdk4 induction and cell proliferation, suggesting Egr‐1 is also involved in CXCL5/ENA78‐mediated cell growth. Moreover, blocking ERK1/2 by siRNA suppressed CXCL5/ENA78‐induced Egr‐1 enhancement, cell migration, and proliferation. Our study suggests that inhibition of CXCL5/ENA78‐mediated ERK/Egr‐1/Snail signaling is an attractive therapeutic target for androgen‐independent prostate cancer. J. Cell. Physiol. 226: 1224–1231, 2011.

Methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii on computer interface surfaces of hospital wards and association with clinical isolates.

BackgroundComputer keyboards and mice are potential reservoirs of nosocomial pathogens, but routine disinfection for non-water-proof computer devices is a problem. With better hand hygiene compliance of health-care workers (HCWs), the impact of these potential sources of contamination on clinical infection needs to be clarified.MethodsThis study was conducted in a 1600-bed medical center of southern Taiwan with 47 wards and 282 computers. With education and monitoring program of hand hygiene for HCWs, the average compliance rate was 74% before our surveillance. We investigated the association of methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Acinetobacter baumannii, three leading hospital-acquired pathogens, from ward computer keyboards, mice and from clinical isolates in non-outbreak period by pulsed field gel electrophoresis and antibiogram.ResultsOur results revealed a 17.4% (49/282) contamination rate of these computer devices by S. aureus, Acinetobacter spp. or Pseudomonas spp. The contamination rates of MRSA and A. baumannii in the ward computers were 1.1% and 4.3%, respectively. No P. aeruginosa was isolated. All isolates from computers and clinical specimens at the same ward showed different pulsotypes. However, A. baumannii isolates on two ward computers had the same pulsotype.ConclusionWith good hand hygiene compliance, we found relatively low contamination rates of MRSA, P. aeruginosa and A. baumannii on ward computer interface, and without further contribution to nosocomial infection. Our results suggested no necessity of routine culture surveillance in non-outbreak situation.

Zingiber officinale (ginger) compounds have tetracycline‐resistance modifying effects against clinical extensively drug‐resistant Acinetobacter baumannii

Extensively drug‐resistant Acinetobacter baumannii (XDRAB) is a growing and serious nosocomial infection worldwide, such that developing new agents against it is critical. The antimicrobial activities of the rhizomes from Zingiber officinale, known as ginger, have not been proven in clinical bacterial isolates with extensive drug‐resistance. This study aimed to investigate the effects of four known components of ginger, [6]‐dehydrogingerdione, [10]‐gingerol, [6]‐shogaol and [6]‐gingerol, against clinical XDRAB. All these compounds showed antibacterial effects against XDRAB. Combined with tetracycline, they showed good resistance modifying effects to modulate tetracycline resistance. Using the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging method, these four ginger compounds demonstrated antioxidant properties, which were inhibited by MnO2, an oxidant without antibacterial effects. After the antioxidant property was blocked, their antimicrobial effects were abolished significantly. These results indicate that ginger compounds have antioxidant effects that partially contribute to their antimicrobial activity and are candidates for use in the treatment of infections with XDRAB. Copyright

Dengue virus-associated hemophagocytic syndrome and dyserythropoiesis: a case report.

A 33‐year‐old man had dengue hemorrhagic fever with initial presentation of fever, leukocytosis, and thrombocytopenia. The cause of the subsequent rapid decline in red cell counts without evidence of intravascular hemolysis or massive bleeding was confirmed as hemophagocytosis and dyserythropoiesis by bone marrow study. The patient recovered with supportive care and the bone marrow pattern was normal on repeated bone marrow study. To our knowledge, this is the first reported case of dengue virus‐associated hemophagocytosis and dyserythropoiesis in Taiwan. Clinicians should consider that the occurrence of hemophagocytosis and dyserythropoiesis could be due to dengue virus infection. That this dengue virus infection was confirmed by a positive serology result at the convalescent stage but not at the acute symptomatic stage underlines the need for a second dengue serology study, as dengue infection can be missed due to an initial negative serology result.

Laboratory diagnostics of dengue fever: An emphasis on the role of commercial dengue virus nonstructural protein 1 antigen rapid test

BACKGROUND/PURPOSE(S) In 2008, the Dengue NS1 Ag STRIP (Bio-Rad Laboratories, Marnes-la-Coquette, France) was introduced to routine dengue diagnostics in Taiwan, in addition to real-time reverse-transcription polymerase chain reaction (PCR), virus isolation, and capture immunoglobulin (Ig)M/IgG enzyme-linked immunosorbent assay (ELISA). This study aimed to evaluate the benefit of this assay and factors influencing the results of these diagnostic tests. METHODS Retrospectively, the authors enrolled laboratory-confirmed adult dengue patients from July 2008 to January 2012 in a tertiary hospital. The sensitivities of each test alone and in combination were analyzed by the duration of illness (early stage: day 0-day 3 and late stage: day 4-day 8). The factors influencing sensitivity of the Dengue NS1 Ag STRIP were examined. RESULTS There were 392 patients enrolled. The overall sensitivity of the Dengue NS1 Ag STRIP was 68.37% and PCR was 71.94%. With the assistance of the Dengue NS1 Ag STRIP, a diagnosis was made in 10.97% of patients without the need for second convalescent samples, and 4.34% more cases were detected. Independent factors for reduced Dengue NS1 Ag STRIP sensitivity were dengue virus (DENV) IgG seropositivity and a sample taken after the fifth day of illness. At the early stage, the PCR and the Dengue NS1 Ag STRIP combination had the highest sensitivity rate than other combinations. At the late stage, a combination of the Dengue NS1 Ag STRIP and capture IgM/IgG ELISA had better sensitivity rates. PCR and capture IgM/IgG ELISA in combination had sensitivity above 90% through the course of illness. CONCLUSION Dengue NS1 Ag STRIP is a useful tool for early dengue diagnosis. Its use can increase the diagnostic sensitivity and decrease the need of convalescent samples. Seeking treatment late (days postonset > 4) and DENV IgG seropositivity independently decrease the sensitivity of the Dengue NS1 Ag STRIP.

Case report: Infective endocarditis caused by Brevundimonas vesicularis

BackgroundThere are few reports in the literature of invasive infection caused by Brevundimonas vesicularis in patients without immunosuppression or other predisposing factors. The choice of antimicrobial therapy for bacteremia caused by the pathogen requires more case experience to be determined.Case presentationThe case of a 40-year-old previously healthy man with subacute endocarditis proposed to be contributed from an occult dental abscess is described. The infection was found to be caused by B. vesicularis on blood culture results. The patient recovered without sequelae after treatment with ceftriaxone followed by subsequent ciprofloxacin therapy owing to an allergic reaction to ceftriaxone and treatment failure with ampicillin/sulbactam.ConclusionTo our knowledge, this is the first report of B. vesicularis as a cause of infective endocarditis. According to an overview of the literature and our experience, we suggest that third-generation cephalosporins, piperacillin/tazobactam, and ciprofloxacin are effective in treating invasive B. vesicularis infections, while the efficacy of ampicillin-sulbactam needs further evaluation.

Fatal Pasteurella multocida septicemia and necrotizing fasciitis related with wound licked by a domestic dog

A 68-y-old male had necrotizing fasciitis and bacteremia due to Pasteurella multocida. Saliva culture from his dog grew P. multocida and Pseudomonas aeruginosa. The human and dog P. multocida strains were of the same antibiogram but not identical tested with ribotyping. The wound licked by his dog was the only risk factor.

Clinical and Radiographic presentations of pulmonary cryptococcosis in immunocompetent patients.

Pulmonary cryptococcosis is often noted in immunocompromized patients, especially in HIV-seropositive patients and post-transplant patients. Only a few case reports and small-scale studies on pulmonary cryptococcosis in immunocompetent patients have been published in the English literature. However, there are several areas of uncertainty in this group of patients including image presentations and management strategy. This retrospective study including 17 patients is designed to share our 7 y of experience in clarifying the characteristics of pulmonary cryptococcosis in immunocompetent patients, including initial symptoms, diagnostic criteria, pulmonary imaging, treatment and outcome in a tertiary teaching hospital in Taiwan.