RESUMO
BACKGROUND: Geographic and temporal trends in the distribution of PCR ribotypes for Clostridioides difficile associated diarrheal isolates obtained in the United States (US) are changing. As part of a US national surveillance program of C. difficile susceptibility to fidaxomicin, we quantified the distribution of PCR ribotypes of stool isolates collected from 2011 to 2016. METHODS: C. difficile isolates or C. difficile toxin + stools from patients with C. difficile infection (CDI) were submitted for testing to Tufts Medical Center from 6 geographically distinct medical centers. Following isolation and confirmation as C. difficile, approximately 35% of the isolates were randomly sampled, stratified by center, for PCR ribotyping by capillary gel electrophoresis. Toxin gene profiling was performed on all isolates. RESULTS: 939 isolates from a total of 2814 (33.4%) isolated over the 6 years were analyzed. Seventy unique ribotypes were observed, including 19 ribotypes observed 10 or more times. Sixteen ribotypes were not previously observed in our data base. Ribotype 027 declined by more than 60% over the 6 years of the survey from 35.3% to 13.1% (pâ¯<â¯0.001). Ribotype 106 was the most common in 2016, followed by 027 and 014-020. There were strong correlations between 027 and binary toxin with the 18 base pair deletion of tcdC and ribotype 078-126 had 100% concordance with the previously described tcdC 39 base pair deletion. CONCLUSIONS: The frequency of ribotypes in the US has changed with a marked decline in 027. Each of the geographical areas had variations which differed from each other, but collectively, these results suggest that the changing epidemiology of C. difficile in the US is consistent with what is being seen in Europe. Continued surveillance and monitoring of changes in ribotype distributions of C. difficile are warranted.
Assuntos
Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/epidemiologia , Ribotipagem , Toxinas Bacterianas/genética , Técnicas de Tipagem Bacteriana/métodos , Diarreia/epidemiologia , Europa (Continente)/epidemiologia , Fezes/microbiologia , Genes Bacterianos , Humanos , RNA Ribossômico/genética , Estados Unidos/epidemiologiaRESUMO
A variant of the modified carbapenem inactivation method (mCIM) was developed to detect carbapenemase activity directly from positive blood culture broths. The method, termed "Blood-mCIM," was evaluated using Bactec blood culture bottles (Becton, Dickinson and Company, Franklin Lakes, NJ) inoculated with 27 different carbapenemase-producing Enterobacteriaceae (CPE) isolates and 34 different non-CPE isolates. The assay was positive for all blood culture broths inoculated with CPE isolates and negative for all blood culture broths inoculated with non-CPE isolates, corresponding to a diagnostic sensitivity and specificity of 100%, respectively. This assay is inexpensive using "off the shelf" reagents, does not require centrifugation or mechanical lysis, and can be readily implemented in any clinical microbiology laboratory. The Blood-mCIM should facilitate expedient administration of antimicrobial therapy targeted toward CPE bloodstream infections and assist infection control and public health surveillance.
Assuntos
Proteínas de Bactérias/genética , Hemocultura/métodos , Enterobacteriáceas Resistentes a Carbapenêmicos/enzimologia , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Carbapenêmicos/metabolismo , Fenótipo , beta-Lactamases/genética , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Carbapenêmicos/farmacologia , Infecções por Enterobacteriaceae/diagnóstico , Infecções por Enterobacteriaceae/microbiologia , Humanos , Inativação Metabólica , Testes de Sensibilidade Microbiana , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
In 2011, we initiated a sentinel surveillance network to assess changes in Clostridioides (formerly Clostridium) difficile antimicrobial susceptibility to fidaxomicin from 6 geographically dispersed medical centers in the United States. This report summarizes data from 2013 to 2016. C. difficile isolates or toxin-positive stools from patients were referred to a central laboratory. Antimicrobial susceptibility was determined by agar dilution. CLSI, EUCAST, or FDA breakpoints were used, where applicable. Toxin gene profiles were characterized by multiplex PCR on each isolate. A random sample of approximately 40% of isolates, stratified by institution and year, was typed by restriction endonuclease analysis (REA). Among 1,889 isolates from 2013 to 2016, the fidaxomicin MIC90 was 0.5 µg/ml; all isolates were inhibited at ≤1 µg/ml. There were decreases in metronidazole and vancomycin MICs over time. Clindamycin resistance remained unchanged (27.3%). An increase in imipenem resistance was observed. By 2015 to 2016, moxifloxacin resistance decreased in all centers. The proportion of BI isolates decreased from 25.5% in 2011 to 2012 to 12.8% in 2015 to 2016 (P < 0.001). The BI REA group correlated with moxifloxacin resistance (BI 84% resistant versus non-BI 12.5% resistant). Fidaxomicin MICs have not changed among C. difficile isolates of U.S. origin over 5 years post licensure. There has been an overall decrease in MICs for vancomycin, metronidazole, moxifloxacin, and rifampin and an increase in isolates resistant to imipenem. Moxifloxacin resistance remained high among the BI REA group, but the proportion of BI isolates has decreased. Continued geographic variations in REA groups and antimicrobial resistance persist.
Assuntos
Antibacterianos/farmacologia , Clostridioides difficile/efeitos dos fármacos , Infecções por Clostridium/microbiologia , Diarreia/microbiologia , Fidaxomicina/farmacologia , ADP Ribose Transferases/genética , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Clindamicina/farmacologia , Clostridioides difficile/genética , Clostridioides difficile/isolamento & purificação , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Enterotoxinas/genética , Humanos , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Proibitinas , Vigilância de Evento Sentinela , Estados UnidosRESUMO
The increase in the prevalence and impact of infections caused by carbapenemase-producing Enterobacteriaceae is a global health concern. Therefore, rapid and accurate methods to detect these organisms in any clinical microbiology laboratory, including those in resource-limited settings, are essential to prevent and contain their spread. It is also important to differentiate between serine- and metal-dependent carbapenemases elaborated by carbapenemase-producing isolates for epidemiologic, infection control and prevention, and therapeutic purposes. Here, we describe the development and evaluation of the EDTA-modified carbapenem inactivation method (eCIM), an assay for discriminating between serine- and metal-dependent (i.e., metallo-ß-lactamases [MBLs]) carbapenemases when used in conjunction with the modified carbapenem inactivation method (mCIM). The eCIM had an overall sensitivity and specificity of 100% and was adopted by the Clinical and Laboratory Standards Institute as a method to use in combination with the mCIM to identify MBL-producing Enterobacteriaceae.
Assuntos
Bioensaio/métodos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Carbapenêmicos/química , Ácido Edético/química , beta-Lactamases/classificação , Antibacterianos/química , Bioensaio/normas , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Metais , Testes de Sensibilidade Microbiana , Fenótipo , Sensibilidade e Especificidade , Serina , beta-Lactamases/isolamento & purificaçãoRESUMO
The susceptibility trends for Bacteroides fragilis and related species against various antibiotics were determined using data from 3 years of surveillance (2010-2012) on 779 isolates referred by 7 medical centers. The antibiotic test panel included imipenem, ertapenem, meropenem, ampicillin-sulbactam, piperacillin-tazobactam, cefoxitin, clindamycin, moxifloxacin, tigecycline, linezolid, chloramphenicol and . MICs were determined using the agar dilution CLSI reference method. Carbapenem resistance remained low (range 1.1%-2.5%) and unchanged from 2008 to 9 through 2010-2012. Resistance also remained low to the beta-lactam/beta-lactamase inhibitor combinations (1.1%-4.4%). While resistance to clindamycin and moxifloxacin remained high; rates were lower for B. fragilis in 2010-12 (24% and 19% respectively) compared to the earlier time frame of 2008-9 (29% and 35% respectively for the earlier time frame). There were notable species and resistance associations which have been demonstrated previously. No resistance to metronidazole or chloramphenicol resistance was seen. These data demonstrate the continued variability in resistance among Bacteroides and Parabacteroides species, but do demonstrate that carbapenems and beta-lactam/beta-lactamase inhibitor combinations remain very active throughout the United States.
Assuntos
Anti-Infecciosos/farmacologia , Infecções por Bacteroides/tratamento farmacológico , Bacteroidetes/efeitos dos fármacos , Carbapenêmicos/farmacologia , Resistência Microbiana a Medicamentos , Inibidores de beta-Lactamases/farmacologia , Bacteroides/efeitos dos fármacos , Infecções por Bacteroides/microbiologia , Bacteroides fragilis/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Ácido Penicilânico/análogos & derivados , Ácido Penicilânico/farmacologia , Piperacilina/farmacologia , Combinação Piperacilina e Tazobactam , Estados UnidosRESUMO
Previous studies reported decreased mortality in patients with carbapenemase-producing Klebsiella pneumoniae bloodstream infections (BSIs) treated with combination therapy but included carbapenem-susceptible and -intermediate isolates, as per revised CLSI breakpoints. Here, we assessed outcomes in patients with BSIs caused by phenotypically carbapenem-resistant K. pneumoniae (CRKP) according to the number of in vitro active agents received and whether an extended-spectrum beta-lactam (BL) antibiotic, including meropenem, or an extended-spectrum cephalosporin was administered. We retrospectively reviewed CRKP BSIs at two New York City hospitals from 2006 to 2013, where all isolates had meropenem or imipenem MICs of ≥4 µg/ml. Univariate and multivariable models were created to identify factors associated with mortality. Of 141 CRKP BSI episodes, 23% were treated with a single active agent (SAA), 26% were treated with an SAA plus BL, 28% were treated with multiple active agents (MAA), and 23% were treated with MAA plus BL. Ninety percent of isolates had meropenem MICs of ≥16 µg/ml. Thirty-day mortality was 33% overall and did not significantly differ across the four treatment groups in a multivariable model (P = 0.4); mortality was significantly associated with a Pitt bacteremia score of ≥4 (odds ratio [OR], 7.7; 95% confidence interval [CI], 3.2 to 18.1; P = 0.1), and immunosuppression was protective (OR, 0.4; 95% CI, 0.2 to 1.0; P = 0.04). Individual treatment characteristics were also not significantly associated with outcome, including use of SAAs versus MAA (26% versus 38%, P = 0.1) or BL versus no BL (26% versus 39%, P = 0.1). In summary, in patients with CRKP BSIs caused by isolates with high carbapenem MICs, the role of combination therapy remains unclear, highlighting the need for prospective studies to identify optimal treatment regimens.
Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Imipenem/uso terapêutico , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Tienamicinas/uso terapêutico , Resistência beta-Lactâmica , Idoso , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Bacteriemia/patologia , Cefalosporinas/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/mortalidade , Infecções por Klebsiella/patologia , Klebsiella pneumoniae/crescimento & desenvolvimento , Klebsiella pneumoniae/patogenicidade , Masculino , Meropeném , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
In 2011 a surveillance study for the susceptibility to fidaxomicin and epidemiology of Clostridium difficile isolates in the United States was undertaken in seven geographically dispersed medical centers. This report encompasses baseline surveillance in 2011 and 2012 on 925 isolates. A convenience sample of C. difficile isolates or toxin positive stools from patients were referred to a central laboratory. Antimicrobial susceptibility was determined by agar dilution (CLSI M11-A8). Clinical and Laboratory Standards Institute (CLSI), Food and Drug Administration, or European Union of Clinical Antimicrobial Susceptibility Testing (EUCAST) breakpoints were applied where applicable. Toxin gene profiles were characterized by multiplex PCR on each isolate. A random sample of 322 strains, stratified by institution, underwent restriction endonuclease analysis (REA). The fidaxomicin MIC90 was 0.5 µg/ml for all isolates regardless of REA type or toxin gene profile, and all isolates were inhibited at ≤1.0 µg/ml. By REA typing, BI strains represented 25.5% of the isolates. The toxin gene profile of tcdA, tcdB, and cdtA/B positive with a tcdC 18-bp deletion correlated with BI REA group. Moxifloxacin and clindamycin resistance was increased among either BI or binary toxin-positive isolates. Metronidazole and vancomycin showed reduced susceptibility (EUCAST criteria) in these isolates. Geographic variations in susceptibility, REA group and binary toxin gene presence were observed. Fidaxomicin activity against C. difficile isolated in a national surveillance study did not change more than 1 year after licensure. This analysis provides baseline results for future comparisons.
Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Clostridioides difficile/efeitos dos fármacos , Diarreia/epidemiologia , Enterocolite Pseudomembranosa/epidemiologia , Genes Bacterianos , Vigilância de Evento Sentinela , Toxinas Bacterianas/genética , Toxinas Bacterianas/imunologia , Toxinas Bacterianas/isolamento & purificação , Clindamicina/farmacologia , Clostridioides difficile/genética , Clostridioides difficile/isolamento & purificação , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Farmacorresistência Bacteriana/genética , Enterocolite Pseudomembranosa/tratamento farmacológico , Enterocolite Pseudomembranosa/microbiologia , Fidaxomicina , Fluoroquinolonas/farmacologia , Humanos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana , Moxifloxacina , Reação em Cadeia da Polimerase Multiplex , Proibitinas , Estados Unidos/epidemiologia , Vancomicina/farmacologiaRESUMO
BACKGROUND: Human rhinoviruses (HRVs) are a common cause of upper respiratory infection (URI) in hematopoietic stem cell transplant (HSCT) recipients; yet, their role in lower respiratory illness is not well understood. METHODS: We performed a retrospective chart review of HSCT recipients with HRV infection from the time molecular detection methods were implemented at our institution in 2008. Factors associated with proven or possible HRV pneumonia at the first HRV detection were evaluated by univariate and multivariate analysis. We then characterized all episodes of proven and possible HRV pneumonia from the initial HRV infection through a 1-year follow-up period. RESULTS: Between 2008 and 2011, 63 HSCT recipients had ≥1 documented HRV infections. At first HRV detection, 36 (57%) patients had HRV URI and 27 (43%) had proven or possible HRV pneumonia; in multivariate analysis, hypoalbuminemia (odds ratio [OR] 9.5, 95% confidence interval [CI] 1.3-71.7; P = 0.03) and isolation of respiratory co-pathogen(s) (OR 24.2, 95% CI 2.0-288.4; P = 0.01) were independently associated with pneumonia. During the study period, 22 patients had 25 episodes of proven HRV pneumonia. Fever (60%), cough (92%), sputum production (61%), and dyspnea (60%) were common symptoms. Fifteen (60%) episodes demonstrated bacterial (n = 7), fungal (n = 5), or viral (n = 3) co-infection. Among the remaining 10 (40%) cases of HRV monoinfection, patients' oxygen saturations ranged from 80% to 97% on ambient air, and computed tomography scans showed peribronchiolar, patchy, ground glass infiltrates. CONCLUSIONS: HRV pneumonia is relatively common after HSCT and frequently accompanied by bacterial co-infection. As use of molecular assays for respiratory viral diagnosis becomes widespread, HRV will be increasingly recognized as a significant cause of pneumonia in immunocompromised hosts.
Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecções por Picornaviridae/epidemiologia , Pneumonia Viral/epidemiologia , Rhinovirus/isolamento & purificação , Adulto , Idoso , Bactérias/isolamento & purificação , Infecções Bacterianas/complicações , Infecções Bacterianas/microbiologia , Coinfecção , Feminino , Fungos/isolamento & purificação , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Micoses/complicações , Micoses/microbiologia , Infecções por Picornaviridae/complicações , Infecções por Picornaviridae/mortalidade , Infecções por Picornaviridae/virologia , Pneumonia Viral/complicações , Pneumonia Viral/mortalidade , Infecções Respiratórias/complicações , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/mortalidade , Infecções Respiratórias/virologia , Estudos Retrospectivos , Estações do Ano , Adulto JovemRESUMO
A total of 142 stool specimens were evaluated for vancomycin-resistant enterococcus (VRE). Twenty-four-hour sensitivities and specificities, respectively, were 98% and 95% for Spectra VRE chromogenic agar (Remel, Lenexa, KS), 86% and 92% for bile esculin azide with vancomycin (BEAV; Remel), and 96.5% and 92% for Campylobacter agar (CAMPY; Remel). Spectra VRE and CAMPY are significantly more sensitive at 24 h than BEAV.
Assuntos
Técnicas Bacteriológicas/métodos , Meios de Cultura/química , Enterococcus/isolamento & purificação , Fezes/microbiologia , Infecções por Bactérias Gram-Positivas/diagnóstico , Resistência a Vancomicina , Ágar , Antibacterianos/farmacologia , Azidas/farmacologia , Bile/metabolismo , Compostos Cromogênicos/metabolismo , Enterococcus/efeitos dos fármacos , Esculina/metabolismo , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Sensibilidade e Especificidade , Vancomicina/farmacologiaRESUMO
OBJECTIVES: This study examined Klebsiella pneumoniae clinical isolates and their bla(KPC) plasmids to determine potential relatedness of the isolates and their plasmids harbouring carbapenem resistance mechanisms. METHODS: K. pneumoniae carbapenemase (KPC)-producing K. pneumoniae from New York City (NYC) (nâ=â19) and Toronto (nâ=â2) were typed by PFGE and multilocus sequence typing (MLST). bla(KPC)-harbouring plasmids were transformed into Escherichia coli DH10B(TM), restricted using EcoRI and analysed for bla content and replicon (rep) type. Susceptibility profiles for clinical and transformed strains were determined by automated microbroth dilution using CLSI breakpoints. Outer membrane protein (OMP) genes were analysed by sequencing of ompk35 and ompk36. RESULTS: PFGE analysis identified 17 related strains (≥ 80% similarity; 11 KPC-2, 6 KPC-3) where ST258 was the dominant clonal type. All clinical isolates contained both bla(SHV) and bla(TEM-1) and, with the exception of one isolate, were multidrug resistant (MDR). Transformed KPC plasmids (nâ=â21) carried TEM-1 (nâ=â18) and were MDR (nâ=â5). Three plasmid clusters, repFIIA (nâ=â10), repR (nâ=â3) and an unknown type (nâ=â3), were observed. repFllA plasmids were observed from both NYC and Toronto strains. OMP gene analysis revealed premature stop codons in ompk35 and numerous deletions and insertions in ompk36. CONCLUSIONS: The dissemination of bla(KPC) is due both to carriage of similar KPC-harbouring plasmids within genetically distinct K. pneumoniae and to clonal spread of K. pneumoniae with unrelated KPC plasmids.
Assuntos
Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Plasmídeos , Resistência beta-Lactâmica , beta-Lactamases/genética , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Técnicas de Tipagem Bacteriana , Canadá , Carbapenêmicos/farmacologia , Eletroforese em Gel de Campo Pulsado , Feminino , Transferência Genética Horizontal , Humanos , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem Molecular , Tipagem de Sequências Multilocus , Cidade de Nova Iorque , Transformação BacterianaRESUMO
The susceptibility trends for the species of the Bacteroides fragilis group against various antibiotics from 1997 to 2004 were determined by using data for 5,225 isolates referred by 10 medical centers. The antibiotic test panel included ertapenem, imipenem, meropenem, ampicillin-sulbactam, piperacillin-tazobactam, cefoxitin, clindamycin, moxifloxacin, tigecycline, chloramphenicol, and metronidazole. From 1997 to 2004 there were decreases in the geometric mean (GM) MICs of imipenem, meropenem, piperacillin-tazobactam, and cefoxitin for many of the species within the group. B. distasonis showed the highest rates of resistance to most of the beta-lactams. B. fragilis, B. ovatus, and B. thetaiotaomicron showed significantly higher GM MICs and rates of resistance to clindamycin over time. The rate of resistance to moxifloxacin of B. vulgatus was very high (MIC range for the 8-year study period, 38% to 66%). B. fragilis, B. ovatus, and B. distasonis and other Bacteroides spp. exhibited significant increases in the rates of resistance to moxifloxacin over the 8 years. Resistance rates and GM MICs for tigecycline were low and stable during the 5-year period over which this agent was studied. All isolates were susceptible to chloramphenicol (MICs < 16 microg/ml). In 2002, one isolate resistant to metronidazole (MIC = 64 microg/ml) was noted. These data indicate changes in susceptibility over time; surprisingly, some antimicrobial agents are more active now than they were 5 years ago.
Assuntos
Antibacterianos/farmacologia , Bacteroides fragilis/efeitos dos fármacos , Bacteroides/efeitos dos fármacos , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana , Fatores de Tempo , Estados UnidosRESUMO
Antibiotic resistance is a global health priority. Major defenses for Gram-negative bacteria are beta-lactamase enzymes, which have co-evolved with the development and increasing utilization of new antibiotics. Bacteria harboring the plasmid-mediated AmpC enzymes are increasingly prevalent among adult patients, but have not previously been reported in neonates. Early-onset neonatal meningitis caused by an AmpC beta-lactamase-producing Escherichia coli is described for the first time; the plasmid was identified as a transferable CMY-2 family beta-lactamase. Limited experience with newer antibiotics and pharmacokinetics in neonates presents a therapeutic challenge. Currently, there are no Clinical Laboratory Standards Institute (CLSI) recommendations for detecting AmpC nor is the optimal treatment for AmpC-producing organisms known. Thus, it is imperative that clinicians have a high index of suspicion when antimicrobial susceptibility patterns are inconsistent. Development of better microbiology screening tests to rapidly detect resistance is essential. Additionally, pharmacokinetic studies with newer antibiotics in neonates are warranted.
Assuntos
Proteínas de Bactérias/biossíntese , Doenças em Gêmeos , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/tratamento farmacológico , Escherichia coli/enzimologia , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/tratamento farmacológico , beta-Lactamases/biossíntese , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Humanos , Recém-Nascido , Meningites Bacterianas/microbiologiaRESUMO
Few data exist on the distribution of Streptococcus pneumoniae serotypes in many countries and in non-invasive disease overall. Here, data are presented from 772 paediatric isolates from children with community-acquired respiratory tract infections isolated from the PROTEKT global surveillance study during 1999-2000. Overall, 60.0 % of isolates were covered by the 7-valent pneumococcal vaccine formulation (PCV7), with greater coverage in the USA compared with Europe (69.6 vs 55.5 %, P = 0.014). Geographically dispersed clones of serogroups 3, 11 and 15 accounted for most of the isolates outside PCV7 coverage. Overall, macrolide, penicillin and cotrimoxazole non-susceptibility rates were high; however, all isolates were susceptible to telithromycin. Although only 7.4 % of isolates were resistant to amoxycillin/clavulanate, a higher prevalence of resistance was found in isolates from the USA and South Korea. This study shows the feasibility and importance of serotyping antibiotic surveillance study isolates and the potential of telithromycin as an important option for empiric therapy.
Assuntos
Cetolídeos/farmacologia , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/efeitos dos fármacos , Adolescente , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Sangue/microbiologia , Líquido da Lavagem Broncoalveolar/microbiologia , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , Farmacorresistência Bacteriana , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Lactente , Recém-Nascido , Vacinas Meningocócicas/imunologia , Testes de Sensibilidade Microbiana , Nasofaringe/microbiologia , Vacinas Pneumocócicas/imunologia , Infecções Respiratórias/microbiologia , Sorotipagem , Escarro/microbiologia , Streptococcus pneumoniae/isolamento & purificaçãoAssuntos
Farmacorresistência Bacteriana Múltipla , Cetolídeos/farmacologia , Resistência a Meticilina , Staphylococcus aureus/efeitos dos fármacos , Adolescente , Idoso , Antibacterianos/farmacologia , Criança , Pré-Escolar , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Feminino , Humanos , Cooperação Internacional , Estudos Longitudinais , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/isolamento & purificaçãoRESUMO
A multilaboratory study compared the growth of 30 fastidious anaerobes, using 5 different agar media: Wilkins-Chalgren (WC), WC with either whole or laked sheep blood, and Brucella supplemented with vitamin K(1) and hemin and either laked or whole sheep blood. The media were compared for quality and quantity of growth. Experiments were conducted either entirely in an anaerobic chamber or inoculated in ambient air with anaerobic incubation. The results showed that (1) any medium plus whole or laked blood was better than unsupplemented WC, (2) whole blood and laked blood additives gave similar results, (3) supplemented Brucella with whole or laked blood was superior to WC and WC with whole or laked blood, and (4) anaerobic and aerobic inoculation with anaerobic incubation gave similar results. Brucella agar supplemented with whole or laked blood supports the growth of fastidious anaerobic species better than the WC agars do.
Assuntos
Bactérias Anaeróbias/crescimento & desenvolvimento , Meios de Cultura , Bactérias Anaeróbias/efeitos dos fármacos , Sangue , Meios de Cultura/farmacologia , Hemina/farmacologia , Humanos , Vitamina K 1/farmacologiaRESUMO
A 5-laboratory study was performed that used the National Committee for Clinical Laboratory Standards (NCCLS) reference agar dilution method with 3 media formulations to determine whether the use of different media would affect minimum inhibitory concentration (MIC) results. Wilkins-Chalgren, Brucella-based blood agar (BRU), and Wilkins-Chalgren agar plus blood (WCB) and 6 antibiotics (clindamycin, cefoxitin, ceftizoxime, piperacillin, metronidazole, and trovafloxacin) were evaluated with 58 isolates. The MIC values were compared, and a significant correlation of >0.80 was demonstrated for all media and each antibiotic/organism group. The cumulative rate of errors for all antibiotics was 0.1%. These data indicate that a change in the NCCLS reference medium for testing of anaerobic bacteria susceptibility to either BRU or WCB will not affect the MIC results for the antibiotics and organisms evaluated.
Assuntos
Bactérias Anaeróbias , Meios de Cultura , Testes de Sensibilidade Microbiana/métodos , Antibacterianos/farmacologia , Bactérias Anaeróbias/efeitos dos fármacos , Bactérias Anaeróbias/isolamento & purificação , Sangue , Hemina/farmacologia , Humanos , Vitamina K 1/farmacologiaRESUMO
The results of a multicenter US survey using the National Committee for Clinical Laboratory Standards currently recommended methodology for measuring in vitro susceptibility of 2673 isolates of Bacteroides fragilis group species were compared from 1997 to 2000. The test panel consisted of 14 antibiotics: 3 carbapenems, 3 beta-lactam-beta-lactamase inhibitors, 3 cephamycins, 2 fluoroquinolones, clindamycin, chloramphenicol, and metronidazole. Declines in the geometric mean minimum inhibitory concentrations were seen with imipenem, meropenem, ampicillin-sulbactam, and the cephamycins. Increased geometric means were observed with the fluoroquinolones and were usually accompanied by an increase in resistance rates. Bacteroides distasonis shows the highest resistance rates among beta-lactam antibiotics, whereas Bacteroides vulgatus shows the highest resistance levels among fluoroquinolones. B. fragilis shows the lowest resistance rates for all antibiotics. All strains were susceptible to chloramphenicol and metronidazole concentrations <8 microgram/mL. The data underscore the need for species identification and continued surveillance to monitor resistance patterns.
Assuntos
Antibacterianos/farmacologia , Bacteroides fragilis/efeitos dos fármacos , Coleta de Dados , Farmacorresistência Bacteriana/fisiologia , Humanos , Testes de Sensibilidade Microbiana/normasRESUMO
In vitro surveys of antimicrobial resistance among clinically important anaerobes are an important source of information that can be used for clinical decisions in the choice of empiric antimicrobial therapy. This study surveyed the susceptibilities of 556 clinical anaerobic isolates from four large medical centers using a broth microdilution method. Piperacillin-tazobactam was the only antimicrobial agent to which all the isolates were susceptible. Similarly, imipenem, meropenem, and metronidazole were highly active (resistance, <0.5%), whereas the lowest susceptibility rates were noted for penicillin G, ciprofloxacin, and clindamycin. For most antibiotics, blood isolates were less susceptible than isolates from intra-abdominal, obstetric-gynecologic, and other sources. All isolates of the Bacteroides fragilis group were susceptible to piperacillin-tazobactam and metronidazole, while resistance to imipenem and meropenem was low (<2%). For these same isolates, resistance rates (intermediate and resistant MICs) to ampicillin-sulbactam, cefoxitin, trovafloxacin, and clindamycin were 11, 8, 7, and 29%, respectively. Among the individual species of the B. fragilis group, the highest resistance rates were noted among the following organism-drug combinations: for clindamycin, Bacteroides distasonis and Bacteroides ovatus; for cefoxitin, Bacteroides thetaiotaomicron, B. distasonis, and Bacteroides uniformis; for ampicillin-sulbactam, B. distasonis, B. ovatus, and B. uniformis; and for trovafloxacin, Bacteroides vulgatus. For the carbapenens, imipenem resistance was noted among B. fragilis and meropenem resistance was seen among B. fragilis, B. vulgatus, and B. uniformis. With few exceptions all antimicrobial agents were highly active against isolates of Prevotella, Fusobacterium, Porphyromonas, and Peptostreptococcus. These data further establish and confirm that clinically important anaerobes can vary widely in their antimicrobial susceptibilities. Fortunately most antimicrobial agents were active against the test isolates. However, concern is warranted for what appears to be a significant increases in resistance to ampicillin-sulbactam and clindamycin.
Assuntos
Bacteroides fragilis/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Fusobacterium/efeitos dos fármacos , Peptostreptococcus/efeitos dos fármacos , Porphyromonas/efeitos dos fármacos , Prevotella/efeitos dos fármacos , Infecções Bacterianas/microbiologia , Bacteroides fragilis/isolamento & purificação , Fusobacterium/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Peptostreptococcus/isolamento & purificação , Porphyromonas/isolamento & purificação , Prevotella/isolamento & purificação , Especificidade da EspécieRESUMO
BACKGROUND: A widely observed increased risk of hepatitis C virus (HCV) infection in chronic hemodialysis patients has been previously attributed to violations of "Universal Precautions" for the control of blood-borne pathogens, as well as in part, to other risk factors, such as a history of blood transfusion or injection drug use. However, specific factors responsible for transmission have not been identified and the possibility that flaws in dialysis procedures, including sterilization, could increase the risk of transmission, has not been excluded. METHODS: We investigated reuse procedures for hemodialysis equipment and tested dialyzer blood port caps for detection of hepatitis C virus RNA (HCV RNA) by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Following artificial contamination of the blood port caps with blood or fluids from human HCV-positive patients, and overnight soaking in 1% Renalin, HCV RNA was detected on 4 of 20 caps contaminated with blood, 1 of 10 contaminated with serum and 8 of 24 contaminated with dialyzer blood compartment residue. HCV RNA was also detected on 1 of 111 pairs of blood port caps collected post dialysis from HCV positive patients, after soaking the caps overnight in 1% Renalin. CONCLUSION: The results suggest that HCV RNA might be detectable on reused dialysis equipment post sterilization procedures, if residual blood or serum is not entirely or almost entirely removed prior to sterilization. This may warrant evaluation of sterilization procedures to ensure that procedures are adequate and that protocols are rigorously followed. Further studies of sterilization procedures by sensitive techniques such as RT-PCR may be indicated.
Assuntos
Unidades Hospitalares de Hemodiálise , Hepacivirus/isolamento & purificação , RNA Viral/análise , Diálise Renal/instrumentação , Reutilização de Equipamento , Hepatite C/transmissão , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , EsterilizaçãoRESUMO
Streptococcus pneumoniae is the predominant bacterial pathogen associated with acute otitis media (AOM), causing an estimated 7 million cases annually in the United States. Bacterial resistance should be considered when selecting an antimicrobial agent for otitis media. Significant increases in drug-resistant S pneumoniae are documented worldwide, and less than 50% of S pneumoniae strains are fully susceptible to penicillin in some regions of the United States. Although amoxicillin is recommended for uncomplicated AOM, treatment guidelines should be flexible and adaptable, taking into consideration local and regional susceptibility patterns, the age of the patient, the frequency of prior infections, and the response to prior therapy. Resistant organisms are more prevalent in children younger than 2 years of age and in those who have recurrent or persistent AOM. Overdiagnosing AOM, selecting inappropriate empiric therapy, or both, leads to overuse and misuse of antibiotics and causes increased drug resistance. This article reviews persistent and recurrent AOM and discusses the pitfalls of diagnosis and the practical limitations of current treatment recommendations.