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1.
BMC Infect Dis ; 20(1): 277, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293302

RESUMO

BACKGROUND: Clostridium difficile infection (CDI), especially hospital-acquired Clostridium difficile infection (HA-CDI), continues to be a public health problem and has aroused great concern worldwide for years. This study aimed to elucidate the clinical and epidemiological features of HA-CDI and the characteristics of C.difficile isolates in Chongqing, Southwest China. METHODS: A case-control study was performed to identify the clinical incidence and risk factors of HA-CDI. C. difficile isolates were characterised by polymerase chain reaction (PCR) ribotyping, multilocus sequence typing (MLST), toxin gene detection and antimicrobial susceptibility testing. RESULTS: Of the 175 suspicious patients, a total of 122 patients with antibiotic-associated diarrhea (AAD) were included in the study; among them, 38 had HA-CDI. The incidence of AAD and HA-CDI was 0.58 and 0.18 per 1000 patient admissions, respectively. Chronic renal disease and cephalosporin use were independent risk factors for HA-CDI. Fifty-five strains were assigned into 16 sequence types (STs) and 15 ribotypes (RTs). ST2/RT449 (8, 14.5%) was the predominant genotype. Of the 38 toxigenic isolates, A + B + CDT- isolates accounted for most (34, 89.5%) and 1 A + B + CDT+ isolate emerged. No isolate was resistant to vancomycin, metronidazole or tigecycline, with A-B-CDT- being more resistant than A + B + CDT-. CONCLUSIONS: Different genotypes of C. difficile strains were witnessed in Chongqing, which hinted at the necessary surveillance of HA-CDI. Adequate awareness of patients at high risk of HA-CDI acquisition is advocated and cautious adoption of cephalosporins should be highlighted.


Assuntos
Infecções por Clostridium/epidemiologia , Clostridium difficile/genética , Infecção Hospitalar/epidemiologia , Hospitais de Ensino , Centros de Atenção Terciária , Adulto , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , China/epidemiologia , Infecções por Clostridium/dietoterapia , Clostridium difficile/efeitos dos fármacos , Clostridium difficile/isolamento & purificação , Infecção Hospitalar/microbiologia , Diarreia/induzido quimicamente , Diarreia/epidemiologia , Diarreia/microbiologia , Feminino , Humanos , Incidência , Masculino , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Ribotipagem , Fatores de Risco , Vancomicina/uso terapêutico
2.
Emerg Microbes Infect ; 9(1): 631-638, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32183606

RESUMO

Clostridioides difficile infection (CDI) is a common cause of nosocomial diarrhea and can sometimes lead to pseudo-membranous colitis and toxic megacolon. We previously reported that the PCR ribotype 002 was a common C. difficile ribotype in Hong Kong that was associated with increased mortality. In this study, we assessed in vitro bacteriological characteristics and in vivo virulence of ribotype 002 compared to other common ribotypes, including ribotypes 012, 014 and 046. We observed significantly higher toxin A (p < 0.05) and toxin B (p < 0.05) production, sporulation (p < 0.001) and germination rates (p < 0.0001) in ribotype 002 than other common ribotypes. In a murine model of C. difficile infection, ribotype 002 caused significantly more weight loss (p < 0.001) and histological damage (p < 0.001) than other common ribotypes. These findings may have contributed to the higher prevalence and mortality observed, and provided mechanistic insights that can help public surveillance and develop novel therapeutics to combat against this infection.


Assuntos
Clostridiales/patogenicidade , Infecções por Bactérias Gram-Positivas/microbiologia , Animais , Hong Kong , Masculino , Camundongos Endogâmicos C57BL , Ribotipagem , Virulência
3.
Bratisl Lek Listy ; 121(3): 182-187, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115974

RESUMO

BACKGROUND: Clostridium (Clostridioides) difficile is the most common pathogen of nosocomial and antibiotic-related diarrhea in health-care facilities. The aim of the analysis was to show the testing algorithm and to identify hypervirulent strains (suspected RT 027). METHODS: The retrospective analysis of patient samples suspected on CDI was carried out by a two-step algorithm. Biological specimens were analysed by GDH or culture, immunoenzymatic assay on toxins A/B and selected samples also by a real-time PCR. RESULTS: In 1006 specimen suspected on CDI, 202 specimens were evaluated as positive in the two-step algorithm. Conflicting results (64 C. difficile isolates) were tested in a three-step algorithm by a real-time PCR and revealed 59 toxigenic and non RT 027 ribotypes. Statistically significant dependence among the independent variables, such as: diagnostic parameters and length of hospitalization (p = 0.175) and C. difficile (suspected RT027) ribotypes was not found. CONCLUSION: The results of PCR ribotyping showed a high prevalence of hypervirulent and toxigenic ribotypes in the studied sample. A resistance to vancomycin was found in one isolate. The PCR method contributed to the rapid laboratory diagnosis and thus treatment of high risk patients or was used as a third step in in the case of unclear results of standard diagnostic methods(Tab. 1, Fig. 4, Ref. 18). Text in PDF www.elis.sk.


Assuntos
Infecções por Clostridium , Clostridium difficile , Ribotipagem , Algoritmos , Proteínas de Bactérias/análise , Proteínas de Bactérias/genética , Infecções por Clostridium/diagnóstico , Clostridium difficile/genética , Humanos , Estudos Retrospectivos
4.
Emerg Microbes Infect ; 9(1): 341-347, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32037964

RESUMO

Clostridioides difficile infection (CDI) is the most prevalent healthcare-associated infection in the United States and carries a significant healthcare system burden. As part of an ongoing, active surveillance system of C. difficile throughout Texas, the objective of this study was to assess changes in C. difficile ribotypes of clinical isolates obtained from hospitalized patients in Texas over the past seven years. Fifty hospitals located in Texas, USA sent C. difficile positive stool specimens to a centralized laboratory for PCR ribotyping and toxin characterization between 2011 and 2018. Data collected included specimen collection date, patient age, and sex. Strain genotypes were compiled, and changes in ribotype distribution over time were assessed. Overall, 7796 samples were ribotyped from predominately female patients (58.4%) aged 62 ± 19 years. Samples were obtained from all geographic regions of Texas including Houston/Southwest region (n = 5129; 85%), Dallas/North Texas (n = 579, 9.6%), Central Texas (n = 164; 2.7%), and South Texas (n = 162; 2.6%). The 10 most common ribotypes comprised 73% of all isolates tested during the study period. The most common ribotypes were 027 (17.5%), followed by 014-020 (16.1%), 106 (11.6%), and 002 (9.1%). The prevalence of ribotypes 027, 001, and 078-126 declined significantly over time, while ribotypes 106 and 054 increased in prevalence (P < 0.001). Furthermore, the emergence of a novel ribotype 255 strain was observed. Differences in ribotype distribution were also noted based on age and geographic distribution (P < 0.001, each). This seven-year study demonstrated changing molecular epidemiology of C. difficile in Texas, including the emergence of a novel ribotype 255.


Assuntos
Infecções por Clostridium/microbiologia , Clostridium difficile/classificação , Ribotipagem , Adulto , Idoso , Técnicas de Tipagem Bacteriana , Infecções por Clostridium/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Reação em Cadeia da Polimerase , Prevalência , Texas
5.
BMC Cardiovasc Disord ; 20(1): 32, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992206

RESUMO

BACKGROUND: The gut microbiome plays an important role in various cardiovascular diseases, such as atherosclerosis and hypertension, which are associated with abdominal aortic aneurysms (AAAs). METHODS: Here, we used 16S rRNA sequencing to explore gut microbiota in C57BL ApoE-/- mice with AAAs. A mouse model of abdominal aortic aneurysms was induced with angiotensin II (Ang II) (1000 ng/min per kg). On day 28 after the operation, fecal samples were collected and stored at - 80 °C until DNA extraction. We determined the relative abundances of bacterial taxonomic groups using 16S rRNA amplicon metabarcoding, and sequences were analyzed using a combination of mother software and UPARSE. RESULTS: We found that the gut microbiome was different between control and AAA mice. The results of correlation analysis between AAA diameter and the gut microbiome as well as LEfSe of the genera Akkermansia, Odoribacter, Helicobacter and Ruminococcus might be important in the progression of AAAs. CONCLUSIONS: AAA mice is subjected to gut microbial dysbiosis, and gut microbiota might be a potential target for further investigation.


Assuntos
Aneurisma da Aorta Abdominal/microbiologia , Bactérias/crescimento & desenvolvimento , Microbioma Gastrointestinal , Intestinos/microbiologia , Angiotensina II , Animais , Aneurisma da Aorta Abdominal/induzido quimicamente , Bactérias/genética , Bactérias/isolamento & purificação , Modelos Animais de Doenças , Disbiose , Fezes/microbiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Ribotipagem
6.
Int J Infect Dis ; 90: 111-115, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31707136

RESUMO

AIM: To obtain standardized epidemiological data for Clostridium difficile infection (CDI) in Slovakia. METHODS: Between October and December 2016, 36 hospitals in Slovakia used the European Centre for Disease Prevention and Control (ECDC) Clostridium difficile infection (CDI) surveillance protocol. RESULTS: The overall mean CDI incidence density was 2.8 (95% confidence interval 1.9-3.9) cases per 10 000 patient-days. Of 332 CDI cases, 273 (84.9%) were healthcare-associated, 45 (15.1%) were community-associated, and 14 (4.2%) were cases of recurrent CDI. A complicated course of CDI was reported in 14.8% of cases (n=51). CDI outcome data were available for 95.5% of cases (n=317). Of the 35 patients (11.1%) who died, 34 did so within 30 days after their CDI diagnosis. Of the 78 isolates obtained from 12 hospitals, 46 belonged to PCR ribotype 001 (59.0%; 11 hospitals) and 23 belonged to ribotype 176 (29.5%; six hospitals). A total of 73 isolates (93.6%) showed reduced susceptibility to moxifloxacin (ribotypes 001 and 176; p< 0.01). A reduced susceptibility to metronidazole was observed in 13 isolates that subsequently proved to be metronidazole-susceptible when, after thawing, they were retested using the agar dilution method. No reduced susceptibility to vancomycin was found. CONCLUSIONS: These results show the emergence of C. difficile ribotypes 027 and 176 with a predominance of ribotype 001 in Slovakia in 2016. Given that an almost homogeneous reduced susceptibility to moxifloxacin was detected in C. difficile isolates, this stresses the importance of reducing fluoroquinolone prescriptions in Slovak healthcare settings.


Assuntos
Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Clostridium difficile/classificação , Adolescente , Idoso , Antibacterianos/farmacologia , Clostridium difficile/efeitos dos fármacos , Clostridium difficile/genética , Clostridium difficile/isolamento & purificação , Feminino , Humanos , Incidência , Lactente , Masculino , Moxifloxacina/farmacologia , Ribotipagem , Eslováquia/epidemiologia
7.
BMC Cardiovasc Disord ; 19(1): 312, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31870305

RESUMO

BACKGROUND: Whipple's disease is a clinically relevant multi-system disorder that is often undiagnosed given its elusive nature. We present an atypical case of Whipple's disease involving pan-valvular endocarditis and constrictive pericarditis, requiring cardiac intervention. A literature review was also performed assessing the prevalence of atypical cases of Whipple's disease. CASE PRESENTATION: A previously healthy 56-year-old male presented with a four-year history of congestive heart failure with weight loss and fatigue. Notably, he had absent gastrointestinal symptoms. He went on to develop pan-valvular endocarditis and constrictive pericarditis requiring urgent cardiac surgery. A clinical diagnosis of Whipple's disease was suspected, prompting duodenal biopsy sampling which was unremarkable, Subsequently, Tropheryma whipplei was identified by 16S rDNA PCR on the cardiac valvular tissue. He underwent prolonged antibiotic therapy with recovery of symptoms. CONCLUSIONS: Our study reports the first known case of Whipple's disease involving pan-valvular endocarditis and constrictive pericarditis. A literature review also highlights this presentation of atypical Whipple's with limited gastrointestinal manifestations. Duodenal involvement was limited and the gold standard of biopsy was not contributory. We also highlight the Canadian epidemiology of the disease from 2012 to 2016 with an approximate 4% prevalence rate amongst submitted samples. Routine investigations for Whipple's disease, including duodenal biopsy, in this case may have missed the diagnosis. A high degree of suspicion was critical for diagnosis of unusual manifestations of Whipple's disease.


Assuntos
Endocardite Bacteriana/microbiologia , Doenças das Valvas Cardíacas/microbiologia , Miocardite/microbiologia , Pericardite Constritiva/microbiologia , Tropheryma/isolamento & purificação , Doença de Whipple/microbiologia , Antibacterianos/uso terapêutico , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/cirurgia , Insuficiência Cardíaca/microbiologia , Doenças das Valvas Cardíacas/diagnóstico , Doenças das Valvas Cardíacas/tratamento farmacológico , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Anuloplastia da Valva Mitral , Miocardite/diagnóstico , Miocardite/tratamento farmacológico , Pericardiectomia , Pericardite Constritiva/diagnóstico , Pericardite Constritiva/tratamento farmacológico , Pericardite Constritiva/cirurgia , Ribotipagem , Resultado do Tratamento , Tropheryma/genética , Doença de Whipple/diagnóstico , Doença de Whipple/tratamento farmacológico
8.
Anaerobe ; 60: 102106, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31655214

RESUMO

The molecular epidemiology and antimicrobial resistance of Clostridioides difficile were studied in South Korea in 2017 as part of a National Surveillance System. From February to May 2017, all non-duplicate isolates of C. difficile were recovered from patients who were suspected to have C. difficile infection and collected from 6 referral hospitals representing the 6 regions in South Korea. We performed PCRs for the toxin gene, PCR ribotyping, multilocus sequence typing (MLST), antimicrobial susceptibility testing by agar dilution according to the recommendations of the CLSI and detection of antimicrobial resistance genes such as ermB, catD, tetM, vanZ and nimR by PCR. Of 331 C. difficile isolates, 257 (77.6%) were toxigenic and the prevalence of strains producing binary toxin (CDT) was 5.1% (13/257). A total of 52 different ribotype (RT) patterns were found. RT018 was the most common (25.1% of all isolates), and RT014/020, RT002 and RT012 were also common. RT010 was most common non-toxigenic strain. MLST analysis of randomly selected 72 C. difficile isolates identified 46 sequence types (STs), of which three were new and not in the PubMLST library. There was a good correlation between MLST and RT as following: ST1 (RT027), ST8 (RT002), ST11 (RT078), ST17 (RT018), ST35 (RT046), ST37 (RT017), ST42 (RT106), ST53 (RT103), ST81 (RT369), and ST99 (RT070). All toxigenic isolates were susceptible to metronidazole and vancomycin (MIC ≤ 2 mg/L). For rifaximin, 24% of toxigenic isolates were resistant. Of randomly selected 106 toxigenic isolates, resistance rates for ampicillin, cefotetan, clindamycin, imipenem, chloramphenicol, tetracycline, and moxifloxacin were 48%, 46%, 64%, 54%, 0%, 6% and 52% respectively and frequencies of various resistance genes were 62.3% for ermB, 0.9% catD and 10.4% tetM. RTs018, 002, 017 and 369 showed high MICs to various antimicrobial agents and multi-drug resistance was common also.


Assuntos
Antibacterianos/farmacologia , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Clostridium difficile/efeitos dos fármacos , Clostridium difficile/genética , Adulto , Idoso , Antibacterianos/uso terapêutico , Toxinas Bacterianas/genética , Infecções por Clostridium/tratamento farmacológico , Clostridium difficile/classificação , Clostridium difficile/isolamento & purificação , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Vigilância em Saúde Pública , República da Coreia/epidemiologia , Ribotipagem
9.
mSphere ; 4(5)2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578248

RESUMO

Clostridium difficile infection (CDI) is a leading cause of hospital-acquired diarrhea. In recent decades, the emergence of the "hypervirulent" BI/NAP1/027 strains of C. difficile significantly increased the morbidity and mortality of CDI. The pathogenesis of CDI is primarily mediated by the action of two toxins, TcdA and TcdB, with TcdB being the major virulent factor in humans. In this report, we describe the engineering of a panel of designed ankyrin repeat proteins (DARPins) that potently neutralize TcdB from the BI/NAP1/027 strains (e.g., TcdBUK1). The most effective DARPin, D16, inhibits TcdBUK1 with a 50% effective concentration (EC50) of 0.5 nM, which is >66-fold lower than that of the FDA-approved anti-TcdB antibody bezlotoxumab (EC50, ∼33 nM). Competitive enzyme-linked immunosorbent assays (ELISAs) showed that D16 blocks interactions between TcdB and its receptor, chondroitin sulfate proteoglycan 4 (CSPG4). The dimeric DARPin U3D16, which pairs D16 with DARPin U3, a disrupter of the interaction of TcdB with Frizzled 1/2/7 receptor, exhibits 10-fold-to-20-fold-enhanced neutralization potency against TcdB from C. difficile strains VPI 10463 (laboratory strain) and M68 (CF/NAP9/017) but identical activity against TcdBUK1 relative to D16. Subsequent ELISAs revealed that TcdBUK1 did not significantly interact with Frizzled 1/2/7. Computation modeling revealed 4 key differences at the Frizzled 1/2/7 binding interface which are likely responsible for the significantly reduced binding affinity.IMPORTANCE We report the engineering and characterization of designed ankyrin proteins as potent neutralizers of TcdB toxin secreted by a hypervirulent ribotype 027 strain of Clostridium difficile We further show that although TcdB toxins from both ribotype 027 and VPI 10461 interact efficiently with TcdB receptors CSPG4 and Pvrl3, TcdB027 lacks significant ability to bind the only known physiologically relevant TcdB receptor, Frizzled 1/2/7.


Assuntos
Repetição de Anquirina , Proteínas de Bactérias/antagonistas & inibidores , Toxinas Bacterianas/antagonistas & inibidores , Clostridium difficile/classificação , Engenharia de Proteínas , Animais , Células CACO-2 , Chlorocebus aethiops , Humanos , Ribotipagem , Células Vero
10.
PLoS Biol ; 17(10): e3000379, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658249

RESUMO

Recent work has revealed that Clostridioides difficile, a major cause of nosocomial diarrheal disease, exhibits phenotypic heterogeneity within a clonal population as a result of phase variation. Many C. difficile strains representing multiple ribotypes develop two colony morphotypes, termed rough and smooth, but the biological implications of this phenomenon have not been explored. Here, we examine the molecular basis and physiological relevance of the distinct colony morphotypes produced by this bacterium. We show that C. difficile reversibly differentiates into rough and smooth colony morphologies and that bacteria derived from the isolates display discrete motility behaviors. We identified an atypical phase-variable signal transduction system consisting of a histidine kinase and two response regulators, named herein colony morphology regulators RST (CmrRST), which mediates the switch in colony morphology and motility behaviors. The CmrRST-regulated surface motility is independent of flagella and type IV pili, suggesting a novel mechanism of cell migration in C. difficile. Microscopic analysis of cell and colony structure indicates that CmrRST promotes the formation of elongated bacteria arranged in bundled chains, which may contribute to bacterial migration on surfaces. In a hamster model of acute C. difficile disease, the CmrRST system is required for disease development. Furthermore, we provide evidence that CmrRST phase varies during infection, suggesting that the intestinal environment impacts the proportion of CmrRST-expressing C. difficile. Our findings indicate that C. difficile employs phase variation of the CmrRST signal transduction system to generate phenotypic heterogeneity during infection, with concomitant effects on bacterial physiology and pathogenesis.


Assuntos
Proteínas de Bactérias/genética , Clostridium difficile/metabolismo , Regulação Bacteriana da Expressão Gênica , Histidina Quinase/genética , Transdução de Sinais/genética , Animais , Proteínas de Bactérias/metabolismo , Células Clonais , Infecções por Clostridium/microbiologia , Infecções por Clostridium/patologia , Clostridium difficile/genética , Clostridium difficile/patogenicidade , Clostridium difficile/ultraestrutura , Cricetulus , Modelos Animais de Doenças , Fímbrias Bacterianas/metabolismo , Fímbrias Bacterianas/ultraestrutura , Flagelos/metabolismo , Flagelos/ultraestrutura , Histidina Quinase/metabolismo , Humanos , Movimento , Fenótipo , Ribotipagem
11.
Anaerobe ; 60: 102107, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31647977

RESUMO

BACKGROUND: The optimal and practical laboratory diagnostic approach for detection of Clostridioides difficile to aid in the diagnosis of C. difficile infection (CDI) is controversial. A two-step algorithm with initial detection of glutamate dehydrogenase (GDH) or nucleic acid amplification test (NAAT) alone are recommended as a predominant method for C. difficile detection in developed countries. The aim of this study was to compare the performance of enzyme immunoassays (EIA) detecting toxins A and B, NAAT detecting the toxin B gene, and GDH compared to toxigenic culture (TC) for C. difficile as the gold standard, in patients prospectively and actively assessed with clinically significant diarrhea in 12 medical facilities in Japan. METHODS: A total of 650 stool specimens were collected from 566 patients with at least three diarrheal bowel movements (Bristol stool grade 6-7) in the preceding 24 h. EIA and GDH were performed at each hospital, and NAAT and toxigenic C. difficile culture with enriched media were performed at the National Institute of Infectious Diseases. All C. difficile isolates recovered were analyzed by PCR-ribotyping. RESULTS: Compared to TC, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of EIA were 41%, 96%, 75% and 84%, respectively, and for NAAT were 74%, 98%, 91%, and 92%, respectively. In 439 specimens tested with GDH, the sensitivity, specificity, PPV, and NPV were 73%, 87%, 65%, and 91%, and for an algorithm (GDH plus toxin EIA, arbitrated by NAAT) were 71%, 96%, 85%, and 91%, respectively. Among 157 isolates recovered, 75% of isolates corresponded to one of PCR-ribotypes (RTs) 002, 014, 018/018", and 369; RT027 was not isolated. No clear differences in the sensitivities of any of EIA, NAAT and GDH for four predominant RTs were found. CONCLUSION: The analytical sensitivities of NAAT and GDH-algorithm to detect toxigenic C. difficile in this study were lower than most previous reports. This study also found low PPV of EIAs. The optimal method to detect C. difficile or its toxins to assist in the diagnosis of CDI needs further investigation.


Assuntos
Técnicas Bacteriológicas , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/microbiologia , Clostridium difficile/genética , Toxinas Bacterianas/genética , Técnicas Bacteriológicas/métodos , Técnicas Bacteriológicas/normas , Infecções por Clostridium/epidemiologia , Clostridium difficile/classificação , Clostridium difficile/isolamento & purificação , Feminino , Humanos , Japão/epidemiologia , Masculino , Reação em Cadeia da Polimerase , Estudos Prospectivos , Ribotipagem , Sensibilidade e Especificidade
12.
Anaerobe ; 60: 102094, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31499177

RESUMO

It is known that antibiotic usage is associated with the development of Clostridioides difficile infection (CDI), especially clindamycin, third-generation cephalosporins, and fuoroquinolones. Antibiotic resistance rates to many antibiotics varies a lot by study. We performed a study focused on antibiotic resistance in clinical isolates of C. difficile from more widespread geographic regions across China. Of 319 C. difficile isolates tested against 11 antibiotics, 313 (98.1%) were resistant to at least one antibiotic. The highest rate of resistance was to ciprofloxacin, clindamycin, and erythromycin across all age groups, similar to previous studies. However, all isolates were susceptible to metronidazole and vancomycin. Overall the resistance rate to tested antibiotics was lower than other reports in China except for chloramphenicol and meropenem. Genotype ST37/RT017 in clade 4 was resistant to more antibiotics than other types. Unexpectedly, RT078 isolates in this study were susceptible to almost all tested antibiotics. In addition, the proportion of multi-drug resistant (MDR) isolates observed (17%) in this study was much lower than several European studies (up to 55%) and a previous study in China (78%). Although isolates from patients aged between 65 and 85 were more resistant to antibiotics in comparison to other age groups, MDR isolates were still detected in children below 2-years of age. The highest percentage of MDR isolates was determined in South China, an area that is most developed economically. The clade 4, RT017 (ST37) has been associated with outbreaks in Europe and North America and is responsible for most C. difficile infections (CDIs) in Asia. In addition, RT017 is often clindamycin and fluoroquinolone resistant. This study provided a relatively comprehensive description of antibiotic resistance of C. difficile in China, and further elucidates the epidemiology and antibiotic resistance of clinical isolates of C. difficile in China at a national level.


Assuntos
Antibacterianos/farmacologia , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Clostridium difficile/efeitos dos fármacos , Farmacorresistência Bacteriana , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Toxinas Bacterianas/genética , Criança , Pré-Escolar , China/epidemiologia , Clostridium difficile/classificação , Clostridium difficile/genética , Clostridium difficile/isolamento & purificação , Farmacorresistência Bacteriana Múltipla , Genótipo , Geografia Médica , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Vigilância em Saúde Pública , Ribotipagem , Adulto Jovem
13.
Biomedica ; 39(Supl. 2): 157-171, 2019 08 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31529842

RESUMO

Introduction: Inflammation in the gastric antrum caused by Helicobacter pylori increases the risk of duodenal ulcer while inflammation in the body generates atrophic gastritis and increased risk of gastric cancer. These inflammatory responses according to gastric topography could be explained by the composition of the gastric microbiota associated with H. pylori. Objective: To identify and compare the microbiota of the gastric antrum and body of individuals from two populations, one with high risk and one with low risk of gastric cancer from Nariño, Colombia. Materials and methods: Biopsies of the gastric antrum and body of patients with non-atrophic gastritis or metaplastic atrophic gastritis were included. The microbiota was defined by sequencing the 16S rRNA gene, V3-V4 region, (illumina-MiSeq™). The operational taxonomic units were classified using the BLASTn and RDPII databases. The differences among microbial populations were evaluated with the PERMANOVA and multivariate analyses. Results: The Epsilonproteobacteria class represented by H. pylori was more abundant in the antrum and body biopsies of individuals with metaplastic atrophic gastritis (>50%) while in individuals with non-atrophic gastritis it was 20 % and had greater metagenomic diversity. Helicobacter pylori infection significantly decreases the metagenomic diversity of the gastric antrum (p=0.005) compared to that of the body. Conclusions: The bacterial groups involved in the dysbiosis can colonize both topographic regions of the stomach, regardless of the sectorized inflammation responses. Helicobacter pylori infection associated with the gastric microbiota is related to its localization in the stomach, the type of lesion, and the population at risk of gastric cancer, which suggests its importance in microbial dysbiosis and gastric disease.


Assuntos
Gastrite/microbiologia , Microbioma Gastrointestinal , Neoplasias Gástricas/epidemiologia , Estômago/microbiologia , Adulto , Idoso , Colômbia/epidemiologia , Feminino , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastrite/epidemiologia , Gastrite Atrófica/epidemiologia , Gastrite Atrófica/microbiologia , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Metaplasia , Pessoa de Meia-Idade , Antro Pilórico/microbiologia , Ribotipagem , Risco
14.
Biomedica ; 39: 10-18, 2019 05 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31529845

RESUMO

Melioidosis is an infectious disease caused by Burkholderia pseudomallei whose clinical diagnosis can be difficult due not only to its varied clinical presentation but also to the difficulties in the microbiological diagnosis.Thus, it may be necessary to use molecular techniques for its proper identification once it is suspected. There are few antibiotics available for the treatment of this disease, which must be used over a long period of time. Although it is known to be endemic in Thailand, Malaysia, Singapore, Vietnam, and Australia, in Colombia there are few reported cases. We describe a case of melioidosis in the northern region of Colombia. Additionally, we review its clinical characteristics and treatment and we describe the local epidemiology of this disease.


Assuntos
Melioidose/epidemiologia , Amputação , Antibacterianos/uso terapêutico , Burkholderia pseudomallei/isolamento & purificação , Colômbia/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Doenças do Pé/cirurgia , Humanos , Hospedeiro Imunocomprometido , Falência Renal Crônica/complicações , Masculino , Melioidose/diagnóstico , Melioidose/tratamento farmacológico , Pessoa de Meia-Idade , Cooperação do Paciente , Recidiva , Ribotipagem , Dedos do Pé/microbiologia , Dedos do Pé/cirurgia , Infecções Urinárias/diagnóstico , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia
15.
Int J Med Microbiol ; 309(8): 151355, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563331

RESUMO

Staphylococcus petrasii is recently described coagulase negative staphylococcal species and an opportunistic human pathogen, still often misidentified in clinical specimens. Four subspecies are distinguished in S. petrasii by polyphasic taxonomical analyses, however a comparative study has still not been done on the majority of isolates and their genome properties have not yet been thoroughly analysed. Here, we describe the phenotypic and genotypic characteristics of 65 isolates and the results of de novo sequencing, whole genome assembly and annotation of draft genomes of five strains. The strains were identified by MALDI-TOF mass spectrometry to the species level and the majority of the strains were identified to the subspecies level by fingerprinting methods, (GTG)5 repetitive PCR and ribotyping. Macrorestriction profiling by pulsed-field gel electrophoresis was confirmed to be a suitable strain typing method. Comparative genomics revealed the presence of new mobile genetic elements carrying antimicrobial resistance factors such as staphylococcal cassette chromosome (SCC) mec, transposones, phage-inducible genomic islands, and plasmids. Their mosaic structure and similarity across coagulase-negative staphylococci and Staphylococcus aureus suggest the possible exchange of these elements. Numerous putative virulence factors such as adhesins, autolysins, exoenzymes, capsule formation genes, immunomodulators, the phage-associated sasX gene, and SCC-associated spermidine N-acetyltransferase gene, pseudouridine and sorbitol utilization operons might explain clinical manifestations of S. petrasii isolates. The increasing recovery of S. petrasii isolates from human clinical material, the multi-drug resistance including methicillin resistance of S. petrasii subsp. jettensis strains, and virulence factors homologous to other pathogenic staphylococci demonstrate the importance of the species in human disease.


Assuntos
Genoma Bacteriano , Sequências Repetitivas Dispersas , Staphylococcus/genética , Fatores de Virulência/genética , Técnicas de Tipagem Bacteriana , Eletroforese em Gel de Campo Pulsado , Genômica , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Fenótipo , Ribotipagem , Staphylococcus/classificação , Staphylococcus/patogenicidade
16.
Anaerobe ; 60: 102087, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31419487

RESUMO

The prevalence of Clostridioides difficile PCR-ribotype (RT) 018 is low in Europe but variations are observed across countries. We report here the first RT 018-related outbreak in France that took place in 4 geriatric units (GU) in Strasbourg, France. From January to December 2017, 38 patients were diagnosed with C. difficile infection (CDI). Strains were first characterized by PCR ribotyping: 19 out of 38 (50%) strains belonged to RT 018. These strains as well as 12 RT 018 isolated in other French healthcare facilities and 2 strains of RT 018 isolated in the GU in 2015 were characterized by multi locus variable-number tandem repeat (VNTR) analysis (MLVA), whole genome multi locus sequence typing (wgMLST) and core genome single nucleotide polymorphism typing (cgSNP). The MLVA indicated that 15 out of 19 epidemic strains of RT 018 were included in 2 Clonal Complexes (CC). Four RT 018 strains from the outbreak did not belong to the CC. The wgMLST and cgSNP typing analysis revealed a single CC that included 19 strains from the geriatric unit (17 from GU in 2017 and 2 from GU in 2015) and 4 strains (33%) from other healthcare facilities (HCF). Our results suggest that a specific RT 018 clone has spread in the geriatric unit and has evolved slowly over time. MLVA, wgMLST and cgSNP typing results provided fairly consistent information but wgMLST and cgSNP typing better separated epidemic strains from non-epidemic strains. Compared to wgMLST, the cgSNP typing did not provide additional information.


Assuntos
Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Clostridium difficile/classificação , Clostridium difficile/genética , DNA Bacteriano , Surtos de Doenças , Genoma Bacteriano , Repetições Minissatélites , Antibacterianos/farmacologia , Toxinas Bacterianas/genética , Clostridium difficile/efeitos dos fármacos , Genômica/métodos , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Ribotipagem
17.
Anaerobe ; 60: 102086, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31404682

RESUMO

There have been few available data that presented a direct comparison between polymerase chain reaction ribotype (RT) distribution of Clostridioides difficile strains from C. difficile infection (CDI) and colonization. To understand the epidemiology of CDI in a hospital setting, we compared RTs of C. difficile strains from hospital-acquired CDI (HA-CDI) and toxigenic colonization and from community-acquired CDI (CA-CDI) and non-toxigenic colonization using the stool samples submitted for C. difficile cultures at an institution during 2009, 2012, and 2014. Overall, 721 C. difficile strains were identified from 607 patients. Among them, 450 (62.4%) were HA-CDI, 20 (2.8%) were CA-CDI, 126 (17.5%) were toxigenic colonization, and 125 (17.3%) were non-toxigenic colonization. RT018, RT017, RT002, RT015, and RT001 isolates were the most prevalent RTs in HA-CDI, and they comprised 74.9% of the total HA-CDI isolates but accounted for 60.4% of isolates from toxigenic colonization. In total, 32 strain compromising 18 RTs from HA-CDI (7.1%) were not seen among the toxigenic colonization group, and 3 RTs with 5 strains from toxigenic colonization were not seen among the HA-CDI group. The distribution of RTs was the most diverse in CA-CDI and the least diverse in HA-CDI. Although 5 RT strains, which were prevalent in HA-CDI, comprised 40% of CA-CDI, 5 isolates (25%) revealed unknown RTs, which were uncommon in HA-CDI or toxigenic colonization. In 12 patients with both episodes of CDI and toxigenic colonization, 8 had 2 isolates with different RTs and 4 had isolates with identical RTs. In conclusion, although RT017 and RT018 were the most common in HA-CDI and toxigenic colonization, C. difficile strains from toxigenic colonization were more diverse than those from HA-CDI.


Assuntos
Infecções por Clostridium/microbiologia , Clostridium difficile/genética , Clostridium difficile/metabolismo , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Ribotipagem , Idoso , Toxinas Bacterianas/genética , Infecções por Clostridium/epidemiologia , Clostridium difficile/classificação , Clostridium difficile/isolamento & purificação , Infecções Comunitárias Adquiridas/epidemiologia , Comorbidade , Infecção Hospitalar/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
18.
J Med Microbiol ; 68(10): 1445-1454, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31429817

RESUMO

Purpose. Clostridium difficile spores are extremely resilient to high temperatures. Sublethal temperatures are associated with the 'reactivation' of dormant spores, and are utilized to maximize C. difficile spore recovery. Spore eradication is of vital importance to the food industry. The current study seeks to elucidate the transient and persisting effects of heating C. difficile spores at various temperatures.Methods. Spores of five C. difficile strains of different ribotypes (001, 015, 020, 027 and 078) were heated at 50, 60 and 70-80 °C for 60 min in phosphate-buffered saline (PBS) and enumerated at 0, 15, 30, 45 and 60 min. GInaFiT was used to model the kinetics of spore inactivation. In subsequent experiments, spores were transferred to enriched brain heart infusion (BHI) broths after 10 min of 80 °C heat treatment in PBS; samples were enumerated at 90 min and 24 h.Results. The spores of all strains demonstrated log-linear inactivation with tailing when heated for 60 min at 80 °C [(x̄=7.54±0.04 log10 vs 4.72±0.09 log10 colony-forming units (c.f.u.) ml- 1; P<0.001]. At 70 °C, all strains except 078 exhibited substantial decline in recovery over 60 min. Interestingly, 50 °C heat treatment had an inhibitory effect on 078 spore recovery at 0 vs 60 min (7.61±0.06 log10 c.f.u. ml- 1 vs 6.13±0.05 log10 c.f.u. ml- 1; P<0.001). Heating at 70/80 °C inhibited the initial germination and outgrowth of both newly produced and aged spores in enriched broths. This inhibition appeared to be transient; after 24 h vegetative counts were higher in heat-treated vs non-heat-treated spores (x̄=7.65±0.04 log10 c.f.u. ml- 1 vs 6.79±0.06 log10 c.f.u. ml- 1; P<0.001).Conclusions. The 078 spores were more resistant to the inhibitory effects of higher temperatures. Heat initially inhibits spore germination, but the subsequent outgrowth of vegetative populations accelerates after the initial inhibitory period.


Assuntos
Clostridium difficile/crescimento & desenvolvimento , Esporos Bacterianos/química , Clostridium difficile/química , Clostridium difficile/classificação , Clostridium difficile/fisiologia , Temperatura Alta , Humanos , Cinética , Viabilidade Microbiana , Ribotipagem , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/fisiologia
20.
Anaerobe ; 60: 102083, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31377188

RESUMO

The relevance of large clostridial toxin-negative, binary toxin-producing (A-B-CDT+) Clostridium difficile strains in human infection is still controversial. In this study, we investigated putative virulence traits that may contribute to the role of A-B-CDT+C. difficile strains in idiopathic diarrhea. Phenotypic assays were conducted on 148 strains of C. difficile comprising 10 different A-B-CDT+C. difficile ribotypes (RTs): 033, 238, 239, 288, 585, 586, QX143, QX444, QX521 and QX629. A subset of these isolates (n = 53) was whole-genome sequenced to identify genetic loci associated with virulence and survival. Motility studies showed that with the exception of RT 239 all RTs tested were non-motile. C. difficile RTs 033 and 288 had deletions in the F2 and F3 regions of their flagella operon while the F2 region was absent from strains of RTs 238, 585, 586, QX143, QX444, QX521 and QX629. The flagellin and flagella cap genes, fliC and fliD, respectively, involved in adherence and host colonization, were conserved in all strains, including reference strains. All A-B-CDT+C. difficile strains produced at least three extracellular enzymes (deoxyribonuclease, esterase and mucinase) indicating that these are important extracellular proteins. The toxicity of A-B-CDT+C. difficile strains in Vero cells was confirmed, however, pathogenicity was not demonstrated in a mouse model of disease. Despite successful colonization by most strains, there was no evidence of disease in mice. This study provides the first in-depth analysis of A-B-CDT+C. difficile strains and contributes to the current limited knowledge of these strains as a cause of C. difficile infection.


Assuntos
Toxinas Bacterianas/genética , Infecções por Clostridium/microbiologia , Clostridium difficile/genética , Fatores de Virulência/genética , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/biossíntese , Clostridium difficile/classificação , Clostridium difficile/patogenicidade , Biologia Computacional , Modelos Animais de Doenças , Humanos , Hidrólise , Camundongos , Proteômica , Ribotipagem , Virulência , Fatores de Virulência/biossíntese
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