Nosocomial person-to-person transmission of severe fever with thrombocytopenia syndrome.

OBJECTIVES: This study is an epidemiologic investigation of nosocomial severe fever with thrombocytopenia syndrome virus (SFTSV) transmission among healthcare workers (HCWs) after contact with an index patient. The aim of this study was to determine whether exposure to blood or bloody respiratory secretion is associated with human-to-human transmission of SFTSV. METHODS: Eleven days after the index patient died, two HCWs who had close exposure to the patient presented with typical symptoms of SFTS. An epidemiological investigation was conducted on all 25 HCWs who had been in close contact with the index patient. Clinical and laboratory data were collected, and transmission rate before and after the index patient had haemorrhagic manifestations was analysed. RESULTS: Among 25 HCWs who had direct contact with the index patient, five HCWs were confirmed to have SFTS. All five HCWs had contact to blood or bloody respiratory secretions of the index patient without adequate use of personal protective equipment (PPE). No HCW with contact before haemorrhagic manifestations of the index patient contracted SFTS. Overall, the transmission rate was higher for HCWs who had contact after the index patient had haemorrhagic manifestations (33.3%, five of 15 HCWs, vs. 0%, zero of ten HCWs, p 0.041). CONCLUSIONS: In HCWs who are inadequately protected, person-to-person transmission of SFTSV may be associated with contact with blood or bloody respiratory secretions. Therefore, universal precaution and full PPE is highly recommended for protection against SFTSV when there are signs of bleeding.

The gamma-glutamyl transferase to platelet ratio and the FIB-4 score are noninvasive markers to determine the severity of liver fibrosis in chronic hepatitis B infection.

Objective Noninvasive liver fibrosis evaluation is an important issue in chronic hepatitis B infection, and may be assessed using transient elastography (Fibroscan) or with blood markers. We compared the value of Fibroscan with that of a panel of routine serum markers. Materials and methods We recruited 278 chronic hepatitis B patients who underwent Fibroscan and HBV DNA testing. Fibroscan assessments were made, and blood taken for the measurement of the gamma-glutamyl transferase (GGT) to platelet ratio (GPR), platelet count, aspartate aminotransaminase (AST), alanine aminotransaminase (ALT), international normalised ratio (INR), total cholesterol, trigylcerides, bilirubin, mean platelet volume (MPV), AST to platelet ratio index (APRI) and neutrophil to lymphocyte ratio. Results A fibrosis index based on four factors (FIB-4) and GPR were higher and platelets were lower in mild liver fibrosis than in non-liver fibrosis. GGT, AST, ALT, INR, MPV, APRI, FIB-4, GPR, and NLR were higher, and platelet and cholesterol were lower in severe liver fibrosis than in mild liver fibrosis. Elevated GPR (Odds ratio 95% CI 9.1 [1.66-50.0] p = 0.011) and FIB-4 (2.3 [1.2-4.2], p = 0.01) were associated with greater risk of liver fibrosis. The areas under the curve (AUC) were for GPR 0.84 at a cut-off of 0.299 and for FIB-4 0.82 at cut-off 1.571. Conclusions FIB-4 and GPR may be useful blood markers for evaluating the severity of liver fibrosis in chronic hepatitis B patients. Further prospective study is required to validate these noninvasive blood markers in a clinical practice.

Quantamatrix Multiplexed Assay Platform system for direct detection of bacteria and antibiotic resistance determinants in positive blood culture bottles.

OBJECTIVES: Rapid and accurate identification of the causative pathogens of bloodstream infections (BSIs) is crucial for initiating appropriate antimicrobial therapy, which decreases the related morbidity and mortality rates. The aim of this study was to evaluate the usefulness of a newly developed multiplexed, bead-based bioassay system, the Quantamatrix Multiplexed Assay Platform (QMAP) system, obtained directly from blood culture bottles, to simultaneously detect the presence of bacteria and identify the genes for antibiotic resistance. METHODS: The QMAP system was used to evaluate 619 blood culture bottles from patients with BSIs and to compare the results of conventional culture methods. RESULTS: Using conventional bacterial cultures as the reference standard, the sensitivity, specificity, positive predictive value, and negative predictive value of the QMAP system for detection of bacterial pathogens in positive blood culture (PBC) samples were 99.8% (n=592, 95% CI 0.9852-1.000, p <0.001), 100% (95% CI 0.983-1.000, p <0.001), 100% (95% CI 0.9922-1.000, p <0.001), and 99.5% (95% CI 0.9695-1.000, p <0.001), respectively. In addition, sensitivity and specificity of the QMAP system for identification of the genes for antibiotic resistance were 99.4% (n=158, 95% CI 0.9617-0.9999, p <0.009) and 99.6% (95% CI 0.9763-0.9999, p <0.0001), respectively. CONCLUSIONS: Obtaining results using the QMAP system takes about 3 hr, while culture methods can take 48-72 hr. Therefore, analysis using the QMAP system is rapid and reliable for characterizing causative pathogens in BSIs.

Performance of PCR-REBA assay for screening and identifying pathogens directly in whole blood of patients with suspected sepsis.

AIMS: Rapid and accurate identification of a broad range of bacterial and fungal pathogens is the key to successful management of patients with bloodstream infections (BSIs). The aim of this study was to evaluate the diagnostic performance of PCR-REBA Sepsis-ID test for the detection of BSIs pathogens. METHODS AND RESULTS: EDTA anticoagulated blood for REBA Sepsis-ID assay and blood culture samples from 882 patients with suspected sepsis were simultaneously collected from January 2014 to December 2014. Of 115 patients with positive blood culture, 64 (55·7%) were Gram-positive bacteria, 35 (30·4%) were Gram-negative bacteria, 1 (0·9%) was Candida albicans and 15 (13·0%) were polymicrobial infections. The concordance rate of blood culture system and PCR-REBA Sepsis ID test was 83·0% (95% confidence interval (CI), 79·8-84·8, P < 0·0001). Compared to blood culture, the diagnosis of bacterial proven pathogens by PCR-REBA revealed 81·0% (95% CI, 73·4-86·8, P < 0·0001) sensitivity, 83·4% (95% CI, 80·0-85·4, P < 0·0001) specificity, 80·9% positive and 95·8% negative predictive values respectively. In 10 cases with PCR-REBA positive but blood culture negative, the levels of C-reactive protein were significantly elevated 18·5 mg dl(-1) (SD ± 13·7, 95% CI 1·8-41·9) and six cases has been proven to have pathogen by bacterial 16S rRNA sequencing. Although the sensitivity for pathogen identification was not significantly different between PCR-REBA and blood culture (P = 0·5), the combination of the two methods resulted in a significantly increased rate of pathogen detection (P = 0·002). The results of this study suggested that PCR-REBA may be helpful when added to blood culture in the diagnosis and management of sepsis. CONCLUSIONS: PCR-REBA Sepsis-ID test is a useful tool for the rapid identification of pathogenic isolates in whole blood to ensure adequate treatment for the causative agents of BSIs. SIGNIFICANCE AND IMPACT OF THE STUDY: Although the cost of molecular diagnostic assays is higher than the cost of conventional methods, clinical and economic cost-benefit analysis is still needed. PCR-REBA may provide essential information for accelerating therapeutic decisions to ensure effective treatment with antibiotics in the acute phase of pathogen infection.

Comparable characteristics of tuberculous and non-tuberculous mycobacterial cavitary lung diseases.

OBJECTIVE: To identify characteristics that differentiate lung disease due to non-tuberculous mycobacteria (NTM) from that due to pulmonary tuberculosis (PTB) in acid-fast bacilli (AFB) smear-positive patients with lung cavities. METHODS: From 2006 to 2012, 142 AFB smear- and culture-positive patients with lung cavities were identified at the Wonju Severance Christian Hospital, Wonju, Korea. Clinical and radiographic characteristics were compared between patients with NTM disease and PTB. RESULTS: Of 142 patients, 112 were diagnosed with PTB and 30 with NTM disease. Patients with NTM disease were older (62 vs. 49 years, P = 0.001), more likely to have had previous anti-tuberculosis treatment (18, 60.0% vs. 34, 30.6%; P = 0.001), more likely to have haemoptysis (9, 30.0% vs. 13, 11.9%; P = 0.022) and less likely to have consolidation on chest radiograph (20, 66.7% vs. 98, 87.5%; P = 0.007) than PTB patients. Multivariate analysis showed that age ≥65 years (OR 3.37, 95%CI 1.24-9.13, P = 0.010) and previous anti-tuberculosis treatment (OR 3.75, 95%CI 1.46-9.65, P = 0.006) were significantly associated with NTM disease. CONCLUSIONS: Cavitary patients with positive AFB smears and NTM or PTB had considerable overlapping clinical characteristics, although patients aged ≥65 years or with a previous history of anti-tuberculosis treatment were more likely to have NTM.

Acquisition of extensive drug-resistant Pseudomonas aeruginosa among hospitalized patients: risk factors and resistance mechanisms to carbapenems.

Extensive drug-resistant Pseudomonas aeruginosa (XDRPA) strains, defined as resistant to all available antipseudomonal antibiotics, have been reported recently. This study aimed to investigate the risk factors for XDRPA acquisition by patients and the resistance mechanisms to carbapenems. From June to November 2007, XDRPA isolates were collected from patients in eight tertiary care hospitals. A case-control study was performed to determine factors associated with XDRPA acquisition. EDTA-imipenem disc synergy tests, and polymerase chain reaction amplification and sequencing were performed to detect the presence of metallo-ß-lactamases (MBLs). Risk factor analysis was performed for 33 patients. Mechanical ventilation [odds ratio (OR) 8.2, 95% confidence interval (CI) 1.3-52.2; P = 0.026] and APACHE II score (OR 1.2, 95% CI 1.0-1.3; P = 0.007) were identified as independent risk factors for XDRPA acquisition. Pulsed-field gel electrophoresis of XDRPA identified clonal epidemic isolates co-existing with sporadic isolates. Eight of 43 (19%) XDRPA isolates were shown to produce MBLs; four produced VIM-2 and four produced IMP-6. This study suggests a major role for mechanical ventilation in XDRPA acquisition. Moreover, pulsed-field gel electrophoresis identified a clonal epidemic within hospitals. Taken together, these results suggest that patient-to-patient transmission contributes to XDRPA acquisition in Korea.

K5.76Ga5.76Si10.24O32.3.4H2O, a gallosilicate with the zeolite gismondine topology.

The title compound, K-GaSi-GIS, potassium gallium silicon oxide hydrate, was synthesized hydrothermally and its crystal structure was determined from data collected on a single crystal of dimensions 10 x 10 x 8 microm at a synchrotron X-ray source. The compound, which has the aluminosilicate (AlSi) zeolite gismondine (GIS) topology, Ca(4)[Al(8)Si(8)O(32)].16H(2)O, crystallizes in the tetragonal space group I4(1)/a. A disordered distribution of the framework Si/Ga sites leads to higher symmetry of the GIS-type network compared with the usual monoclinic symmetry in AlSi-GIS. Framework Ga substitution for Al in AlSi-GIS leads to substantial distortion of the crankshaft chains, reducing the effective pore dimensions and suggesting the possibility of pore-dimension control via partial framework-cation substitution.

Emerging erythromycin resistance among group B streptococci in Korea.

In order to determine possible trends in the susceptibility and distribution of group B streptococci (GBS) serotypes in a Korean population and to elucidate any relationship between the serotypes and the antimicrobial susceptibility patterns found, 185 clinical isolates of GBS were investigated between 1990 and 1998. The rate of erythromycin resistance increased from 0% during the period 1990-1995 to 26% in 1996 and 40% in 1998. The overall rates of resistance to erythromycin and clindamycin were 20% and 22.2%, respectively. GBS serotype V was not detected until 1995, but it was isolated in 1996 and ranked third in frequency (18.8%) in 1997. Among the 37 erythromycin-resistant strains detected, 54.1% and 29.7% were of serotype III and V, respectively. The emerging erythromycin resistance detected among these GBS isolates was mainly due to a sudden increase in the incidence of GBS serotypes with multidrug-resistant phenotypes.

Colonization rates and serotypes of group B streptococci isolated from pregnant women in a Korean tertiary hospital.

In a study designed to provide data on the rates of maternal carriage of group B streptococci (GBS) in Korean women, vaginal, anorectal, and urethral swab specimens from 459 pregnant women and ear canal and umbilicus swabs from their 288 neonates were cultured with new Granada medium and selective Todd-Hewitt broth. Additionally, the serotypes of 64 isolates of GBS and the minimal inhibitory concentrations of seven antimicrobial agents for these isolates were determined. The rate of colonization by GBS in pregnant women and in their babies was 5.9% (27/459) and 0.7% (2/288), respectively. The rates of resistance of GBS isolated from pregnant women were 13.3% to clindamycin, 5% to erythromycin, and 98.3% to tetracycline. The majority of GBS isolates from pregnant women belonged to serotypes Ib (48.3%), Ia (24.1%), and III (20.7%).