Biofilm-Forming by Carbapenem Resistant Enterobacteriaceae May Contribute to the Blood Stream Infection

Bloodstream infection (BSI) due to carbapenem-resistant Enterobacteriaceae (CRE) has a high mortality rate and is a serious threat worldwide. Ten CRE strains (eight Enterobacter cloacae, one Klebsiella pneumoniae and one Citrobacter freundii) were isolated from the blood of nine patients, a percentage of whom had been treated with indwelling devices. The steps taken to establish cause included minimum inhibitory concentration (MIC) tests, a pulsed-field gel electrophoresis (PFGE), biofilm study, a multiplex PCR for resistant genes of carbapenemases and extended-spectrum beta-lactamases (ESBLs), and plasmid incompatibility typing. All strains showed a tendency toward resistance to multiple antibiotics, including carbapenems. Frequently isolated genes of ESBLs and carbapenemases include blaTEM-1 (four strains), blaSHV-12 (four strains) and blaIMP-1 (six strains). A molecular analysis by PFGE was used to divide the XbaI-digested genomic DNAs of 10 CRE strains into eight patterns, and the analysis showed that three E. cloacae strains detected from two patients were either identical or closely related. The biofilm production of all CRE strains was examined using a microtiter biofilm assay, and biofilm growth in continuous flow chambers was observed via the use of a confocal laser scanning microscope. Our study indicates that biofilm formation on indwelling devices may pose a risk of BSI due to CRE

Invasive meningococcal disease due to a non-capsulated Neisseria meningitidis strain in a patient with IgG4-related disease

Abstract Background Invasive Meningococcal Disease (IMD) is a rare and critical disease in Japan. Most of these cases are caused by capsulated Neisseria meningitidis strains. Non-capsulated (non-typable) strains are considered relatively low-pathogenic and can colonize in the nasopharynx of healthy children and young adults. As far as could be ascertained, only twelve IMD cases due to non-capsulated strains have been reported in the literature. No clear risk factors could be identified in a literature review (unknown or immunocompetent, seven cases; C6 deficiency, three cases). Case presentation We report a Japanese male taxi driver with bacteremia and meningitis due to non-capsulated N. meningitidis. He had a fever and shaking chills. Ceftriaxone was administered, and the patient finally recovered. During the clinical course, relative adrenal insufficiency occurred and was treated with hydrocortisone. A hidden co-morbidity, immunoglobulin G4 (IgG4)-related disease, was revealed in the past surgical history (a resection of bilateral orbital tumors), which included symptoms (swelling lachrymal glands and lymph nodes), elevated IgG4, immunoglobulin E, and hypocomplementemia. He recovered finally and no recurrence was observed. Conclusions Our IMD case is the first reported in Japan, where IMD is not considered pandemic. The patient had a history of IgG4-related disease, although we could not establish a clear relationship between the patient’s IMD and co-morbidity. A collection of further clinical cases might establish the risk factors and characteristics of IMD that could be caused by this neglected pathogen, non-capsulated N. meningitidis

A small fragmented P protein of respiratory syncytial virus inhibits virus infection by targeting P protein

International audiencePeptide-based inhibitors hold promising potential in the development of antiviral therapy. Here, we investigated the antiviral potential of fragmented viral proteins derived from ribonucleoprotein (RNP) components of the human respiratory syncytial virus (HRSV). Based on a mimicking approach that targets the functional domains of viral proteins, we designed various fragments of nucleoprotein (N), matrix protein M2-1 and phosphoprotein (P) and tested the antiviral activity in an RSV mini-genome system. We found that the fragment comprising residues 130–180 and 212–241 in the C-terminal region of P (81 amino acid length), denoted as P Fr, significantly inhibited the polymerase activity through competitive binding to the full-length P. Further deletion analysis of P Fr suggested that three functional domains in P Fr (oligomerization, L-binding and nucleocapsid binding) are required for maximum inhibitory activity. More importantly, a purified recombinant P Fr displayed significant antiviral activity at low nanomolar range in RSV-infected HEp-2 cells. These results highlight P as an important target for the development of antiviral compounds against RSV and other paramyxoviruses

Epidemiology of Extended-Spectrum β-Lactamase Producing <i>Escherichia coli</i> in the Stools of Returning Japanese Travelers, and the Risk Factors for Colonization

<div><p>Objective</p><p>Travel overseas has recently been considered a risk factor for colonization with drug-resistant bacteria. The purpose of this study was to establish the epidemiology and risk factors associated with the acquisition of drug-resistant bacteria by Japanese travelers.</p><p>Methods</p><p>Between October 2011 and September 2012, we screened the stools of 68 Japanese returning travelers for extended-spectrum β-lactamase (ESBL) producing <i>Escherichia coli</i>. All specimens were sampled for clinical reasons. Based on the results, the participants were divided into an ESBL-producing <i>E. coli</i> positive group (18 cases; 26%) and an ESBL-producing <i>E. coli</i> negative group (50 cases; 74%), and a case-control study was performed. Microbiological analyses of ESBL-producing strains, including susceptibility tests, screening tests for metallo-β-lactamase, polymerase chain reaction amplification and sequencing of <i>bla</i>_CTX-M genes, multilocus sequence typing, and whole genome sequencing, were also conducted.</p><p>Results</p><p>In a univariate comparison, travel to India was a risk factor (Odds Ratio 13.6, 95% Confidence Interval 3.0–75.0, p<0.0001). There were no statistical differences in the characteristics of the travel, such as backpacking, purpose of travel, interval between travel return and sampling stool, and duration of travel. Although 10 of 13 analyzed strains (77%) produced CTX-M-15, no ST131 clone was detected.</p><p>Conclusion</p><p>We must be aware of the possibilities of acquiring ESBL-producing <i>E. coli</i> during travel in order to prevent the spread of these bacteria not only in Japan but globally.</p></div

The characteristics of ESBL-producing <i>E. coli</i> positive/negative groups in travelers to India.

1)<p>Student’s t-test, ²⁾ Fisher’s exact test.</p><p>ESBL = extended-spectrum β-lactamase; SD = standard deviation; VFR = visiting friends and relatives;</p