Mise ŕ jour le : 14-02-2012
Les derniers abstracts de la revue JCM Current Issue : |
Date de mise en ligne : Vendredi 20 janvier 2012
Burd, E. M., Sharp, S. E.
Photo Quiz: A 36-Year-Old with Recurrent Conjunctivitis [Photo Quiz]
Date de mise en ligne : Vendredi 20 janvier 2012 "Classical" Whipple's disease (cWD) is caused by Tropheryma whipplei and is characterized by arthropathy, weight loss, and diarrhea. T. whipplei infectious endocarditis (TWIE) is rarely reported, either in the context of cWD or as isolated TWIE without signs of systemic infection. The frequency of TWIE is unknown, and systematic studies are lacking. Here, we performed an observational cohort study on the incidence of T. whipplei infection in explanted heart valves in two German university centers. Cardiac valves from 1,135 patients were analyzed for bacterial infection using conventional culture techniques, PCR amplification of the bacterial 16S rRNA gene, and subsequent sequencing. T. whipplei-positive heart valves were confirmed by specific PCR, fluorescence in situ hybridization, immunohistochemistry, histological examination, and culture for T. whipplei. Bacterial endocarditis was diagnosed in 255 patients, with streptococci, staphylococci, and enterococci being the main pathogens. T. whipplei was the fourth most frequent pathogen, found in 16 (6.3%) cases, and clearly outnumbered Bartonella quintana, Coxiella burnetii, and members of the HACEK group (Haemophilus species, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae). In this cohort, T. whipplei was the most commonly found pathogen associated with culture-negative infective endocarditis.
Geissdorfer, W., Moos, V., Moter, A., Loddenkemper, C., Jansen, A., Tandler, R., Morguet, A. J., Fenollar, F., Raoult, D., Bogdan, C., Schneider, T.
High Frequency of Tropheryma whipplei in Culture-Negative Endocarditis [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 The emergence of carbapenem resistance in Enterobacteriaceae has become a great concern. The aim of this study was to characterize ertapenem-resistant Enterobacter cloacae isolates from a Taiwanese university hospital. A total of 355 nonduplicated E. cloacae isolates collected in 2007 were analyzed by antimicrobial susceptibility testing with and without an inhibitor of efflux pumps and AmpC β-lactamase. The phenotype of extended-spectrum β-lactamase (ESBL), profile of outer membrane proteins (OMPs), and clonal relatedness were investigated by the double-disk synergy test, urea/SDS-PAGE, and pulsed-field gel electrophoresis (PFGE), respectively. β-Lactamase genes were examined by PCR and sequencing, and the expression of efflux pump gene acrB was evaluated by reverse transcription-PCR. The contribution of porin deficiency to resistance was investigated by restoring functional porin genes on plasmids. We demonstrated that ertapenem resistance was prevalent (53/355; 14.9%) in E. cloacae. Among the strains, IMP-8, SHV-12, and TEM-1 β-lactamases were identified in 3 (5.7%), 40 (75.5%), and 46 (86.8%) isolates, respectively. PFGE showed clonal diversity among these isolates. Phenotypes of ESBL, AmpC β-lactamase overproduction, an active efflux pump, and change in the expression of OMPs were found in 18 (34%), 11 (20.8%), 51 (96.2%), and 23 (43.4%) of ertapenem-resistant strains, respectively. Ertapenem MICs were restored in strains with OmpC and OmpF expression plasmids. This study suggests that ESBL, AmpC β-lactamase overproduction, and decreased OMP expression combined with an active efflux pump contribute to the ertapenem resistance of E. cloacae. The presence of IMP-8 may also play a partial role in ertapenem resistance in Taiwan.
Yang, F.-C., Yan, J.-J., Hung, K.-H., Wu, J.-J.
Characterization of Ertapenem-Resistant Enterobacter cloacae in a Taiwanese University Hospital [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 Quantitative PCR (qPCR) is more sensitive than microscopy for detecting Pneumocystis jirovecii in bronchoalveolar lavage (BAL) fluid. We therefore developed a qPCR assay and compared the results with those of a routine immunofluorescence assay (IFA) and clinical data. The assay included automated DNA extraction, amplification of the mitochondrial large-subunit rRNA gene and an internal control, and quantification of copy numbers with the help of a plasmid clone. We studied 353 consecutive BAL fluids obtained for investigation of unexplained fever and/or pneumonia in 287 immunocompromised patients. No qPCR inhibition was observed. Seventeen (5%) samples were both IFA and qPCR positive, 63 (18%) were IFA negative and qPCR positive, and 273 (77%) were both IFA and qPCR negative. The copy number was significantly higher for IFA-positive/qPCR-positive samples than for IFA-negative/qPCR-positive samples (4.2 ± 1.2 versus 1.1 ± 1.1 log10 copies/μl; P < 10–4). With IFA as the standard, the qPCR assay sensitivity was 100% for ≥2.6 log10 copies/μl and the specificity was 100% for ≥4 log10 copies/μl. Since qPCR results were not available at the time of decision-making, these findings did not trigger cotrimoxazole therapy. Patients with systemic inflammatory diseases and IFA-negative/qPCR-positive BAL fluid had a worse 1-year survival rate than those with IFA-negative/qPCR-negative results (P < 10–3), in contrast with solid-organ transplant recipients (P = 0.88) and patients with hematological malignancy (P = 0.26). Quantifying P. jirovecii DNA in BAL fluids independently of IFA positivity should be incorporated into the investigation of pneumonia in immunocompromised patients. The relevant threshold remains to be determined and may vary according to the underlying disease.
Botterel, F., Cabaret, O., Foulet, F., Cordonnier, C., Costa, J.-M., Bretagne, S.
Clinical Significance of Quantifying Pneumocystis jirovecii DNA by Using Real-Time PCR in Bronchoalveolar Lavage Fluid from Immunocompromised Patients [Mycology]
Date de mise en ligne : Vendredi 20 janvier 2012 Genotyping of cytomegalovirus (CMV) is useful to examine potential differences in the pathogenicity of strains and to demonstrate coinfection with multiple strains involved in CMV disease in adults and congenitally infected newborns. Studies on genotyping of CMV in dried blood spots (DBS) are rare and have been hampered by the small amount of dried blood available. In this study, two multiplex real-time PCR assays for rapid gB and gH genotyping of CMV in DBS were developed. Validation of the assays with 39 CMV-positive plasma samples of transplant recipients and 21 urine specimens of congenitally infected newborns was successful in genotyping 100% of the samples, with gB1 and gB3 being the most prevalent genotypes. Multiple gB and gH genotypes were detected in 36% and 33% of the plasma samples, respectively. One urine sample from a newborn with symptomatic congenital CMV was positive for gB1 and gB2. DBS of congenitally infected newborns (n = 41) were tested using 9 μl of dried blood, and genotypes were detected in 81% (gB) and 73% (gH) of the samples, with gB3 being the most prevalent genotype. No clear association of specific genotypes with clinical outcome was observed. In conclusion, the CMV gB and gH PCR assays were found to be rapid, sensitive for detecting mixed infections, and suitable for direct usage on DBS. These assays are efficient tools for genotyping of CMV in DBS of congenitally infected newborns.
de Vries, J. J. C., Wessels, E., Korver, A. M. H., van der Eijk, A. A., Rusman, L. G., Kroes, A. C. M., Vossen, A. C. T. M.
Rapid Genotyping of Cytomegalovirus in Dried Blood Spots by Multiplex Real-Time PCR Assays Targeting the Envelope Glycoprotein gB and gH Genes [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Complicated skin and soft tissue infections (cSSTIs) are among the most rapidly increasing reasons for hospitalization. To describe inpatients with regard to patient characteristics, cSSTI origin, appropriateness of initial antibiotics, and outcomes, we performed a retrospective cohort study in patients hospitalized for cSSTI. To identify independent predictors of outcomes, we performed multivariate analyses. Of 1,096 eligible patients, 48.7% had health care-associated (HCA) cSSTI and 51.3% had community-acquired (CA) cSSTI. After adjustment for baseline variables, hospital length of stay (LOS) was longer for HCA than for CA cSSTI (difference, 2.1 days; 95% confidence interval [CI], 0.8 to 3.5; P < 0.05). Other covariates associated with a longer LOS were need for dialysis (regression coefficient ± standard error, 4.5 ± 1.1) and diabetic wound diagnosis (2.6 ± 1.0) (all P < 0.05). In the subset with culture-positive cSSTI within 24 h of admission, the most common pathogen was Staphylococcus aureus (298/449 [66.4%]), of which 74.8% (223/298) were methicillin-resistant S. aureus (MRSA). Eighty-three patients (18.5%) received inappropriate initial antibiotics. After adjustment for other variables, the following were associated with inappropriate initial therapy: direct admission to hospital (not via emergency department), cSSTI caused by MRSA or mixed pathogens, and cSSTI caused by pathogens other than S. aureus or streptococci (all P < 0.05). We did not find an association between inappropriate therapy and outcomes, except in the subset with ulcers (adjusted odds ratio, 11.8; 95% CI, 1.3 to 111.1; P = 0.03). More studies are needed to examine the impact of HCA cSSTI and inappropriate initial therapy on outcomes.
Zervos, M. J., Freeman, K., Vo, L., Haque, N., Pokharna, H., Raut, M., Kim, M.
Epidemiology and Outcomes of Complicated Skin and Soft Tissue Infections in Hospitalized Patients [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 Persistent infections by high-risk human papillomaviruses (HPVs) are the main etiological factor for cervical cancer, and expression of HPV E7 oncoproteins was suggested to be a potential marker for tumor progression. The objective of this study was to generate new reagents for the detection of the HPV18 E7 oncoprotein in cervical smears. Rabbit monoclonal antibodies against recombinant E7 protein of HPV type 18 (HPV18) were generated and characterized using Western blotting, epitope mapping, indirect immunofluorescence, and immunohistochemistry. One clone specifically recognizing HPV18 E7 was used for the development of a sandwich enzyme-linked immunosorbent assay (ELISA). The assay was validated using recombinant E7 proteins of various HPV types and lysates from E7-positive cervical carcinoma cells. A total of 14 HPV18 DNA-positive cervical swab specimens and 24 HPV DNA-negative-control specimens were used for the determination of E7 protein levels by the newly established sandwich ELISA. On the basis of the average absorbance values obtained from all 24 negative controls, a cutoff above which a clinical sample can be judged E7 positive was established. Significant E7 signals 6- to 30-fold over background were found in 7 out of 14 abnormal HPV18 DNA-positive cervical smear specimens. This feasibility study demonstrates for the first time that HPV18 E7 oncoprotein can be detected in cervical smears.
Ehehalt, D., Lener, B., Pircher, H., Dreier, K., Pfister, H., Kaufmann, A. M., Frangini, S., Ressler, S., Muller-Holzner, E., Schmitt, M., Hofler, D., Rostek, U., Kaiser, A., Widschwendter, A., Zwerschke, W., Jansen-Durr, P.
Detection of Human Papillomavirus Type 18 E7 Oncoprotein in Cervical Smears: a Feasibility Study [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Cellular human immunodeficiency virus type 1 (HIV-1) DNA may be considered a marker of disease progression with significant predictive power, but published data on its correlation with plasma HIV RNA levels and CD4 counts in acute and chronic patients are not conclusive. We evaluated a cohort of 180 patients naïve for antiretroviral therapy before the beginning of treatment and after a virological response in order to define the indicators correlated with HIV DNA load decrease until undetectability. The following variables were evaluated as continuous variables: age, CD4 cell count and log10 HIV DNA level at baseline and follow-up, and baseline log10 HIV RNA level. Primary HIV infection at the start of therapy, an HIV RNA level at follow-up of <2.5 copies/ml, origin, gender, and transmission risk were evaluated as binary variables. The decline of HIV DNA values during effective therapy was directly related to baseline HIV DNA and HIV RNA values, to an increase in the number of CD4 cells, and to the achievement of an HIV RNA load of <2.5 copies/ml. An undetectable cellular HIV DNA load was achieved by 21.6% of patients at the follow-up time point and correlated significantly with lower baseline cellular HIV DNA values and with being in the primary stage of infection when therapy started. In conclusion, early treatment facilitated the achievement of undetectable levels of plasma viremia and cellular HIV DNA and a better recovery of CD4 lymphocytes. HIV DNA levels before and during highly active antiretroviral therapy may be used as a new tool for monitoring treatment efficacy.
Parisi, S. G., Andreis, S., Mengoli, C., Scaggiante, R., Ferretto, R., Manfrin, V., Cruciani, M., Giobbia, M., Boldrin, C., Basso, M., Andreoni, M., Palu, G., Sarmati, L.
Baseline Cellular HIV DNA Load Predicts HIV DNA Decline and Residual HIV Plasma Levels during Effective Antiretroviral Therapy [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 The relationship between carriage and the development of invasive meningococcal disease is not fully understood. We investigated the changes in meningococcal carriage in 892 military recruits in Finland during a nonepidemic period (July 2004 to January 2006) and characterized all of the oropharyngeal meningococcal isolates obtained (n = 215) by using phenotypic (serogrouping and serotyping) and genotypic (porA typing and multilocus sequence typing) methods. For comparison, 84 invasive meningococcal disease strains isolated in Finland between January 2004 and February 2006 were also analyzed. The rate of meningococcal carriage was significantly higher at the end of military service than on arrival (18% versus 2.2%; P < 0.001). Seventy-four percent of serogroupable carriage isolates belonged to serogroup B, and 24% belonged to serogroup Y. Most carriage isolates belonged to the carriage-associated ST-60 clonal complex. However, 21.5% belonged to the hyperinvasive ST-41/44 clonal complex. Isolates belonging to the ST-23 clonal complex were cultured more often from oropharyngeal samples taken during the acute phase of respiratory infection than from samples taken at health examinations at the beginning and end of military service (odds ratio [OR], 6.7; 95% confidence interval [95% CI], 2.7 to 16.4). The ST-32 clonal complex was associated with meningococcal disease (OR, 17.8; 95% CI, 3.8 to 81.2), while the ST-60 clonal complex was associated with carriage (OR, 10.7; 95% CI, 3.3 to 35.2). These findings point to the importance of meningococcal vaccination for military recruits and also to the need for an efficacious vaccine against serogroup B isolates.
Jounio, U., Saukkoriipi, A., Bratcher, H. B., Bloigu, A., Juvonen, R., Silvennoinen-Kassinen, S., Peitso, A., Harju, T., Vainio, O., Kuusi, M., Maiden, M. C. J., Leinonen, M., Kayhty, H., Toropainen, M.
Genotypic and Phenotypic Characterization of Carriage and Invasive Disease Isolates of Neisseria meningitidis in Finland [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 Trained African giant-pouched rats (Cricetomys gambianus) can detect Mycobacterium tuberculosis and show potential for the diagnosis of tuberculosis (TB). However, rats' ability to discriminate between clinical sputum containing other Mycobacterium spp. and nonmycobacterial species of the respiratory tract is unknown. It is also unknown whether nonmycobacterial species produce odor similar to M. tuberculosis and thereby cause the detection of smear-negative sputum. Sputum samples from 289 subjects were analyzed by smear microscopy, culture, and rats. Mycobacterium spp. were isolated on Lowenstein-Jensen medium, and nonmycobacterial species were isolated on four different media. The odor from nonmycobacterial species from smear- and M. tuberculosis culture-negative sputa detected by ≥2 rats ("rat positive") was analyzed by gas chromatography-mass spectrometry and compared to the M. tuberculosis odor. Rats detected 45 of 56 confirmed cases of TB, 4 of 5 suspected cases of TB, and 63 of 228 TB-negative subjects (sensitivity, 80.4%; specificity, 72.4%; accuracy, 73.9%; positive predictive value, 41.7%; negative predictive value, 93.8%). A total of 37 (78.7%) of 47 mycobacterial isolates were M. tuberculosis complex, with 75.7% from rat-positive sputa. Ten isolates were nontuberculous mycobacteria, one was M. intracellulare, one was M. avium subsp. hominissuis, and eight were unidentified. Rat-positive sputa with Moraxella catarrhalis, Streptococcus pneumoniae, Staphylococcus spp., and Enterococcus spp. were associated with TB. Rhodococcus, Nocardia, Streptomyces, Staphylococcus, and Candida spp. from rat-positive sputa did not produce M. tuberculosis-specific volatiles (methyl nicotinate, methyl para-anisate, and ortho-phenylanisole). Prevalence of Mycobacterium-related Nocardia and Rhodococcus in smear-negative sputa did not equal that of smear-negative mycobacteria (44.7%), of which 28.6% were rat positive. These findings and the absence of M. tuberculosis-specific volatiles in nonmycobacterial species indicate that rats can be trained to specifically detect M. tuberculosis.
Mgode, G. F., Weetjens, B. J., Nawrath, T., Cox, C., Jubitana, M., Machang'u, R. S., Cohen-Bacrie, S., Bedotto, M., Drancourt, M., Schulz, S., Kaufmann, S. H. E.
Diagnosis of Tuberculosis by Trained African Giant Pouched Rats and Confounding Impact of Pathogens and Microflora of the Respiratory Tract [Mycobacteriology and Aerobic Actinomycetes]
Date de mise en ligne : Vendredi 20 janvier 2012 The use of telaprevir and boceprevir, both protease inhibitors (PI), as part of the specifically targeted antiviral therapy for hepatitis C (STAT-C) has significantly improved sustained virologic response (SVR) rates. However, different clinical studies have also identified several mutations associated with viral resistance to both PIs. In the absence of selective pressure, drug-resistant hepatitis C virus (HCV) mutants are generally present at low frequency, making mutation detection challenging. Here, we describe a mismatch amplification mutation assay (MAMA) PCR method for the specific detection of naturally occurring drug-resistant HCV mutants. MAMA PCR successfully identified the corresponding HCV variants, while conventional methods such as direct sequencing, endpoint limiting dilution (EPLD), and bacterial cloning were not sensitive enough to detect circulating drug-resistant mutants in clinical specimens. Ultradeep pyrosequencing was used to confirm the presence of the corresponding HCV mutants. In treatment-naïve patients, the frequency of all resistant variants was below 1%. Deep amplicon sequencing allowed a detailed analysis of the structure of the viral population among these patients, showing that the evolution of the NS3 is limited to a rather small sequence space. Monitoring of HCV drug resistance before and during treatment is likely to provide important information for management of patients undergoing anti-HCV therapy.
Fonseca-Coronado, S., Escobar-Gutierrez, A., Ruiz-Tovar, K., Cruz-Rivera, M. Y., Rivera-Osorio, P., Vazquez-Pichardo, M., Carpio-Pedroza, J. C., Ruiz-Pacheco, J. A., Cazares, F., Vaughan, G.
Specific Detection of Naturally Occurring Hepatitis C Virus Mutants with Resistance to Telaprevir and Boceprevir (Protease Inhibitors) among Treatment-Naive Infected Individuals [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Hand, foot, and mouth disease (HFMD) is a contagious enteroviral disease occurring primarily in young children and caused by enterovirus 71 (EV71), coxsackievirus A16 (CVA16), and other serotypes of coxsackievirus and echovirus. In this study, a GeXP analyzer-based multiplex reverse transcription (RT)-PCR assay (GeXP assay) consisting of chimeric primer-based PCR amplification with fluorescent labeling and capillary electrophoresis separation was developed to simultaneously identify nine serotypes of enteroviruses associated with HFMD in China, including EV71, CVA16, CVA4, -5, -9, and -10, and CVB1, -3, and -5. The RNAs extracted from cell cultures of viral isolates and synthetic RNAs via in vitro transcription were used to analyze the specificity and sensitivity of the assay. The GeXP assay detected as little as 0.03 tissue culture infective dose (TCID50) of EV71 and CVA16, 10 copies of panenterovirus, EV71, CVA16, CVB1, and CVB5, and 100 copies of 10 (including panenterovirus) premixed RNA templates. A total of 180 stool specimens collected from HFMD patients and persons suspected of having HFMD were used to evaluate the clinical performance of this assay. In comparison with the results of conventional methods, the sensitivities of the GeXP assay for detection of panenterovirus, EV71, and CVA16 were 98.79% (163/165), 91.67% (44/48), and 91.67% (33/36), respectively, and the specificities were 80.00% (12/15), 98.48% (130/132), and 100% (144/144), respectively. The concordance of typing seven other serotypes of enteroviruses with the results of conventional methods was 92.59% (25/27). In conclusion, the GeXP assay is a rapid, cost-effective, and high-throughput method for typing nine serotypes of HFMD-associated enteroviruses.
Hu, X., Zhang, Y., Zhou, X., Xu, B., Yang, M., Wang, M., Zhang, C., Li, J., Bai, R., Xu, W., Ma, X.
Simultaneously Typing Nine Serotypes of Enteroviruses Associated with Hand, Foot, and Mouth Disease by a GeXP Analyzer-Based Multiplex Reverse Transcription-PCR Assay [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 A study was designed to assess the importance of sequence types among extended-spectrum β-lactamase (ESBL)-producing Escherichia coli isolates causing bacteremia over an 11-year period (2000 to 2010) in a centralized Canadian region. A total of 197 patients with incident infections were identified; the majority presented with community-onset urosepsis, with a significant increase in the prevalence of ESBL-producing E. coli during the later part of the study. The majority of E. coli isolates produced either CTX-M-15 or CTX-M-14. We identified 7 different major sequence types among 91% of isolates (i.e., the ST10 clonal complex, ST38, ST131, ST315, ST393, ST405, and ST648) and provided insight into their clinical and molecular characteristics. ST38 was the most antimicrobial-susceptible sequence type and predominated during 2000 to 2004 but disappeared after 2008. ST131 was the most antimicrobial-resistant sequence type, and the influx of a single pulsotype of this sequence type was responsible for the significant increase of ESBL-producing E. coli strains since 2007. During 2010, 49/63 (78%) of the ESBL-producing E. coli isolates belonged to ST131, and this sequence type had established itself as a major drug-resistant pathogen in Calgary, Alberta, Canada, posing an important new public health threat within our region. We urgently need well-designed epidemiological and molecular studies to understand the dynamics of transmission, risk factors, and reservoirs for E. coli ST131. This will provide insight into the emergence and spread of this multiresistant sequence type.
Peirano, G., van der Bij, A. K., Gregson, D. B., Pitout, J. D. D.
Molecular Epidemiology over an 11-Year Period (2000 to 2010) of Extended-Spectrum {beta}-Lactamase-Producing Escherichia coli Causing Bacteremia in a Centralized Canadian Region [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 High-risk human papillomavirus (HR-HPV) testing is increasingly important. We therefore examined the impact on accuracy of repeated versus one-time testing, type-specific versus pooled detection, and assay analytic sensitivity. By using a nested case-control design from the ASCUS-LSIL Triage Study, we selected women with incident cervical intraepithelial neoplasia grade 2 or grade 3 (CIN2/3; n = 325) and a random sample of women with
Marks, M. A., Castle, P. E., Schiffman, M., Gravitt, P. E.
Evaluation of Any or Type-Specific Persistence of High-Risk Human Papillomavirus for Detecting Cervical Precancer [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 Leptospirosis is one of the most widespread zoonoses in the world. However, there is a lack of information on circulating Leptospira strains in remote parts of the world. We describe the serological and molecular features of leptospires isolated from 94 leptospirosis patients in Mayotte, a French department located in the Comoros archipelago, between 2007 and 2010. Multilocus sequence typing identified these isolates as Leptospira interrogans, L. kirschneri, L. borgpetersenii, and members of a previously undefined phylogenetic group. This group, consisting of 15 strains, could represent a novel species. Serological typing revealed that 70% of the isolates belonged to the serogroup complex Mini/Sejroe/Hebdomadis, followed by the serogroups Pyrogenes, Grippotyphosa, and Pomona. However, unambiguous typing at the serovar level was not possible for most of the strains because the isolate could belong to more than one serovar or because serovar and species did not match the original classification. Our results indicate that the serovar and genotype distribution in Mayotte differs from what is observed in other regions, thus suggesting a high degree of diversity of circulating isolates worldwide. These results are essential for the improvement of current diagnostic tools and provide a starting point for a better understanding of the epidemiology of leptospirosis in this area of endemicity.
Bourhy, P., Collet, L., Lernout, T., Zinini, F., Hartskeerl, R. A., van der Linden, H., Thiberge, J. M., Diancourt, L., Brisse, S., Giry, C., Pettinelli, F., Picardeau, M.
Human Leptospira Isolates Circulating in Mayotte (Indian Ocean) Have Unique Serological and Molecular Features [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 Limited clinical information is available regarding community onset infections caused by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli. A case-control study was performed to evaluate the epidemiology and risk factors of these types of infections. A case patient was defined as a person whose clinical sample yielded ESBL-producing E. coli. For each case patient, one control was randomly chosen from a group of outpatients from whom non-ESBL-producing E. coli had been isolated and for whom a clinical sample had been sent to the same laboratory for culturing during the following week. Of 108 cases of ESBL-producing E. coli, 56 (51.9%) were classified as health care associated (HCA). Univariate analysis showed male gender, HCA infection, severe underlying illness, and a prior receipt of antibiotics to be associated with ESBL-producing E. coli. In the multivariate analysis, HCA infection (odds ratio [OR], 3.18; 95% confidence interval [CI], 1.67 to 6.06; P < 0.001) and previous use of antibiotics (OR, 4.88; 95% CI, 2.08 to 11.48; P < 0.001) were found to be significantly associated with the ESBL group. In a multivariate analysis that included each antibiotic, previous use of fluoroquinolone (OR, 7.32; 95% CI, 1.58 to 34.01; P = 0.011) was significantly associated with ESBL-producing E. coli. Of 101 isolates in which ESBLs and their molecular relationships were studied, all isolates produced ESBLs from the CTX-M family (CTX-M-14, 40 isolates; CTX-M-15, 39 isolates; and other members of the CTX-M family, 22 isolates). In conclusion, this study confirms that ESBL-producing E. coli strains are a notable cause of community onset infections in predisposed patients. HCA infection and previous use of fluoroquinolone were significant factors associated with ESBL-producing E. coli in community onset infections.
Kang, C.-I., Wi, Y. M., Lee, M. Y., Ko, K. S., Chung, D. R., Peck, K. R., Lee, N. Y., Song, J.-H.
Epidemiology and Risk Factors of Community Onset Infections Caused by Extended-Spectrum {beta}-Lactamase-Producing Escherichia coli Strains [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 This study investigated "creep" in vancomycin and daptomycin MICs among methicillin-resistant Staphylococcus aureus (MRSA) isolates from blood cultures over a 5-year period in a hospital in the United Kingdom, using different susceptibility testing methods. Trends in vancomycin and daptomycin susceptibility were evaluated by using Etest performed prospectively on isolates in routine clinical practice from December 2007 to December 2010 (n = 102). Comparison was made to results from prospective testing of subcultures at the Scottish MRSA Reference Laboratory, using an automated system (Vitek 2) and retrospective testing (Etest and CLSI reference broth microdilution [BMD] method) of stored isolates from 2006 to 2010 (n = 208). Spearman's rank correlations revealed a significant increase in vancomycin MIC (P = 0.012) and a significant decrease in daptomycin MIC (P = 0.03) by year of study for Etest results from the time of isolation. However, neither trend was replicated in MICs from automated or retrospective testing. The Friedman test revealed a significant difference between vancomycin MICs obtained from the same samples by different testing methods (2 [3 degrees of freedom] = 97; P < 0.001). MICs from automated testing and Etest analysis of stored isolates were significantly lower than those from Etest analysis at the time of isolation for both antibiotics (P < 0.001). Effects of storage on the MIC appeared within the first 6 months of storage. Inconsistent evidence on vancomycin MIC creep and the relevance of the MIC to clinical outcome may arise from differences in susceptibility testing methods, including storage of isolates. There is a need to standardize and streamline susceptibility testing of vancomycin against MRSA.
Edwards, B., Milne, K., Lawes, T., Cook, I., Robb, A., Gould, I. M.
Is Vancomycin MIC "Creep" Method Dependent? Analysis of Methicillin-Resistant Staphylococcus aureus Susceptibility Trends in Blood Isolates from North East Scotland from 2006 to 2010 [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 Tuberculosis (TB) remains a significant global health problem for which rapid diagnosis is critical to both treatment and control. This report describes a multiplex PCR method, the Mycobacterial IDentification and Drug Resistance Screen (MID-DRS) assay, which allows identification of members of the Mycobacterium tuberculosis complex (MTBC) and the simultaneous amplification of targets for sequencing-based drug resistance screening of rifampin-resistant (rifampinr), isoniazidr, and pyrazinamider TB. Additionally, the same multiplex reaction amplifies a specific 16S rRNA gene target for rapid identification of M. avium complex (MAC) and a region of the heat shock protein 65 gene (hsp65) for further DNA sequencing-based confirmation or identification of other mycobacterial species. Comparison of preliminary results generated with MID-DRS versus culture-based methods for a total of 188 bacterial isolates demonstrated MID-DRS sensitivity and specificity as 100% and 96.8% for MTBC identification; 100% and 98.3% for MAC identification; 97.4% and 98.7% for rifampinr TB identification; 60.6% and 100% for isoniazidr TB identification; and 75.0% and 98.1% for pyrazinamider TB identification. The performance of the MID-DRS was also tested on acid-fast-bacterium (AFB)-positive clinical specimens, resulting in sensitivity and specificity of 100% and 78.6% for detection of MTBC and 100% and 97.8% for detection of MAC. In conclusion, use of the MID-DRS reduces the time necessary for initial identification and drug resistance screening of TB specimens to as little as 2 days. Since all targets needed for completing the assay are included in a single PCR amplification step, assay costs, preparation time, and risks due to user errors are also reduced.
Perez-Osorio, A. C., Boyle, D. S., Ingham, Z. K., Ostash, A., Gautom, R. K., Colombel, C., Houze, Y., Leader, B. T.
Rapid Identification of Mycobacteria and Drug-Resistant Mycobacterium tuberculosis by Use of a Single Multiplex PCR and DNA Sequencing [Mycobacteriology and Aerobic Actinomycetes]
Date de mise en ligne : Vendredi 20 janvier 2012 While viral load testing has gained widespread acceptance, a primary limitation remains the variability of results, particularly between different laboratories. While some work has demonstrated the importance of standardized quantitative control material in reducing this variability, little has been done to explore other important factors in the molecular amplification process. Results of 185 laboratories enrolled in the College of American Pathologists (CAP) 2009 viral load proficiency testing (PT) survey (VLS) were examined. This included 165 labs (89.2%) testing for cytomegalovirus (CMV), 99 (53.5%) for Epstein-Barr virus (EBV), and 64 (34.6%) for BK virus (BKV). At the time of PT, laboratories were asked a series of questions to characterize their testing methods. The responses to these questions were correlated to mean viral load (MVL) and result variability (RV). Contribution of individual factors to RV was estimated through analysis of variance (ANOVA) modeling and the use of backward selection of factors to fit those models. Selection of the quantitative calibrator, commercially prepared primers and probes, and amplification target gene were found most prominently associated with changes in MVL or RV for one or more of the viruses studied. Commercially prepared primers and probes and amplification target gene made the largest contribution to overall variability. Factors contributing to MVL and RV differed among viruses, as did relative contribution of each factor to overall variability. The marked variability seen in clinical quantitative viral load results is associated with multiple aspects of molecular testing design and performance. The reduction of such variability will require a multifaceted approach to improve the accuracy, reliability, and clinical utility of these important tests.
Hayden, R. T., Yan, X., Wick, M. T., Rodriguez, A. B., Xiong, X., Ginocchio, C. C., Mitchell, M. J., Caliendo, A. M., for the College of American Pathologists Microbiology Resource Committee
Factors Contributing to Variability of Quantitative Viral PCR Results in Proficiency Testing Samples: a Multivariate Analysis [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Bloodstream infections are a leading cause of admissions to hospital intensive care units and carry a high mortality rate. Clinical outcome can be greatly improved by early effective antibiotic therapy; therefore, broad-spectrum antimicrobial therapy is often initiated when there is a clinical suspicion of bloodstream infection. Unfortunately, this method may not always be effective when dealing with inherently resistant organisms and can also result in iatrogenic infection and the development of resistant isolates. Rapid identification of the infecting organism may aid in choosing appropriate antimicrobial therapy, thereby reducing these potential adverse events. We compared the matrix-assisted laser desorption ionization (MALDI) Biotyper system with Sepsityper specimen processing (Bruker Daltonics, Billerica, MA) to routine methods for the identification of microorganisms from 164 positive blood cultures. The MALDI Biotyper/Sepsityper identified 85.5% of bacterial isolates directly from positive monomicrobial blood cultures with 97.6% concordance to genus and 94.1% concordance to species with routine identification methods. Gram-negative isolates were more likely to produce acceptable confidence scores (97.8%) than Gram-positive isolates (80.0%); however, genus and species concordance with routine identification methods were similar in both groups. Reanalysis of collected spectra using modified blood culture-specific parameters resulted in an improved overall identification rate for Gram-positive bacteria (89.0%). Median times to identification using the MALDI Biotyper/Sepsityper were 23 to 83 h faster than routine methods for Gram-positive isolates and 34 to 51 h faster for Gram-negative isolates.
Buchan, B. W., Riebe, K. M., Ledeboer, N. A.
Comparison of the MALDI Biotyper System Using Sepsityper Specimen Processing to Routine Microbiological Methods for Identification of Bacteria from Positive Blood Culture Bottles [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 In China, rubella vaccination was introduced into the national immunization program in 2008, and a rubella epidemic occurred in the same year. In order to know whether changes in the genotypic distribution of rubella viruses have occurred in the postvaccination era, we investigate in detail the epidemiological profile of rubella in China and estimate the evolutionary rate, molecular clock phylogeny, and demographic history of the predominant rubella virus genotypes circulating in China using Bayesian Markov chain Monte Carlo phylodynamic analyses. 1E was found to be the predominant rubella virus genotype since its initial isolation in China in 2001, and no genotypic shift has occurred since then. The results suggest that the global 1E genotype may have diverged in 1995 and that it has evolved at a mutation rate of 1.65 x 10–3 per site per year. The Chinese 1E rubella virus isolates were grouped into either cluster 1 or cluster 2, which likely originated in 1997 and 2006, respectively. Cluster 1 viruses were found in all provinces examined in this study and had a mutation rate of 1.90 x 10–3 per site per year. The effective number of infections remained constant until 2007, and along with the introduction of rubella vaccine into the national immunization program, although the circulation of cluster 1 viruses has not been interrupted, some viral lineages have disappeared, and the epidemic started a decline that led to a decrease in the effective population size. Cluster 2 viruses were found only in Hainan Province, likely because of importation.
Zhu, Z., Cui, A., Wang, H., Zhang, Y., Liu, C., Wang, C., Zhou, S., Chen, X., Zhang, Z., Feng, D., Wang, Y., Chen, H., Pan, Z., Zeng, X., Zhou, J., Wang, S., Chang, X., Lei, Y., Tian, H., Liu, Y., Zhou, S., Zhan, J., Chen, H., Gu, S., Tian, X., Liu, J., Chen, Y., Fu, H., Yang, X., Zheng, H., Liu, L., Zheng, L., Gao, H., He, J., Sun, L., Xu, W.
Emergence and Continuous Evolution of Genotype 1E Rubella Viruses in China [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 The FilmArray Respiratory Panel (RP) multiplexed nucleic acid amplification test (Idaho Technology, Inc., Salt Lake City, UT) was compared to laboratory-developed real-time PCR assays for the detection of various respiratory viruses and certain bacterial pathogens. A total of 215 frozen archived pediatric respiratory specimens previously characterized as either negative or positive for one or more pathogens by real-time PCR were examined using the FilmArray RP system. Overall agreement between the FilmArray RP and corresponding real-time PCR assays for shared analytes was 98.6% (kappa = 0.92 [95% confidence interval (CI), 0.89 to 0.94]). The combined positive percent agreement was 89.4% (95% CI, 85.4 to 92.6); the negative percent agreement was 99.6% (95% CI, 99.2 to 99.8). The mean real-time PCR threshold cycle (CT) value for specimens with discordant results was 36.46 ± 4.54. Detection of coinfections and correct identification of influenza A virus subtypes were comparable to those of real-time PCR when using the FilmArray RP. The greatest comparative difference in sensitivity was observed for adenovirus; only 11 of 24 (45.8%; 95% CI, 27.9 to 64.9) clinical specimens positive for adenovirus by real-time PCR were also positive by the FilmArray RP. In addition, upon testing 20 characterized adenovirus serotypes prepared at high and low viral loads, the FilmArray RP did not detect serotypes 6 and 41 at either level and failed to detect serotypes 2, 20, 35, and 37 when viral loads were low. The FilmArray RP system is rapid and extremely user-friendly, with results available in just over 1 h with almost no labor involved. Its low throughput is a significant drawback for laboratories receiving large numbers of specimens, as only a single sample can be processed at a time with one instrument.
Pierce, V. M., Elkan, M., Leet, M., McGowan, K. L., Hodinka, R. L.
Comparison of the Idaho Technology FilmArray System to Real-Time PCR for Detection of Respiratory Pathogens in Children [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 The recent emergence of the human infection confirmed to be caused by severe fever with thrombocytopenia syndrome virus (SFTSV) in China is of global concern. Safe diagnostic immunoreagents for determination of human and animal seroprevalence in epidemiological investigations are urgently needed. This paper describes the cloning and expression of the nucleocapsid (N) protein of SFTSV. An N-protein-based double-antigen sandwich enzyme-linked immunosorbent assay (ELISA) system was set up to detect the total antibodies in human and animal sera. We reasoned that as the double-antigen sandwich ELISA detected total antibodies with a higher sensitivity than traditional indirect ELISA, it could be used to detect SFTSV-specific antibodies from different animal species. The serum neutralization test was used to validate the performance of this ELISA system. All human and animal sera that tested positive in the neutralization test were also positive in the sandwich ELISA, and there was a high correlation between serum neutralizing titers and ELISA readings. Cross-reactivity was evaluated, and the system was found to be highly specific to SFTSV; all hantavirus- and dengue virus-confirmed patient samples were negative. SFTSV-confirmed human and animal sera from both Anhui and Hubei Provinces in China reacted with N protein in this ELISA, suggesting no major antigenic variation between geographically disparate virus isolates and the suitability of this assay in nationwide application. ELISA results showed that 3.6% of the human serum samples and 47.7% of the animal field serum samples were positive for SFTSV antibodies, indicating that SFTSV has circulated widely in China. This assay, which is simple to operate, poses no biohazard risk, does not require sophisticated equipment, and can be used in disease surveillance programs, particularly in the screening of large numbers of samples from various animal species.
Jiao, Y., Zeng, X., Guo, X., Qi, X., Zhang, X., Shi, Z., Zhou, M., Bao, C., Zhang, W., Xu, Y., Wang, H.
Preparation and Evaluation of Recombinant Severe Fever with Thrombocytopenia Syndrome Virus Nucleocapsid Protein for Detection of Total Antibodies in Human and Animal Sera by Double-Antigen Sandwich Enzyme-Linked Immunosorbent Assay [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Newcastle disease (ND) is one of the most important diseases of poultry, negatively affecting poultry production worldwide. The disease is caused by Newcastle disease virus (NDV) or avian paramyxovirus type 1 (APMV-1), a negative-sense single-stranded RNA virus of the genus Avulavirus, family Paramyxoviridae. Although all NDV isolates characterized to date belong to a single serotype of APMV-1, significant genetic diversity has been described between different NDV isolates. Here we present the complete genome sequence and the clinicopathological characterization of a virulent Newcastle disease virus isolate (NDV-Peru/08) obtained from poultry during an outbreak of ND in Peru in 2008. Phylogenetic reconstruction and analysis of the evolutionary distances between NDV-Peru/08 and other isolates representing established NDV genotypes revealed the existence of large genomic and amino differences that clearly distinguish this isolate from viruses of typical NDV genotypes. Although NDV-Peru/08 is a genetically distinct virus, pathogenesis studies conducted with chickens revealed that NDV-Peru/08 infection results in clinical signs characteristic of velogenic viscerotropic NDV strains. Additionally, vaccination studies have shown that an inactivated NDV-LaSota/46 vaccine conferred full protection from NDV-Peru/08-induced clinical disease and mortality. This represents the first complete characterization of a virulent NDV isolate from South America.
Diel, D. G., Susta, L., Cardenas Garcia, S., Killian, M. L., Brown, C. C., Miller, P. J., Afonso, C. L.
Complete Genome and Clinicopathological Characterization of a Virulent Newcastle Disease Virus Isolate from South America [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Immigrants from high-burden countries and HIV-coinfected individuals are risk groups for tuberculosis (TB) in countries with low TB incidence. Therefore, we studied their role in transmission of Mycobacterium tuberculosis in Switzerland. We included all TB patients from the Swiss HIV Cohort and a sample of patients from the national TB registry. We identified molecular clusters by spoligotyping and mycobacterial interspersed repetitive-unit–variable-number tandem-repeat (MIRU-VNTR) analysis and used weighted logistic regression adjusted for age and sex to identify risk factors for clustering, taking sampling proportions into account. In total, we analyzed 520 TB cases diagnosed between 2000 and 2008; 401 were foreign born, and 113 were HIV coinfected. The Euro-American M. tuberculosis lineage dominated throughout the study period (378 strains; 72.7%), with no evidence for another lineage, such as the Beijing genotype, emerging. We identified 35 molecular clusters with 90 patients, indicating recent transmission; 31 clusters involved foreign-born patients, and 15 involved HIV-infected patients. Birth origin was not associated with clustering (adjusted odds ratio [aOR], 1.58; 95% confidence interval [CI], 0.73 to 3.43; P = 0.25, comparing Swiss-born with foreign-born patients), but clustering was reduced in HIV-infected patients (aOR, 0.49; 95% CI, 0.26 to 0.93; P = 0.030). Cavitary disease, male sex, and younger age were all associated with molecular clustering. In conclusion, most TB patients in Switzerland were foreign born, but transmission of M. tuberculosis was not more common among immigrants and was reduced in HIV-infected patients followed up in the national HIV cohort study. Continued access to health services and clinical follow-up will be essential to control TB in this population.
Fenner, L., Gagneux, S., Helbling, P., Battegay, M., Rieder, H. L., Pfyffer, G. E., Zwahlen, M., Furrer, H., Siegrist, H. H., Fehr, J., Dolina, M., Calmy, A., Stucki, D., Jaton, K., Janssens, J.-P., Stalder, J. M., Bodmer, T., Ninet, B., Bottger, E. C., Egger, M., for the Swiss HIV Cohort and Molecular Epidemiology of Tuberculosis Study Groups
Mycobacterium tuberculosis Transmission in a Country with Low Tuberculosis Incidence: Role of Immigration and HIV Infection [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 The recent association of certain influenza A virus subtypes with clinically relevant phenotypes has led to the increasing importance of subtyping by clinical virology laboratories. To provide clinical laboratories with a definitive immunofluorescence assay for the subtyping of influenza A virus isolates, we generated a panel of monoclonal antibodies (MAbs) against the major circulating influenza A virus subtypes using multiple inactivated H1N1, H3N2, and 2009 H1N1 strains individually as immunogens. Eleven MAbs that target hemagglutinin (HA) of H1N1 and H3N2 subtypes were selected. These MAbs were combined into three subtype-specific reagents, one each for pan-H1 (seasonal and 2009 strains), H3, and 2009 H1, for the subtyping of influenza A virus-positive specimens by indirect immunofluorescence assay (IFA). Each subtype-specific reagent was tested on 21 prototype influenza A virus strains and confirmed to be specific for its intended subtype. In addition, the subtyping reagents did not cross-react with any of 40 other viruses. The clinical performance of the subtyping reagents was evaluated with 75 archived clinical samples collected between 2006 and 2009 using the D3 Ultra DFA influenza A virus identification reagent (Diagnostic Hybrids, Inc., Athens, OH) and the influenza A virus subtyping reagents by IFA simultaneously. Sixty-four samples grew virus and were subtyped as follows: 30 as H3N2, 9 as seasonal H1N1, and 25 as 2009 H1N1. RT-PCR was used to confirm the influenza A virus subtyping of these samples, and there was 100% agreement with IFA. This subtyping IFA provides clinical laboratories with a cost-effective diagnostic tool for better management of influenza virus infection and surveillance of influenza virus activity.
Johnson, J., Higgins, A., Navarro, A., Huang, Y., Esper, F. L., Barton, N., Esch, D., Shaw, C., Olivo, P. D., Miao, L. Y.
Subtyping Influenza A Virus with Monoclonal Antibodies and an Indirect Immunofluorescence Assay [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Liquid-based urine cytology (LB-URC) was evaluated for cytological diagnosis and detection of human papillomavirus (HPV), Mycoplasma, and Ureaplasma. Midstream urine samples were collected from 141 male patients with urethritis and 154 controls without urethritis, and sediment cells were preserved in liquid-based cytology solution. Urethral swabs from urethritis patients were tested for the presence of Neisseria gonorrhoeae and Chlamydia trachomatis. Papanicolaou tests were performed for cytological evaluation. HPV, Mycoplasma, and Ureaplasma genomes were determined by PCR-based methods, and localization of HPV DNA in urothelial cells was examined by in situ hybridization (ISH). The β-globin gene was positive in 97.9% of LB-URC samples from urethritis patients and in 97.4% of control samples, suggesting that high-quality cellular DNA was obtained from the LB-URC samples. HPV DNA was detected in 29 (21.0%) urethritis cases and in five (3.3%) controls (P < 0.05). HPV type 16 (HPV 16) was most commonly found in urethritis patients. Cytological evaluations could be performed for 92.1% of urethritis patients and 64.3% of controls. Morphological changes suggestive of HPV infection were seen in 20.7% of the HPV-positive samples, and ISH demonstrated the presence of HPV DNA in both squamous and urothelial cells in HPV-positive samples. Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum were detected in 14.5%, 10.9%, 6.5%, and 12.3% of urethritis patients, respectively. The prevalence rates of these microorganisms (except Ureaplasma parvum) were significantly higher in urethritis cases than controls (P < 0.05). LB-URC is applicable for detection of HPV, Mycoplasma, and Ureaplasma. HPV infection occurs in urothelial cells, especially in gonococcal urethritis.
Kawaguchi, S., Shigehara, K., Sasagawa, T., Shimamura, M., Nakashima, T., Sugimoto, K., Nakashima, K., Furubayashi, K., Namiki, M.
Liquid-Based Urine Cytology as a Tool for Detection of Human Papillomavirus, Mycoplasma spp., and Ureaplasma spp. in Men [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 HIV-1 group M is classified into 9 subtypes, as well as recombinants favored by coinfection and superinfection events with different variants. Although HIV-1 subtype B is predominant in Europe, intersubtype recombinants are increasing in prevalence and complexity. In this study, phylogenetic analyses of pol sequences were performed to detect the HIV-1 circulating and unique recombinant forms (CRFs and URFs, respectively) in a Spanish cohort of antiretroviral treatment-naïve HIV-infected patients included in the Research Network on HIV/AIDS (CoRIS). Bootscanning and other methods were used to define complex recombinants not assigned to any subtype or CRF. A total of 670 available HIV-1 pol sequences from different patients were collected, of which 588 (87.8%) were assigned to HIV-1 subtype B and 82 (12.2%) to HIV-1 non-B variants. Recombinants caused the majority (71.9%) of HIV-1 non-B infections and were found in 8.8% of CoRIS patients. Eleven URFs (accounting for 13.4% of HIV-1 non-B infections), presenting complex mosaic patterns, were detected. Among them, 10 harbored subtype B fragments. Four of the 11 URFs were found in Spanish natives. A cluster of three B/CRF02_AG recombinants was detected. We conclude that complex variants, including unique recombinant forms, are being introduced into Spain through both immigrants and natives. An increase in the frequency of mosaic viruses, reflecting the increasing heterogeneity of the HIV epidemic in our country, is expected.
Yebra, G., de Mulder, M., Martin, L., Rodriguez, C., Labarga, P., Viciana, I., Berenguer, J., Aleman, M. R., Pineda, J. A., Garcia, F., Holguin, A., Cohort of the Spanish AIDS Research Network (CoRIS)
Most HIV Type 1 Non-B Infections in the Spanish Cohort of Antiretroviral Treatment-Naive HIV-Infected Patients (CoRIS) Are Due to Recombinant Viruses [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 This retrospective study included 10 eyes of 9 patients diagnosed with microsporidial keratitis. All of them were known to contract this disease after taking baths in hot springs. The disease was diagnosed based on detecting microsporidia in corneal scrapings using Gram stain and the modified Kinyoun's acid-fast stain. The specimens from the last six patients were subjected to PCR and then sequencing. All of them revealed that the microorganism identified has a high similarity to Vittaforma corneae. Repeated debridement of the epithelial lesions successfully eradicated the microsporidial infection in all nine patients.
Fan, N.-W., Wu, C.-C., Chen, T.-L., Yu, W.-K., Chen, C.-P., Lee, S.-M., Lin, P.-Y.
Microsporidial Keratitis in Patients with Hot Springs Exposure [Parasitology]
Date de mise en ligne : Vendredi 20 janvier 2012 Zygomycetes of the order Mucorales can cause life-threatening infections in humans. These mucormycoses are emerging and associated with a rapid tissue destruction and high mortality. The resistance of Mucorales to antimycotic substances varies between and within clinically important genera such as Mucor, Rhizopus, and Lichtheimia. Thus, an accurate diagnosis before onset of antimycotic therapy is recommended. Matrix-assisted laser desorption ionization (MALDI)–time of flight (TOF) mass spectrometry (MS) is a potentially powerful tool to rapidly identify infectious agents on the species level. We investigated the potential of MALDI-TOF MS to differentiate Lichtheimia species, one of the most important agents of mucormycoses. Using the Bruker Daltonics FlexAnalysis (version 3.0) software package, a spectral database library with m/z ratios of 2,000 to 20,000 Da was created for 19 type and reference strains of clinically relevant Zygomycetes of the order Mucorales (12 species in 7 genera). The database was tested for accuracy by use of 34 clinical and environmental isolates of Lichtheimia comprising a total of five species. Our data demonstrate that MALDI-TOF MS can be used to clearly discriminate Lichtheimia species from other pathogenic species of the Mucorales. Furthermore, the method is suitable to discriminate species within the genus. The reliability and robustness of the MALDI-TOF-based identification are evidenced by high score values (above 2.3) for the designation to a certain species and by moderate score values (below 2.0) for the discrimination between clinically relevant (Lichtheimia corymbifera, L. ramosa, and L. ornata) and irrelevant (L. hyalospora and L. sphaerocystis) species. In total, all 34 strains were unequivocally identified by MALDI-TOF MS with score values of >1.8 down to the generic level, 32 out of 34 of the Lichtheimia isolates (except CNM-CM 5399 and FSU 10566) were identified accurately with score values of >2 (probable species identification), and 25 of 34 isolates were identified to the species level with score values of >2.3 (highly probable species identification). The MALDI-TOF MS-based method reported here was found to be reproducible and accurate, with low consumable costs and minimal preparation time.
Schrodl, W., Heydel, T., Schwartze, V. U., Hoffmann, K., Grosse-Herrenthey, A., Walther, G., Alastruey-Izquierdo, A., Rodriguez-Tudela, J. L., Olias, P., Jacobsen, I. D., de Hoog, G. S., Voigt, K.
Direct Analysis and Identification of Pathogenic Lichtheimia Species by Matrix-Assisted Laser Desorption Ionization-Time of Flight Analyzer-Mediated Mass Spectrometry [Mycology]
Date de mise en ligne : Vendredi 20 janvier 2012 Pyrazinamide is important in the treatment of tuberculosis. Unfortunately, the diagnosis of pyrazinamide resistance is hampered by technical difficulties. We hypothesized that mutation analysis combined with the mycobacterial growth indicator tube (MGIT) phenotypic method would be a good predictor of pyrazinamide resistance. We prospectively analyzed 1,650 M. tuberculosis isolates referred to our tuberculosis reference laboratory in 2008 and 2009. In our laboratory, the MGIT 960 system was used for pyrazinamide resistance screening. If a pyrazinamide-resistant strain was detected, we performed a pncA gene mutation analysis. A second MGIT 960 susceptibility assay was performed afterwards to evaluate the accuracy of the pncA mutation analysis to detect true- or false-positive MGIT results. We observed pyrazinamide resistance in 69 samples using the first MGIT 960 analysis. In a second MGIT 960 analysis, 47 of the 69 samples proved susceptible (68% false positivity). Sensitivity of nonsynonymous pncA mutations for detecting resistant isolates was 73% (95% confidence interval [CI], 61% to 73%), and specificity was 100% (95% CI, 95% to 100%). A diagnostic algorithm incorporating phenotypic and molecular methods would have a 100% positive predictive value for detecting pyrazinamide-resistant isolates, indicating that such an algorithm, based on both methods, is a good predictor for pyrazinamide resistance in routine diagnostics.
Simons, S. O., van Ingen, J., van der Laan, T., Mulder, A., Dekhuijzen, P. N. R., Boeree, M. J., van Soolingen, D.
Validation of pncA Gene Sequencing in Combination with the Mycobacterial Growth Indicator Tube Method To Test Susceptibility of Mycobacterium tuberculosis to Pyrazinamide [Mycobacteriology and Aerobic Actinomycetes]
Date de mise en ligne : Vendredi 20 janvier 2012 Conventional indirect drug susceptibility testing of Mycobacterium tuberculosis with liquid medium is well established and offers time-saving and reliable results. This multicenter study was carried out to evaluate if drug susceptibility testing (DST) can be successfully carried out directly from processed smear-positive specimens (direct DST) and if this approach could offer substantial time savings. Sputum specimens were digested, decontaminated, and concentrated by the laboratory routine procedure and were inoculated in Bactec MGIT 960 as well as Lowenstein-Jensen (LJ) medium for primary isolation. All the processed specimens which were acid-fast bacterium (AFB) smear positive were used for setting up direct DST for isoniazid (INH) and rifampin (RIF). After the antimicrobial mixture of polymyxin B, amphotericin B, nalidixic acid, trimethoprim, and azlocillin (PANTA) was added, the tubes were entered in the MGIT 960 instrument using the 21-day protocol (Bactec 960 pyrazinamide [PZA] protocol). Results obtained by direct DST were compared with those obtained by indirect DST to establish accuracy and time savings by this approach. Of a total of 360 AFB smear-positive sputum specimens set up for direct DST at four sites in three different countries, 307 (85%) specimens yielded reportable results. Average reporting time for direct DST was 11 days (range, 10 to 12 days). The average time savings by direct DST compared to indirect DST, which included time to isolate a culture and perform DST, was 8 days (range, 6 to 9 days). When results of direct DST were compared with those of indirect DST, there was 95.1% concordance with INH and 96.1% with rifampin. These findings indicate that direct DST with the Bactec MGIT 960 system offers further time savings and is a quick method to reliably detect multidrug resistance (MDR) cases.
Siddiqi, S., Ahmed, A., Asif, S., Behera, D., Javaid, M., Jani, J., Jyoti, A., Mahatre, R., Mahto, D., Richter, E., Rodrigues, C., Visalakshi, P., Rusch-Gerdes, S.
Direct Drug Susceptibility Testing of Mycobacterium tuberculosis for Rapid Detection of Multidrug Resistance Using the Bactec MGIT 960 System: a Multicenter Study [Mycobacteriology and Aerobic Actinomycetes]
Date de mise en ligne : Vendredi 20 janvier 2012 The plasticity region of Helicobacter pylori is a large chromosomal segment including isolate-specific open reading frames with characteristics of pathogenicity islands. It remains unclear whether genes in the plasticity region play a role in the pathogenesis of gastric mucosal inflammation and gastroduodenal disease. Our aim was to assess the role of selected genes in the plasticity region in relation to risk of H. pylori-related disease and the severity of gastric mucosal damage. We used PCR to study the relation of disease outcome and mucosal damage with four genes in the H. pylori plasticity region (jhp0940, jhp0945, jhp0947, and jhp0949) from isolates obtained from both Western (n = 296) and East Asian (n = 217) patients. The prevalence of jhp0945, jhp0947, and jhp0949 differed significantly between Western and East Asian isolates. In Western isolates, the presence of jhp0945 was significantly associated with gastric ulcer, duodenal ulcer, and gastric cancer (odds ratios [95% confidence intervals]: 2.27 [1.04 to 4.98], 1.86 [1.03 to 3.34], and 1.92 [1.03 to 3.56], respectively). jhp0940-positive Western isolates were significantly associated with absence of gastric ulcer or duodenal ulcer (0.21 [0.05 to 0.94] and 0.31 [0.12 to 0.78], respectively). No significant difference was observed between inflammatory cell infiltration or atrophy and the presence or absence of plasticity region genes. The outcome of H. pylori infections varies widely geographically. These data suggest a possible role for difference in the prevalence of plasticity region genes in the geographic variation in H. pylori-related diseases.
Sugimoto, M., Watada, M., Jung, S. W., Graham, D. Y., Yamaoka, Y.
Role of Helicobacter pylori Plasticity Region Genes in Development of Gastroduodenal Diseases [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 Escherichia coli is the most common cause of urinary tract infections (UTIs). E. coli genes epidemiologically associated with UTIs are potentially valuable in developing strategies for treating and/or preventing such infections as well as differentiating uropathogenic E. coli from nonuropathogenic E. coli. To identify E. coli genes associated with UTIs in humans, we combined microarray-based and PCR-based analyses to investigate different E. coli source groups derived from feces of healthy humans and from patients with cystitis, pyelonephritis, or urosepsis. The cjrABC-senB gene cluster, sivH, sisA, sisB, eco274, and fbpB, were identified to be associated with UTIs. Of these, cjrABC-senB, sisA, sisB, and fbpB are known to be involved in urovirulence in the mouse model of ascending UTI. Our results provide evidence to support their roles as urovirulence factors in human UTIs. In addition, the newly identified UTI-associated genes were mainly found in members of phylogenetic groups B2 and/or D.
Mao, B.-H., Chang, Y.-F., Scaria, J., Chang, C.-C., Chou, L.-W., Tien, N., Wu, J.-J., Tseng, C.-C., Wang, M.-C., Chang, C.-C., Hsu, Y.-M., Teng, C.-H.
Identification of Escherichia coli Genes Associated with Urinary Tract Infections [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 Pulsed-field gel electrophoresis (PFGE) analysis demonstrated that while 76% of patients had only one genotype of campylobacter, 10% carried two different but related genotypes (Dice coefficients > 0.78), and 14% carried at least two unrelated genotypes (Dice coefficients < 0.65). This supports the clustering of Campylobacter isolates with similar PFGE patterns, highlights the need to analyze multiple isolates from both sources and patients, and confirms that caution should be exercised before epidemiological links between patients or sources are dismissed.
Gilpin, B., Robson, B., Lin, S., Scholes, P., On, S.
Pulsed-Field Gel Electrophoresis Analysis of More than One Clinical Isolate of Campylobacter spp. from Each of 49 Patients in New Zealand [Epidemiology]
Date de mise en ligne : Vendredi 20 janvier 2012 We have developed a novel microsphere-based genotyping method for 46 mucosal human papillomavirus (HPV) types. HPV DNA was amplified by PCR using general primers and typed by hybridization to HPV type-specific probes coupled to sortable microspheres based on the Luminex xMAP technology. Hybridization to each probe was specific for each HPV type without cross-hybridization and sensitive enough to allow typing of HPV contained in clinical specimens. The method was validated with direct sequencing and the Roche Linear Array genotyping method.
Zubach, V., Smart, G., Ratnam, S., Severini, A.
Novel Microsphere-Based Method for Detection and Typing of 46 Mucosal Human Papillomavirus Types [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 HCV core antigen (Ag) and HCV RNA levels were evaluated in matched liver biopsy samples and sera from 22 patients with hepatitis C infection by using the quantitative Architect HCV Ag immunoassay and a real-time RT-qPCR assay, respectively. The data showed a strong correlation between liver and serum compartments of HCV Ag levels (r = 0.80) and HCV RNA levels (r = 0.87). In summary, the serum HCV Ag and RNA levels reflect the intrahepatic values.
Descamps, V., Op de Beeck, A., Plassart, C., Brochot, E., Francois, C., Helle, F., Adler, M., Bourgeois, N., Degre, D., Duverlie, G., Castelain, S.
Strong Correlation between Liver and Serum Levels of Hepatitis C Virus Core Antigen and RNA in Chronically Infected Patients [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Among 23 patients carrying methicillin-resistant Staphylococcus aureus (MRSA) in their anterior nares, 6 (26%) also carried methicillin-susceptible S. aureus (MSSA) as less prevalent flora. In 4 of the 6 patients, the MSSA was unrelated to prevalent MRSA, as determined by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and staphylococcal protein A (spa) typing. However, in two patients, the strains were identical except for the absence of spontaneous staphylococcal cassette chromosome mec (SCCmec). We consider this evidence of spontaneous SCCmec excision in vivo.
Boundy, S., Zhao, Q., Fairbanks, C., Folgosa, L., Climo, M., Archer, G. L.
Spontaneous Staphylococcal Cassette Chromosome mec Element Excision in Staphylococcus aureus Nasal Carriers [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 When 13 of 13 nasal wash specimens from a single pediatrician's office tested positive for low quantities of Bordetella pertussis DNA, we suspected prelaboratory contamination. Investigation revealed that Pentacel and Adacel vaccines contain high copy numbers of B. pertussis DNA, which can be aerosolized, causing false-positive B. pertussis PCR results.
Salimnia, H., Lephart, P. R., Asmar, B. I., Prebelich, D., Paulson, E., Fairfax, M. R.
Aerosolized Vaccine as an Unexpected Source of False-Positive Bordetella pertussis PCR Results [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 In Asia, blaKPC detection has been limited to East Asia and not yet seen in Southeast Asia. We report four blaKPC-2-containing Klebsiella pneumoniae isolates from two different hospitals in Singapore. All isolates belonged to strain type 11 (ST11) and were indistinguishable by pulsed-field gel electrophoresis (PFGE). blaKPC-2 was located on nonconjugative plasmids and flanked by mobile genetic structures composed of a partial Tn4401 transposon and a Tn3-based transposon which previously have been described only in Chinese isolates.
Balm, M. N. D., Ngan, G., Jureen, R., Lin, R. T. P., Teo, J.
Molecular Characterization of Newly Emerged blaKPC-2-Producing Klebsiella pneumoniae in Singapore [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 The modified Hodge test has an excellent sensitivity for detecting enterobacterial isolates producing Ambler class A (KPC) and class D (OXA-48) carbapenemases. Its sensitivity is low for NDM-1 producers (50%) but is increased to 85.7% by adding ZnSO4 (100 μg/ml) in the culture medium. However, this test has a low specificity and is time-consuming.
Girlich, D., Poirel, L., Nordmann, P.
Value of the Modified Hodge Test for Detection of Emerging Carbapenemases in Enterobacteriaceae [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 Vibrio cholerae O1 in a river water specimen in South Africa was reported, and a public health response followed in order to prevent an outbreak. Further investigation determined this to be a pseudoalert of V. cholerae O1, possibly linked to laboratory contamination. Following culture of bacteria from the water specimen, the testing laboratory possibly contaminated the culture with a V. cholerae O1 reference strain and then mistakenly reported isolation of V. cholerae O1.
Smith, A. M., Keddy, K. H., Ismail, H., Tau, N., Sooka, A., Archer, B. N., Thomas, J., Crisp, N.
Possible Laboratory Contamination Leads to Incorrect Reporting of Vibrio cholerae O1 and Initiates an Outbreak Response [Bacteriology]
Date de mise en ligne : Vendredi 20 janvier 2012 A multiplex real-time PCR assay and melting curve analysis for identifying 23 mycobacterial species was developed and evaluated using 77 reference strains and 369 clinical isolates. Concordant results were obtained for all 189 (100%) isolates of the Mycobacterium tuberculosis complex and 169 (93.9%) isolates of nontuberculous mycobacteria. Our results showed that this multiplex real-time PCR assay is an effective tool for the mycobacterial identification from cultures.
Kim, J.-U., Cha, C.-H., An, H.-K.
Multiplex Real-Time PCR Assay and Melting Curve Analysis for Identifying Mycobacterium tuberculosis Complex and Nontuberculous Mycobacteria [Mycobacteriology and Aerobic Actinomycetes]
Date de mise en ligne : Vendredi 20 janvier 2012 The aim of this study was to evaluate the reliability of the VersaTREK system for Mycobacterium tuberculosis drug susceptibility testing compared with results obtained with the Bactec MGIT 960 system. A total of 67 strains were evaluated. Overall agreement was at 98.5%. Kappa indexes were 1.0 for isoniazid, rifampin, and ethambutol, 0.937 for pyrazinamide, and 0.907 for streptomycin. The VersaTREK system is validated for M. tuberculosis drug susceptibility testing.
Espasa, M., Salvado, M., Vicente, E., Tudo, G., Alcaide, F., Coll, P., Martin-Casabona, N., Torra, M., Fontanals, D., Gonzalez-Martin, J.
Evaluation of the VersaTREK System Compared to the Bactec MGIT 960 System for First-Line Drug Susceptibility Testing of Mycobacterium tuberculosis [Mycobacteriology and Aerobic Actinomycetes]
Date de mise en ligne : Vendredi 20 janvier 2012 A multiplex-PCR Luminex xMAP bead probe fluid array using xTAG analyte-specific reagents (multiplex xTAG fungal ASR assay) was employed for detection of clinically significant Candida species, Cryptococcus neoformans, Histoplasma capsulatum, and Blastomyces dermatitidis from blood cultures. We tested 132 blood cultures negative (n = 10) or positive (n = 97) for yeasts and/or bacteria (n = 25). The assay showed sensitivity and specificity of 100% and 99%, respectively. The xTAG fungal ASR assay is a rapid assay that allows simultaneous identification of multiple yeast species.
Balada-Llasat, J.-M., LaRue, H., Kamboj, K., Rigali, L., Smith, D., Thomas, K., Pancholi, P.
Detection of Yeasts in Blood Cultures by the Luminex xTAG Fungal Assay [Mycology]
Date de mise en ligne : Vendredi 20 janvier 2012 We present an algorithm based on three PCR assays for Leishmania (Viannia) species identification and assessed its performance using 70 specimens from Peruvian patients. The succession of the assayed targets can be ordered according to species prevalence. Sequential progression through the algorithm reduced the number of samples here studied by approximately 30% after each step.
Veland, N., Boggild, A. K., Valencia, C., Valencia, B. M., Llanos-Cuentas, A., Van der Auwera, G., Dujardin, J.-C., Arevalo, J.
Leishmania (Viannia) Species Identification on Clinical Samples from Cutaneous Leishmaniasis Patients in Peru: Assessment of a Molecular Stepwise Approach [Parasitology]
Date de mise en ligne : Vendredi 20 janvier 2012 To investigate reinfection in patients with congenital cytomegalovirus (CMV) infection, we established a CMV subtype-specific real-time quantitative PCR method targeting the CMV gH epitope region that can be used for evaluating pathogenic CMV strains in cases of mixed CMV infection.
Ikuta, K., Ishioka, K., Sato, Y., Imamura, T., Asano, K., Koyano, S., Inoue, N., Suzutani, T.
A Novel Real-Time PCR Method for Determination and Quantification of Each Cytomegalovirus Glycoprotein H Subtype in Clinical Samples [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 Quantitative HIV RNA viral load (QVL) assays (Roche Diagnostics) were sensitive and specific when used to diagnose HIV infection in (i) HIV-exposed infants (sensitivity of 100% [63.1 to 100%] and specificity of 100% [97.9 to 100%]) and (ii) suspected acute HIV infection patients with a negative/indeterminate Western blot (sensitivity of 97.6% [91.6 to 99.7%] and specificity of 100% [96.1 to 100%]). No false-positive QVL results were identified.
Lee, B. E., Plitt, S. S., Jayaraman, G. C., Chui, L., Singh, A. E., Preiksaitis, J. K.
Use of Quantitative HIV RNA Detection for Early Diagnosis of HIV Infection in Infants and Acute HIV Infections in Alberta, Canada [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 We evaluated the prevalence of respiratory virus infection (RVI) in 403 illnesses of 364 persons hospitalized over a 2-year period with acute respiratory conditions using virus-specific reverse transcription-PCR (RT-PCR) assays in addition to cell culture and serology. RVIs were identified in >75% of children under 5 years of age and 25 to 37% of adults. The molecular assays doubled the number of infections identified; picornaviruses were the most frequent in patients of all ages, followed by respiratory syncytial virus and influenza viruses.
Atmar, R. L., Piedra, P. A., Patel, S. M., Greenberg, S. B., Couch, R. B., Glezen, W. P.
Picornavirus, the Most Common Respiratory Virus Causing Infection among Patients of All Ages Hospitalized with Acute Respiratory Illness [Virology]
Date de mise en ligne : Vendredi 20 janvier 2012 An outbreak of abortion affecting multiparous cows was associated with Hobi-like pestivirus infection. Viral RNA and antigens were detected in the tissues of two aborted fetuses. Molecular assays for other common abortogenic agents tested negative. At the genetic level, the Hobi-like pestivirus displayed the closest relatedness to Italian, Australian, and South American viruses, whereas it diverged from the prototype Thai isolate. These findings may have important implications for the pestivirus control/eradication programs in cattle herds.
Decaro, N., Lucente, M. S., Mari, V., Sciarretta, R., Pinto, P., Buonavoglia, D., Martella, V., Buonavoglia, C.
Hobi-Like Pestivirus in Aborted Bovine Fetuses [Clinical Veterinary Microbiology]
Date de mise en ligne : Vendredi 20 janvier 2012 Early extrapulmonary tuberculosis (EPTB) diagnosis is particularly difficult. Among 108 smear-negative extrapulmonary samples showing a positive culture for Mycobacterium tuberculosis complex (43 body fluids and 65 nonliquid specimens), 63 (58.3%) were positive with the Xpert MTB/RIF assay (GX). GX sensitivity was quite low for samples from sterile locations (especially for pleural fluids: 26.9%) but high for some nonliquid samples, like abscess aspirates (76.5%). In summary, GX may be a useful tool to be considered for EPTB diagnosis.
Moure, R., Martin, R., Alcaide, F.
Effectiveness of an Integrated Real-Time PCR Method for Detection of the Mycobacterium tuberculosis Complex in Smear-Negative Extrapulmonary Samples in an Area of Low Tuberculosis Prevalence [Mycobacteriology and Aerobic Actinomycetes]
Date de mise en ligne : Vendredi 20 janvier 2012 The development of a rapid test to identify Mycobacterium tuberculosis Beijing isolates and specifically strain GC1237, coming from a sub-Saharan country, is needed due to its alarming wide spread on Gran Canaria Island (Spain). A rapid test that detects IS6110 present between dnaA and dnaN in the Beijing strains and in a specific site for GC1237 (Rv2180c) has been developed. This test would be a useful tool in the surveillance of subsequent cases.
Millan-Lou, M. I., Alonso, H., Gavin, P., Hernandez-Febles, M., Campos-Herrero, M. I., Copado, R., Canas, F., Kremer, K., Caminero, J. A., Martin, C., Samper, S.
Rapid Test for Identification of a Highly Transmissible Mycobacterium tuberculosis Beijing Strain of Sub-Saharan Origin [Mycobacteriology and Aerobic Actinomycetes]
Date de mise en ligne : Vendredi 20 janvier 2012 Bacillus cereus is a rare cause of endocarditis, typically associated with intravenous drug abuse, rheumatic heart disease, prosthetic heart valves, pacemakers, or immunodeficiency. We present the first case of native valve Bacillus cereus endocarditis with no apparent risk factors. The patient had a fulminant course requiring emergent valve replacement.
Thomas, B. S., Bankowski, M. J., Lau, W. K. K.
Native Valve Bacillus cereus Endocarditis in a Non-Intravenous-Drug-Abusing Patient [Case Reports]
Date de mise en ligne : Vendredi 20 janvier 2012 Kytococcus schroeteri, a saprophyte of the human skin, may cause serious infections in the immunocompromised host. Here, we describe a case of pneumonia and bacteremia due to Kytococcus schroeteri in an immunocompromised patient, successfully treated with linezolid and trimethoprim-sulfamethoxazole.
Blennow, O., Westling, K., Froding, I., Ozenci, V.
Pneumonia and Bacteremia Due to Kytococcus schroeteri [Case Reports]
Date de mise en ligne : Vendredi 20 janvier 2012 This report documents emergence of New Delhi metallo-beta-lactamase (NDM-1) and Klebsiella pneumoniae carbapenemase (KPC-2) in K. pneumoniae and Enterobacter cloacae in South Africa. NDM-1 producers have not been described in South Africa, and this is the first instance that KPC producers have been identified in Africa. The two patients infected with these carbapenemase-producing bacteria demised.
Brink, A. J., Coetzee, J., Clay, C. G., Sithole, S., Richards, G. A., Poirel, L., Nordmann, P.
Emergence of New Delhi Metallo-Beta-Lactamase (NDM-1) and Klebsiella pneumoniae Carbapenemase (KPC-2) in South Africa [Case Reports]
Date de mise en ligne : Vendredi 20 janvier 2012 Helcococcus kunzii was isolated by sonication and conventional cultures obtained from a case of infection following total knee prosthesis in an immunocompetent patient. The patient recovered uneventfully. This is the first known case of an H. kunzii prosthetic joint infection.
Perez-Jorge, C., Cordero, J., Marin, M., Esteban, J.
Prosthetic Joint Infection Caused by Helcococcus kunzii [Case Reports]
Date de mise en ligne : Vendredi 20 janvier 2012 The disease spectrum associated with human bocavirus-1 infection remains to be fully defined. We report a case of bocavirus-1-associated bronchiolitis, leading to severe respiratory failure and extracorporeal membrane oxygenation in a 4-year-old child, and suggest blood testing for human bocavirus-1 in children with severe respiratory tract infection.
Edner, N., Castillo-Rodas, P., Falk, L., Hedman, K., Soderlund-Venermo, M., Allander, T.
Life-Threatening Respiratory Tract Disease with Human Bocavirus-1 Infection in a 4-Year-Old Child [Case Reports]
Date de mise en ligne : Vendredi 20 janvier 2012 We report a case of chest wall abscess caused by Mycobacterium bovis BCG that arose as a complication 1 year after intravesical BCG instillation. We identified M. bovis BCG Tokyo 172 in the abscess by PCR-based typing of Mycobacterium tuberculosis complex and analysis of variable number of tandem repeats data.
Kanamori, H., Isogami, K., Hatakeyama, T., Saito, H., Shimada, K., Uchiyama, B., Aso, N., Kaku, M.
Chest Wall Abscess Due to Mycobacterium bovis BCG after Intravesical BCG Therapy [Case Reports]
Date de mise en ligne : Vendredi 20 janvier 2012
Mo, F., Wyatt, A. W., Wu, C., Lapuk, A. V., Marra, M. A., Gleave, M. E., Volik, S. V., Collins, C. C.
Next-Generation Sequencing of Prostate Tumors Provides Independent Evidence of Xenotropic Murine Leukemia Virus-Related Gammaretrovirus Contamination [Letters To The Editor]
Date de mise en ligne : Vendredi 20 janvier 2012
Bark, C. M., Thiel, B. A., Johnson, J. L.
Pretreatment Time to Detection of Mycobacterium tuberculosis in Liquid Culture Is Associated with Relapse after Therapy [Letters To The Editor]
Date de mise en ligne : Vendredi 20 janvier 2012
Chow, J. M., Bauer, H. M., Bolan, G.
Repeating Low-Positive Nucleic Acid Amplification Test Results for Chlamydia trachomatis and Neisseria gonorrhoeae: Assessment of Current Practice in Selected California Public- and Private-Sector Laboratories [Letters To The Editor]
Date de mise en ligne : Vendredi 20 janvier 2012
Stensvold, C. R., Nielsen, H. V.
Comparison of Microscopy and PCR for Detection of Intestinal Parasites in Danish Patients Supports an Incentive for Molecular Screening Platforms [Letters To The Editor]
Date de mise en ligne : Vendredi 20 janvier 2012
Justesen, U. S., Holm, A., Knudsen, E., Andersen, L. B., Jensen, T. G., Kemp, M., Skov, M. N., Gahrn-Hansen, B., Moller, J. K.
Species Identification of Clinical Isolates of Anaerobic Bacteria: a Comparison of Two Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry Systems [Author's Correction]
Date de mise en ligne : Vendredi 20 janvier 2012
Burd, E. M., Sharp, S. E.
Answer to February 2012 Photo Quiz [Photo Quiz]