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1.
The incidence of syphilis in the Tuva Republic (geographical centre of Asia), Russia has been exceedingly high historically. No detailed examinations and no molecular investigations of Treponema pallidum strains transmitted in the Tuva Republic, or in general, in Russia, were published internationally. We examined the syphilis epidemiology in 1994–2013, and the molecular epidemiology and macrolide resistance in T. pallidum strains in 2013–2014 in the Tuva Republic. Among 95 mainly primary or secondary syphilis patients, the arp, tpr, tp0548 and 23S rRNA genes in 85 polA gene‐positive genital ulcer specimens were characterized. The syphilis incidence in Tuva Republic peaked in 1998 (1562), however declined to 177 in 2013. Among the 70 (82%) completely genotyped specimens, six molecular strain types were found. Strain type 14d/f accounted for 91%, but also 14c/f, 14d/g, 14b/f, 14i/f, 9d/f, and 4d/f were identified. Two (2.4%) specimens contained the 23S rRNA A2058G macrolide resistance mutation. This is the first internationally published typing study regarding T. pallidum in Russia, performed in the Tuva Republic with the highest syphilis incidence in Russia. The two molecular strain types 4d/f and 9d/f have previously been described only in Eastern and Northern China and for the first time, macrolide‐resistant syphilis was described in Russia.  相似文献   

2.
The objectives of this study were to evaluate the reproducibility of a molecular method for the subtyping of Treponema pallidum subsp. pallidum and to discriminate strains of this microorganism from strains from patients with syphilis. We studied 212 specimens from a total of 82 patients with different stages of syphilis (14 primary, 7 secondary and 61 latent syphilis). The specimens were distributed as follows: genital ulcers (n = 9), skin and mucosal lesions (n = 7), blood (n = 82), plasma (n = 82), and ear lobe scrapings (n = 32). The samples were assayed by a PCR technique to amplify a segment of the polymerase gene I (polA). Positive samples were typed on the basis of the analysis of two variable genes, tpr and arp. Sixty-two of the 90 samples positive for polA yielded typeable Treponema pallidum DNA. All skin lesions in which T. pallidum was identified (six of six [100%]) were found to contain enough DNA for typing of the organism. It was also possible to type DNA from 7/9 (77.7%) genital ulcer samples, 13/22 (59.1%) blood samples, 20/32 (62.5%) plasma samples, and 16/21 (76.2%) ear lobe scrapings. The same subtype was identified in all samples from the same patient. Five molecular subtypes (subtypes 10a, 14a, 14c, 14f, and 14g) were identified, with the most frequently found subtype being subtype 14a and the least frequently found subtype being subtype 10a. In conclusion, the subtyping technique used in this study seems to have good reproducibility. To our knowledge, subtype 10a was identified for the first time. Further studies are needed to explain the presence of this subtype in Portugal, namely, its relationship to the Treponema pallidum strains circulating in the African countries where Portuguese is spoken.Syphilis is a sexually transmitted infection caused by Treponema pallidum subsp. pallidum (T. pallidum) and has a worldwide distribution, which remains important due to its strong association with the increased rates of acquisition and transmission of the human immunodeficiency virus (1, 3, 6, 7).In Portugal and in accordance with the Portuguese General Direction of Health, there were 120 cases of recently acquired syphilis in 2006, which corresponds to an incidence rate of 1.20/105 population, and 19 cases of congenital syphilis, which corresponds to an incidence rate of 0.13/105 population, in the same year (2). However, when unpublished data from dermatology clinics in Portugal are taken into account (personal communications, 2002), syphilis is highly underreported.Until some years ago, strains of T. pallidum could not be differentiated. Identification of the organism was complicated and there was no means of sustainable culture for this microorganism, which can be cultured only in experimental animals. This makes understanding of the pathogenesis and epidemiology of T. pallidum difficult. A technique that uses a combination of PCR amplification and restriction fragment length polymorphism (RFLP) analysis of two different gene targets (arp and tpr) was developed and used as a molecular typing system to differentiate between strains of T. pallidum (12). The number of 60-bp tandem repeats within the arp gene, indicated by a lowercase letter that designates the RFLP profile of a segment of the tprE, trpG, and trpJ genes, supports this typing system.The capacity to differentiate strains of Treponema pallidum is important, since it makes it possible to know the diversity of circulating subtypes, to monitor changes in the prevalence and geographical distribution of the strains over time, and to determine which new strains have been introduced in a specific area.The present study, based on the subtyping system referred to above, had the following objectives: to evaluate the reproducibility of the molecular subtyping method and to discriminate strains of T. pallidum from patients with syphilis from one area of Lisbon, Portugal.  相似文献   

3.
The role of bacteria is unclear in the facial skin lesions caused by Demodex. To shed some light on this issue, we conducted a case-control study comparing cases with facial dermatoses with controls with healthy skin using denaturing gradient gel electrophoresis (DGGE) technique. The bacterial diversity, composition, and principal component were analyzed for Demodex bacteria and the matched facial skin bacteria. The result of mite examination showed that all 33 cases were infected with Demodex folliculorum (D. f), whereas 16 out of the 30 controls were infected with D. f, and the remaining 14 controls were infected with Demodex brevis (D. b). The diversity analysis showed that only evenness index presented statistical difference between mite bacteria and matched skin bacteria in the cases. The composition analysis showed that the DGGE bands of cases and controls were assigned to 12 taxa of 4 phyla, including Proteobacteria (39.37–52.78%), Firmicutes (2.7–26.77%), Actinobacteria (0–5.71%), and Bacteroidetes (0–2.08%). In cases, the proportion of Staphylococcus in Firmicutes was significantly higher than that in D. f controls and D. b controls, while the proportion of Sphingomonas in Proteobacteria was significantly lower than that in D. f controls. The between-group analysis (BGA) showed that all the banding patterns clustered into three groups, namely, D. f cases, D. f controls, and D. b controls. Our study suggests that the bacteria in Demodex should come from the matched facial skin bacteria. Proteobacteria and Firmicutes are the two main taxa. The increase of Staphylococcus and decrease of Sphingomonas might be associated with the development of facial dermatoses.  相似文献   

4.
Although detection of Treponema pallidum DNA in whole-blood specimens of syphilis patients has been reported, it is uncertain at what stage of the disease such specimens are most suitable for the molecular diagnosis of syphilis. Also, few studies have directly compared the different gene targets for routine laboratory diagnostic usage in PCR assays. We examined 87 specimens from 68 patients attending two urban sexually transmitted disease clinics in Alberta, Canada. PCR was used to amplify the T. pallidum tpp47, bmp, and polA genes as well as a specific region of the 23S rRNA gene linked to macrolide antibiotic susceptibility. In primary syphilis cases, PCR was positive exclusively (75% sensitivity rate) in ulcerative swabs but not in blood specimens, while in secondary syphilis cases, 50% of the blood specimens were positive by PCR. Four out of 14 (28.6%) of our PCR-positive syphilis cases were found to be caused by an azithromycin-resistant strain(s). Our results confirmed that swabs from primary ulcers are the specimens of choice for laboratory diagnostic purposes. However, further research is required to determine what specimen(s) would be most appropriate for molecular investigation of syphilis in secondary and latent syphilis.Syphilis, caused by the spirochete Treponema pallidum, is a complicated disease that can be divided into different stages (31). Other than in congenital or transfusion-acquired syphilis, T. pallidum gains access to the body through the mucus membranes, causing the primary lesion or chancre, which contains large numbers of the spirochete demonstrable by microscopy. It is believed that within a short time, the organism disseminates throughout the body via the bloodstream and/or lymphatics. Because T. pallidum cannot be grown on artificial culture media, laboratory diagnosis of syphilis is traditionally made by detection of the treponemal spirochetes in clinical specimens by using either microscopy (dark-field microscopy, silver staining, or fluorescent antibody staining), the rabbit infectivity test, or serology. Each of these approaches has its limitations. Dark-field microscopy requires the microscopist to have experience, and the method cannot reliably distinguish pathogenic T. pallidum from commensal spirochetes which may be present in some body sites. Fluorescent antibody staining using polyclonal antisera to T. pallidum has poor specificity (17). Although monoclonal antibody to the 37-kDa protein is specific (11), it is not widely available. Serology depends on the host''s development of either nontreponemal reaginic antibodies or specific antibody to T. pallidum. In the former case, responses to the cardiolipid antigens are also induced by other infectious agents or conditions and can therefore produce false-positive syphilis serology results (7). In the latter case, specific antibody response to treponemal antigens may be delayed, and hence, such tests may suffer from poor sensitivity during the early primary phase of infection. Furthermore, patients with low numbers of CD4+ lymphocytes as a result of human immunodeficiency virus infection may have an aberrant immune response and abnormal syphilis serology despite infection (10, 19). Finally, the rabbit infectivity test requires the use of live animals and live T. pallidum and has not been widely used in routine clinical diagnostic laboratories. Apart from these drawbacks, neither serology nor microscopy allows the microorganism to be characterized for epidemiologic study or for antibiotic susceptibility.Modern DNA technologies have enabled most clinical laboratories to implement molecular diagnostic approaches, including PCR, restriction fragment length polymorphisms, and DNA sequencing for the molecular characterization of pathogens. A molecular typing scheme that is based on the characterization of two T. pallidum repeat genes, arp and tpr, has been developed by Pillay et al. (26). Since T. pallidum cannot be cultured on artificial media, these modern techniques are well suited to complement existing techniques for laboratory investigation of syphilis infection.Over the past 2 decades, a number of investigators have described PCR procedures for the diagnosis of syphilis based on the detection of different T. pallidum gene targets (6, 8, 9, 14, 23, 33). Most of the procedures used swab specimens obtained from ulcers or cerebrospinal fluid (CSF). Although detection of T. pallidum DNA in whole blood has been reported (18, 30), it is uncertain at what stage of the disease such specimens are most suitable for PCR diagnosis of syphilis. To date, there have not been any studies to directly compare the different target genes for routine laboratory diagnostic usage in PCR assays.In Canada, PCR is not commonly used for laboratory investigation of syphilis. Therefore, we report our experience with using PCR to diagnose syphilis in various specimens, using PCR primers that target three different T. pallidum genes (bmp, tpp47, and polA) as well as a specific region of the 23S rRNA gene that has been linked to macrolide antibiotic resistance (15). Our objective is to study the suitability of different clinical specimens as well as the different T. pallidum gene targets for molecular diagnosis and characterization of syphilis in patients in Alberta, Canada. Alberta has been experiencing an outbreak of predominantly heterosexual infectious syphilis since 2001, with recent rises among men who have sex with men (MSM) (27).  相似文献   

5.
Staphylococcus argenteus is a novel Staphylococcus species closely related to Staphylococcus aureus that has been recently described. In this study, we investigated the proportion and the characteristics of S. argenteus recovered from humans in Belgium. S. aureus. human isolates collected in Belgium from 2006 to 2015 (n?=?1,903) were retrospectively characterised via the presence of non-pigmented colonies on chocolate agar, spa typing and rpoB sequencing to determine if some of them were in fact S. argenteus. Out of 73 strains non-pigmented on chocolate plates, 3 isolates (0.16 %) showed rpoB sequences, in addition to spa and sequence types (ST2250/t5787, ST2250/t6675, ST3240/t6675), related to S. argenteus. Two of them were methicillin-resistant, harbouring a SCCmec type IV. The three S. argenteus isolates carried genes (sak, scn) of the immune evasion cluster. This first Belgian nationwide analysis showed a low occurrence of S. argenteus. Further studies should be conducted to identify the distribution range and the clinical impact of this new species.  相似文献   

6.
Prevalence of invasive ß-haemolytic streptococci (BHS) at a tertiary care hospital and molecular diversity of S. pyogenes and S. dysgalactiae was studied. Between 2012 and 2016, all blood culture sets (n?=?55,839), CSF (n?=?8413) and soft tissue (n = 20,926) samples were analysed for BHS positivity using HYBASE software. Molecular profiles of 99 S. pyogenes and S. dysgalactiae were identified by sequencing of M protein genes (emm types) and multiplex PCR typing of 20 other virulence determinants. Streptococci contributed to 6.2% of blood, 10.7% of CSF and 14.5% of soft tissue isolates, being among the most common invasive isolates. The overall rates of invasive S. pyogenes, S. agalactiae, S. dysgalactiae and S. pneumoniae were 2.4, 4.4, 2.1, and 5.3%. Whereas S. pneumoniae was 1.5% more common in CSF samples, BHS isolates were 2-fold and 11-fold higher in bacteraemia and invasive soft tissue infections. Genetic BHS typing revealed wide molecular diversity of invasive and noninvasive group A and group G BHS, whereas one emm-type (stG62647.0) and no other virulence determinants except scpA were detected in invasive group C BHS. BHS were important invasive pathogens, outpacing S. pneumoniae in bacteraemia and invasive soft tissue infections. The incidence of S. dysgalactiae infections was comparable to that of S. pyogenes even with less diversity of molecular virulence. The results of this study emphasise the need for awareness of BHS invasiveness in humans and the need to develop BHS prevention strategies.  相似文献   

7.
The purpose of this study is to characterize Streptococcus suis isolates recovered from human infections regarding serotype distribution, genotypic profile, clinical manifestations, and epidemiology. A total of 668 S. suis isolates recovered from human infections in Thailand were characterized based on serotyping by multiplex PCR and co-agglutination, genotypic profiles by multilocus sequence typing, and PCR for virulence-associated genes, as well as review of medical records. Serotype 2 (94.6%) was predominant, followed by serotype 14 (4.5%), 24 (0.45%), 5 (0.3%), and 4 (0.15%). Multilocus sequence typing analyses revealed seven clonal complexes (CC): CC1 (56.43%), CC104 (31.74%), CC233/379 (5.4%), CC25 (4.5%), CC28 (0.9%), CC221/234 (0.6%), CC94 (0.15%), and two singletons. The CC1 group contained serotype 2 and 14 isolates, while CC25, 28, 104, and 233/379 consisted of serotype 2 isolates only. CC221/234 contained serotype 5 and 24 isolates, whereas the single serotype 4 isolate belonged to CC94. Two singletons contained serotype 5 (ST235) and 2 (ST236) isolates. Our data showed that ST1 isolates were more associated with meningitis than those of other STs (p?<?0.001). The major route of infection was shown to be close contact with infected pigs or contaminated raw pork-derived products, including occupational exposure and recent consumption of raw pork products. This study revealed a relatively large number of CCs of S. suis causing human infection in Thailand. Among them, CC1 followed by CC104, with serotype 2 isolates, are predominant. Food safety campaigns and public health interventions would be important for controlling the S. suis infection in humans.  相似文献   

8.
Previously, a small study showed that 14f was the predominant subtype of Treponema pallidum in Shanghai, China. The result was quite different from the genotype distribution in other areas of China. This study aimed to identify the strain types of Treponema pallidum in samples collected over a 5-year period in Shanghai. From 2007 to 2011, genital swabs were collected from patients with syphilis from the Shanghai Skin Disease Hospital. Positive specimens were typed by the enhanced typing method by adding a tp0548 gene to the existing arp and tpr genotype system. In total, 304 of the 372 enrolled patients yielded fully typeable DNA. Ten arp types (4, 6, 8, 9, 11, 12, 13, 14, 15, and 19), 3 tpr types (a, d, and o), and 5 tp0548 types (a, c, f, g, and i) were identified. In total, 12 subtypes were identified with a combination of the arp and tpr genes. Subtype 14d was found in 270 samples (88.8%). When the combination included the tp0548 gene, the 12 CDC subtypes identified were divided into 14 strain types. The predominant type was 14d/f (88.8%), followed by 15d/f (3.6%), 13d/f (1.3%), and 19d/c (1.3%). Two of the 44 14d/f-infected patients and both of the 19d/c-infected patients who underwent a lumbar puncture were diagnosed with neurosyphilis. This study showed that the predominant type in Shanghai was 14d/f. While this is in keeping with data from other areas in China, it is different from an earlier report showing that 14f is the most common genotype in Shanghai. Further studies are needed to better understand the association between strain types and neurosyphilis.  相似文献   

9.
Microsporidiosis is an important zoonotic disease, even leading to severe diarrhea. However, no information about prevalence and genotypes of Enterocytozoon bieneusi infection in Asiatic black bears in southwestern China is available. The objectives of the present study were to investigate the prevalence of E. bieneusi and to characterize their genotypes using the nested PCR amplification of the internal transcribed spacer region of the ribosomal RNA gene cluster and multilocus sequence typing (MLST). The overall prevalence of E. bieneusi was 19.75% (80/405) and the rate of E. bieneusi in Xishuangbanna (33.33%) was significantly higher than that in any other regions (Honghe, 17.65%; Dehong, 13.04%; Kunming, 0; P?=?0.01). Sequence analysis revealed that 4 known genotypes (D, n?=?2; SC02, n?=?10; SC01, n?=?5; and CHB1, n?=?4) and 13 novel genotypes (designed MJ1–MJ13) were identified. When 17, 5, 14, and 34 sequences at loci MS1, MS3, MS4, and MS7 via MLST analyses, representing 4, 4, 5, and 10 genotypes, respectively, were completed, one multilocus genotype (MLG novel-ABB1) was identified. This is the first report of E. bieneusi in Asiatic black bear in Yunnan province, Southwestern China. The results indicated the potential zoonotic risk of this parasite through the Asiatic black bear in this region and provided foundation data for preventing and controlling E. bieneusi infection of many other animals and humans in these regions.  相似文献   

10.
The prevalence of carbapenem-resistant Acinetobacter baumannii in Saudi Arabia and their resistance genetic mechanisms are yet to be identified. We studied the prevalence and genetic diversity of extended-spectrum beta-lactamase genes, particularly the PER-1 gene, among carbapenem-resistant A. baumannii strains from patients at a tertiary care hospital in Riyadh, Saudi Arabia between 2006 and 2014. Fresh subcultured samples were tested for antimicrobial susceptibility minimum inhibitory concentration (MIC). Total genomic DNA was extracted from each isolate and further used for polymerase chain reaction (PCR) genotyping, sequence-based typing (SBT) of PER-1 and OXA-51-like gene, and multilocus sequence typing (MLST) of positive isolates. Randomly selected clinical isolates (n = 100) were subjected to MLST. A total of 503 isolates were characterized as multidrug-resistant (MDR) using the MIC. Isolates were further PCR tested for bla -TEM and bla -PER-1 resistance genes (n = 503). The genotyping results showed that 68/503 (14 %) isolates were positive to bla TEM. The genotyping results of PER-1-like genes showed that 384/503 (76.3 %) were positive among MDR Acinetobacter isolates. Based on SBT, the majority of these isolates were clustered into three main groups including isolates harboring PER-1: AB11 (bla -PER-1), isolate AB16 (bla -PER-1), and, finally, the plasmid pAB154 (bla -PER-7). Remarkably, many isolates were concealing the PER-1 gene and harboring the TEM resistance genes as well. MLST results for selected isolates (n = 100) identified four main sequence types (STs: 2, 19, 20, and 25) and four novel isolates (ST 486–489). We report 76.3 % prevalence of the PER-1 resistance gene among Acinetobacter clinical isolates from Riyadh, Saudi Arabia. Further work is needed to explore the clinical risks and patient outcome with such resistance related to healthcare-associated infections and investigate the genetic and molecular mechanisms that confer the MDR phenotype.  相似文献   

11.
The purpose of this study was to investigate the clinical characteristics of hypervirulent K. pneumoniae (hvKP) induced ventilator-associated pneumonia (VAP) and the microbiological characteristics and epidemiology of the hvKP strains. A retrospective study of 49 mechanically ventilated patients with K. pneumoniae induced VAP was conducted at a university hospital in China from January 2014 to December 2014. Clinical characteristics and K. pneumoniae antimicrobial susceptibility and biofilm formation were analyzed. Genes of capsular serotypes K1, K2, K5, K20, K54 and K57 and virulence factors plasmid rmpA(p-rmpA), iroB, iucA, mrkD, entB, iutA, ybtS, kfu and allS were also evaluated. Multilocus sequence typing (MLST) and random amplified polymorphic DNA (RAPD) analyses were used to study the clonal relationship of the K. pneumoniae strains. Strains possessed p-rmpA and iroB and iucA were defined as hvKP. Of 49 patients, 14 patients (28.6 %) were infected by hvKP. Antimicrobial resistant rate was significantly higher in cKP than that in hvKP. One ST29 K54 extended-spectrum-beta-lactamase (ESBL) producing hvKP strain was detected. The prevalence of K1 and K2 in hvKP was 42.9 % and 21.4 %, respectively. The incidences of K1, K2, K20, p-rmpA, iroB, iucA, iutA, Kfu and alls were significantly higher in hvKP than those in cKP. ST23 was dominant among hvKP strains, and all the ST23 strains had identical RAPD pattern. hvKP has become a common pathogen of VAP in mechanically ventilated patients in China. Clinicians should increase awareness of hvKP induced VAP and enhance epidemiologic surveillance.  相似文献   

12.
Spa typing has been shown to function as a genetic marker for Staphylococcus aureus outbreak investigations and epidemiological studies. This study was aimed to investigate biofilm formation capacity and spa gene polymorphism in methicillin resistant S. aureus (MRSA) strains isolated from clinical samples. A total of 102 S. aureus isolated during 2016, were analyzed for methicillin resistance and biofilm formation using phenotypic assays and PCR-based detection of associated genes. The polymorphic region of the spa gene was amplified by PCR using specific primers and subsequently in MRSA strains the amplified products were sequenced and spa types determined by using the spa database website. Out of 102 S. aureus, 41 isolates (40.2%) recognized as MRSA in phenotypic and genotypic investigations. In phenotypic assay, biofilm forming ability was detected in 71 isolates. The frequency of icaA and fnbA in test isolate were 53.9 and 65.7% respectively. Amplification of polymorphic region of the spa gene in all 102 tested isolates resulted in eight size fragments ranged between 168–336 bp. In MRSA strains thirteen distinct spa types with 5–12 repeats were observed. The most frequent types of spa were t030, t037, t325, t421, t937, t1814 and t084. spa types t2421, t1814, t359 and t2617 identified for the first time in Iran. The present results showed high biofilm formation capacity and great diversity of variable region of spa gene in MRSA strains and confirmed that, spa typing provides valuable information on the epidemiologic features and discrimination of this bacterium.  相似文献   

13.
Data on the molecular epidemiology of Bordetella pertussis are limited in developing countries where whole-cell pertussis vaccines (WCVs) have been used. The aim of this study was to determine the genotypes of circulating B. pertussis in China by direct molecular typing of clinical specimens. DNA extracts of 122 nasopharyngeal swabs (NPs) positive for B. pertussis by polymerase chain reaction (PCR) (targeting IS481 and ptx-Pr) from 2012 to 2013 were used for typing using the multiple-locus variable number tandem repeat analysis (MLVA) and also by PCR-based multilocus sequence typing (MLST) of B. pertussis virulence genes (ptxP, prn, and fim3). One hundred and eight DNA extracts (89 %) generated a complete MLVA type (MT). Among the 18 MTs obtained, MT55 (52 %) and MT104 (13 %) were the most common. MT27, which is linked to the ptxP3 allele and is prevalent in many developed countries using acellular pertussis vaccines (ACVs), was only found in 7 (6 %) DNA extracts. Eighty-seven DNA extracts (71 %) produced a complete multiantigen sequence typing (MAST) type. Of them, 77 (89 %) had the ptxP1/prn1/fim3-1 allele profile. Four DNA extracts (5 %) had the ptxP3/prn2/fim3-2 profile and 3 (4 %) had the ptxP3/prn1/fim3-2 allele profile. These seven DNA extracts also harbored MT27. Our result shows that B. pertussis circulating in China was different from those found in countries where ACVs have been in use, supporting the notion that selection pressure induced by WCVs and ACVs on the bacterial population differs.  相似文献   

14.
The aim of this study was to investigate human invasive isolates of enterococci, obtained through prospective surveillance in Poland. The consecutive enterococcal isolates were collected in 30 hospitals between May 2010 and June 2011, and studied by species identification, antimicrobial susceptibility testing and, for Enterococcus faecium by detection of markers specific for the hospital meroclone, multilocus VNTR analysis (MLVA) and multilocus sequence typing (MLST). Additionally, the genomic difference regions (GDRs) characteristic for lineage 78 were searched by PCR. Among 259 isolates, a nearly equal number of Enterococcus faecalis (n?=?140; 54.1 %) and E. faecium (n?=?112; 43.2 %) was found. The observed 14-day mortality rate of infected patients reached 18.1 %. All isolates were susceptible to linezolid and daptomycin. High-level aminoglycoside resistance occurred in over 50 % of isolates. Vancomycin resistance mediated by vanA or vanB was detected in 7.1 % of E. faecium; 71.4 % of isolates were multidrug resistant. E. faecium isolates ubiquitously carried molecular markers of hospital-associated meroclone (IS16, esp Efm , intA of ICEEfm1) and multilocus sequence typing showed the domination of representatives of lineages 78 and 17/18 (52.7 % and 46.4 %, respectively). Isolates of lineage 78 were significantly enriched in all the GDRs studied. The recent spread of E. faecium from this lineage contributed to the observed increase of E. faecium in enterococcal invasive infections in hospitals in Poland.  相似文献   

15.
The goal of this work was to obtain genotypic characteristics of multidrug-resistant (MDR) strains of Mycobacterium tuberculosis (i.e., strains that are resistant at least to rifampicin and isoniazid) isolated from consumptives in Northwestern Russia in 2011–2012. Spoligotyping of 195 strains of Mycobacterium tuberculosis revealed 14 spolingotypes belonging to genetic families Beijing (n = 162), LAM (n = 15), H3/URAL (n = 14), T, Harleem, and X. Spolingotypes SIT1 (Beijing), SIT42 (LAM), and SIT62 (H3/URAL) were predominant. Regardless of genotype, all studied strains were resistant to streptomycin. Multidrug-resistant strains were resistant to ethionamide (56%), amikacin (31%), kanamycin (40%), and capreomycin (33%). The fractions of the strains resistant to ethambutol were 71 (n = 115) and 42% (n = 14) among the Beijing and nonBeijing strains, respectively (p < 0.05). Representatives of the Beijing genetic family remain predominant in Northwestern Russia in the population of multidrug-resistant strains of Mycobacterium tuberculosis (83%).  相似文献   

16.
Carbapenem-resistant Enterobacteriaceae represents a major public health issue. This study investigated the clonality and resistance mechanisms of 92 carbapenem-resistant E. coli (n?=?21) and K. pneumoniae (n?=?71) isolates collected consecutively from clinical specimens and patients at high risk of carriage between 2010 and 2012 in a healthcare region in Hong Kong. Combined disk tests (CDTs) and the Carba NP test were used for phenotypic detection of carbapenemases. PCR assays were used to detect carbapenemase genes. All isolates were intermediate or resistant to at least one carbapenem. Nine (9.8 %) isolates were genotypic carbapenemase producers and included six K. pneumoniae (one ST1306/bla IMP-4, one ST889/bla IMP-4, two ST11/bla KPC-2, one ST258/bla KPC-2, one ST483/bla NDM-1) and three E. coli (one ST131/bla IMP-4, two ST744/ bla NDM-1) isolates. All nine isolates carrying carbapenemase genes could be detected by the CDTs and the Carba NP test. PCR identified bla CTX-M and bla AmpC alone or in combination in 77.8 % (7/9) and 96.4 % (80/83) of the carbapenemase-producers and non-producers, respectively. Porin loss was detected in 22.2 % (2/9) and 59.0 % (49/83) of the carbapenemase-producers and non-producers, respectively. Overall, the E. coli clones were diverse (14 different STs), but 36.6 % (26/71) of the K. pneumoniae isolates belonged to ST11. In conclusion, the prevalence of carbapenemases among carbapenem-nonsusceptible E. coli and K. pneumoniae remained low in Hong Kong. Porin loss combined with AmpC and/or CTX-M type ESBL was the major mechanism of carbapenem resistance in the study population.  相似文献   

17.
Cryptococcosis, caused by Cryptococcus gattii sensu lato, is an emerging disease that was initially found in (sub)tropical regions but recently expanded to temperate regions. Cryptococcus gattii s.l. infections are mostly encountered in healthy individuals, frequently affecting both lungs and the central nervous system (CNS). Usually, C. gattii s.l. is less susceptible to antifungal compounds than its counterpart, C. neoformans s.l. We studied 18 clinical C. gattii s.l. isolates with amplified fragment length polymorphism (AFLP) fingerprinting, mating-typing, multi-locus sequence typing (MLST) and antifungal susceptibility testing. All isolates were C. deuterogattii (genotype AFLP6/VGII), 14 were mating-type α and four were type a. Amphotericin B, itraconazole, voriconazole, posaconazole and isavuconazole showed high activity, with minimum inhibitory concentration (MIC) ranges of 0.063–0.25, 0.031–0.25, 0.031–0.25, 0.031–0.25 and <0.016–0.25 μg mL?1, respectively. Fluconazole and flucytosine had high geometric mean MICs of 2.07 and 3.7 μg mL?1, respectively. Most cases occurred in immunocompetent patients (n?=?10; 55.6 %) and CNS involvement was the most common clinical presentation (n?=?14; 77.8 %). Three patients (16.7 %) showed sequelae, hyperreflexia, dysarthria, diadochokinesia, anosmia and upper limb weakness. In conclusion, all infections were caused by C. deuterogattii (AFLP6/VGII) and the majority of patients were immunocompetent, with the CNS as the most affected site. All antifungal drugs had high in vitro activity against C. deuterogattii isolates, except fluconazole and flucytosine.  相似文献   

18.
To analyse the antimicrobial phenotype, carbapenem mechanisms, integrons, virulence factors and molecular typing of 164 Pseudomonas aeruginosa isolates recovered from lower tract respiratory samples in a Spanish hospital (1 year) as well as the patients’ clinical data. Susceptibility testing to 12 antipseudomonal agents was determined by microdilution and metallo-beta-lactamase (MBL) phenotype by double disc method. The oprD gene was studied by PCR, sequencing and comparison with P. aeruginosa PAO1 sequence. Detection and characterisation of MBLs, class 1, 2 and 3 integrons, and virulence genes were studied by PCR and sequencing. The prevalence of carbapenem-resistant P. aeruginosa (CRPA) was 26.8%. MBL phenotype was detected in 52.3% CRPA, and all of them were disseminated throughout the intensive care unit. Most of the MBL-carrying patients presented respiratory disease, mechanical ventilation, tracheostomy, bacteraemia, ≥?30 hospitalisation days and previous treatment with carbapenems and/or ≥?3 different antimicrobial families. The blaVIM-2 gene was the unique MBL encoding gene and was detected inside class 1 integrons. The class 1 integrons detected in 39 strains (23.8%) were associated with aminoglycosides (aadB, aadA1, aadA6, aacA4, aac(3)-I) and carbapenems resistance genes (blaVIM-2). The aac(3)-I?+?aadA1 and blaVIM-2 arrangements were the most prevalent ones. Thirty-one different PFGE patterns and 4 STs (ST175, ST235, ST253, ST973) were detected among the 39 intI1-positive isolates, being ST235 the most frequent. CRPA showed a great variety of alterations in oprD gene. The exoU+/exoS? genotype was detected in 82.6% of blaVIM-2-producing strains (ST235) and the exoU?/exoS+ in the remaining 17.4% (ST973).  相似文献   

19.
Plasmid-mediated AmpC (pAmpC) and ESBL co-production was detected in Escherichia coli a major etiologic agent of urinary tract infection. Isolates resistant to cefoxitin by CLSI methodology were tested for pAmpC beta-lactamase using phenylboronic acid and ESBLs by combined disk diffusion method. pAmpC/ESBL genes were characterized by PCR and sequencing. Transconjugation experiments were done to study the transfer of pAmpC and ESBL production from clinical isolates as donor to E. coli J53 AziR as recipient. Incompatibility groups of transmissible plasmids were classified by PCR-based replicon typing (PBRT). Among 148 urine culture positive isolates, E. coli was reported in 39.86 % (59/148), with 93.22 % (55/59) of cefoxitin resistance. pAmpC production was detected in 25, with varied distribution of blaCMY-2 and blaDHA-1type genes alone (n?=?13 and 7 respectively) or in combination (n?=?5). ESBL co-production was observed in 88 % (22/25) of pAmpC producing isolates with predominance of blaTEM (n?=?20). Twenty-three transconjugants showed transmission of pAmpC-and ESBL-resistant genes with co-carriage of blaCMY-2 and blaTEM (n?=?15) in plasmids of IncF type (n?=?9) being predominant, followed by IncI1 (n?=?4) and IncH1 (n?=?2) in combination. All clinical isolates were clonally diverse. Resistance against different beta-lactams in uropathogenic E. coli has been an emerging concern in resource- poor countries such as India. Knowledge on the occurrence of AmpC beta-lactamases and ESBL amongst this pathogen and its transmission dynamics may aid in hospital infection control.  相似文献   

20.
We present data on helminths harboured by two sympatric species of Enyalius Wagler, 1830 (E. iheringiii Boulenger, 1885 and E. perditus Jackson, 1978) from the Atlantic Rainforest of the Ilha de São Sebastião, in São Paulo state, southeastern Brazil. Six helminth species were found in the hosts: five nematodes (Cosmocerca sp., Oswaldocruzia burseyi Durette-Desset, Anjos et Vrcibradic, 2006, Oswaldocruzia fredi Durette-Desset, Anjos et Vrcibradic, 2006, Rhabdias sp., and Strongyluris oscari Travassos, 1923), and one acanthocephalan (Acanthocephalus sp.). Overall helminth prevalences were relatively high for both species [6/6 (100%) for E. iheringii and 9/14 (64%) for E. perditus]. The helminth assemblages from both host species were depauperate and dominated by generalist helminths with direct life-cycles.  相似文献   

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