Wei-Ru Lin

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.

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

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.

Rapid control of a hospital-wide outbreak caused by extensively drug-resistant OXA-72-producing Acinetobacter baumannii.

Extensively drug‐resistant Acinetobacter baumannii (XDRAb) emerges as an important pathogen of health care–associated infections and outbreaks worldwide. During January and February 2006, there was a hospital‐wide outbreak of XDRAb at a medical center in Taiwan. Without limiting the usage of carbapenems or the closure of any ward, this outbreak was effectively controlled. We investigated the molecular epidemiology and reported the infection control experiences. XDRAb is defined as A baumannii that is resistant to multiple antibiotics but susceptible to tigecycline and polymyxin B. During the outbreak, the clinical and environmental XDRAb isolates were collected and studied by antimicrobial susceptibility testing, pulsed‐field gel electrophoresis, and polymerase chain reaction for Verona integron‐encoded metallo‐beta‐lactamases, imipenemases, and oxacillinases (OXA). Our measures to control the outbreak included private room isolation of patients until there were three successive negative cultures, reinforcement of contact precautions, daily environmental cleansing with room‐dedicated cleaning tools and sodium hypochlorite, and careful auditing of adherence. During the outbreak, 32 clinical XDRAb isolates came from 13 patients who were hospitalized in four intensive care units and three wards. Most (7 of 13, 53.8%) cases were associated with a surgical intensive care unit. The results from pulsed‐field gel electrophoresis study indicated that all isolates were of one genotype. All 32 isolates harbored ISAba1‐blaOxA‐51‐like and blaOxA‐72 genes. After this outbreak till August 2010, further incidences of XDRAb were sporadic cases of XDRAb with different clones and did not reach the level of outbreak. To our knowledge, this is the first reported hospital‐wide outbreak caused by OXA‐72 carbapenemase–producing A baumannii in the Asia‐Pacific region, with successful and sustained control. Although the source or vehicle of the outbreak was not identified, our results suggest that a hospital‐wide outbreak can be successfully managed with strict infection control measures, and that the limitation of the use of carbapenems and closure of wards may not be necessary.

Why is In-hospital Diagnosis of Pulmonary Tuberculosis Delayed in Southern Taiwan?

BACKGROUND/PURPOSE In-hospital diagnosis delay (IHDD) of pulmonary tuberculosis (TB) has a significant impact on nosocomial TB transmission. We investigated the risk factors associated with prolonged IHDD in Taiwan, a high-resource, mid-incidence area. METHODS Between January 2005 and August 2006, we retrospectively enrolled 193 consecutive hospitalized patients. All of them had culture-proven pulmonary TB and did not receive antitubercular treatment at admission. IHDD was defined as the interval between admission and initiation of antitubercular treatment. Patients were grouped according to the median value of IHDD. RESULTS The median IHDD was 7 days. Patients with IHDD > 7 days were considered the prolonged-delay group, and those with IHDD <or= 7 days, the short-delay group. Independent risk factors [with adjusted odd ratios (95% confidence intervals)] for prolonged IHDD were: negative sputum smear [47.53 (13.20-171.18), p < 0.001]; non-cavitary lesions on chest radiographs [14.90 (3.46-64.14), p < 0.001]; admission to hospital departments other than chest medicine/infectious diseases [6.60 (1.95-22.41), p = 0.002]; exposure to fluoroquinolones before antitubercular treatment [5.29 (1.13-24.75), p = 0.034]; underlying malignancy [4.59 (1.13-18.67), p = 0.033); and age > 65 years [3.19 (1.01-10.05), p = 0.048]. Death attributed to tuberculosis was associated with positive sputum smear (hazard ratio = 21.85; 95% CI = 2.74-174.44; p = 0.004) but not prolonged IHDD (p = 0.325). CONCLUSION To minimize IHDD, clinicians should carefully manage hospitalized patients with risk factors for prolonged delay, such as those with negative sputum smears, non-cavitary lesions on chest radiographs, admission to departments other than chest medicine/infectious diseases, exposure to fluoroquinolones before antitubercular treatment, underlying malignancy, and age > 65 years.

Sphingomonas paucimobilis bacteraemia and septic arthritis in a diabetic patient presenting with septic pulmonary emboli

Sphingomonas paucimobilis, a yellow-pigmented, aerobic, glucose non-fermenting, Gram-negative bacillus, is a rare cause of human infection normally associated with immunocompromised hosts. We report a case of bacteraemia and septic arthritis in a 47-year-old diabetic man who presented with septic pulmonary emboli due to S. paucimobilis. The patient had an initial presentation of fever, right knee pain, coughing, dyspnoea and chest pain. The infection was treated successfully by surgical debridement combined with meropenem plus ciprofloxacin, based on the patients antibiotic susceptibility profile. To our knowledge, this is the first case report for septic pulmonary emboli having arisen from an S. paucimobilis infection.

Stenotrophomonas maltophilia bloodstream infection: Comparison between community-onset and hospital-acquired infections

BACKGROUND/PURPOSE Stenotrophomonas maltophilia has been recognized as an important nosocomial pathogen, but few reports have discussed S. maltophilia infection in the community settings. This study aimed to reveal characteristics of patients with community-onset S. maltophilia bloodstream infection (SMBSI), to specify the subgroup of healthcare-associated (HCA) infection in the community-onset group and to compare them with hospital-acquired (HA) SMBSI patients. MATERIALS AND METHODS Medical charts of adult patients with SMBSI presenting to a medical center in southern Taiwan from May 2008 to October 2011 were reviewed and analyzed retrospectively. RESULTS Among 153 patients, we observed a high percentage (38.6%) of SMBSI to be community onset. Among community-onset SMBSI, 45.8% were community-acquired (CA) and 54.2% were HCA. The crude mortality rates were 11.1%, 18.8%, and 60.6% in the CA, HCA, and HA groups, respectively. Structural/mechanical abnormalities were observed in 32.7% of all cases, and 60% of those were related to malignancy. Independent risk factors for mortality in community-onset SMBSI were liver cirrhosis, liver metastasis, and a high Pitt bacteremia score, whereas structural/mechanical abnormalities and a high Pitt bacteremia score related to increased mortality in HA SMBSI. CONCLUSION Community-onset S. maltophilia infection deserves attention. Patients with community-onset SMBSI have reduced disease severity and lower mortality rate when compared to HA SMBSI. Underlying structural/mechanical abnormalities, especially those caused by malignancies, are common in SMBSI cases and should be investigated when bacteremia occurs.

Effects of Gender and Age on Development of Concurrent Extrapulmonary Tuberculosis in Patients with Pulmonary Tuberculosis: A Population Based Study

Most cases of adult-onset tuberculosis (TB) result from reactivation of a pre-existing Mycobacterium tuberculosis infection. Mycobacterium tuberculosis usually invades the respiratory tract and most patients develop intrapulmonary TB; however, some patients develop concurrent pulmonary and extra-pulmonary TB. The purpose of the present study was to identify the demographic and clinical factors associated with an increased risk of concurrent extra-pulmonary diseases in patients with pulmonary TB. We compared patients who had isolated pulmonary TB with patients who had concurrent pulmonary and extra-pulmonary TB. We initially analyzed one-million randomly selected subjects from the population-based Taiwan National Health Insurance database. Based on analysis of 5414 pulmonary TB patients in this database, women were more likely than men to have concurrent extra-pulmonary TB (OR: 1.30, p = 0.013). A separate analysis of the Kaohsiung Medical University Hospital database, which relied on sputum culture-proven pulmonary TB, indicated that women were more likely than men to have concurrent extra-pulmonary TB (OR: 1.62, p = 0.039). There was no significant gender difference in extra-pulmonary TB for patients younger than 45 years in either database. However, for patients 45 years and older, women were more likely than men to have concurrent extra-pulmonary TB (insurance database: 9.0% vs. 6.8%, p = 0.016, OR: 1.36; hospital database: 27.3% vs. 16.0%, p = 0.008, OR = 1.98). Our results indicate that among patients who have pulmonary TB, older females have an increased risk for concurrent extra-pulmonary TB.