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Showing papers on "Dalfopristin published in 2013"


Journal ArticleDOI
TL;DR: Although control of VRE is challenging, a laissez-faire policy would result in an increased number of infections and would create an irreversible situation, and dissemination of glycopeptide-resistant Staphylococcus aureus with van genes acquired from resistant enterococci cannot be ruled out.
Abstract: Twenty-five years ago, isolation of vancomycin-resistant Enterococcus faecium (VREm) was reported both in the UK and in France. Since then, VREm has spread worldwide in hospitals. Hospital outbreaks appeared to be related to the evolution since the end of 1980s of a subpopulation of E. faecium highly resistant to ampicillin and fluoroquinolones (the so-called clonal complex CC17) that later acquired resistance to vancomycin. CC17 isolates are presumably better adapted than other E. faecium isolates to the constraints of the hospital environment and most contain mobile genetic elements, phage genes, genes encoding membrane proteins, regulatory genes, a putative pathogenicity island and megaplasmids. Colonization and persistence are major features of VREm. Inherent characteristics of E. faecium including a remarkable genome plasticity, in part due to acquisition of IS elements, in particular IS16, have facilitated niche adaptation of this distinct E. faecium subpopulation that is multiply resistant to antibiotics. Quinupristin/dalfopristin and linezolid are licensed for the treatment of VREm infections, with linezolid often used as a first-line treatment. However, the emergence of plasmid-mediated resistance to linezolid by production of a Cfr methyltransferase in Enterococcus faecalis is worrying. Daptomycin has not been extensively evaluated for the treatment of VREm infections and resistant mutants have been selected under daptomycin therapy. Although control of VRE is challenging, a laissez-faire policy would result in an increased number of infections and would create an irreversible situation. Although so far unsuccessful, dissemination of glycopeptide-resistant Staphylococcus aureus with van genes acquired from resistant enterococci cannot be ruled out.

212 citations


Journal ArticleDOI
TL;DR: Findings demonstrate that S. aureus can enter the VBNC state in infectious biofilms, supporting previous findings on the role of staphylococcal bio Films in recurrent infections.
Abstract: Objectives: Staphylococcal biofilms are among the main causes of chronic implant-associated infections. We have recently suggested that their transformation into viable but non-culturable (VBNC) forms (i.e. forms capable of resuscitation) could be responsible for the recurrent symptoms. This work aims to establish whether Staphylococcus aureus biofilms can give rise to VBNC forms capable of being resuscitated in suitable environmental conditions, the role of different stressors in inducing the VBNC state and the conditions favouring resuscitation. Methods: S. aureus 10850 biofilms were exposed to different concentrations of antibiotic (vancomycin or quinupristin/dalfopristin) and/or to nutrient depletion until loss of culturability. The presence of viable cells and their number were examined by epifluorescence microscopy and flow cytometry. Gene expression was measured by real-time PCR. Resuscitation ability was tested by growth in rich medium containing antioxidant factors. Results: Viable subpopulations were detected in all non-culturable biofilms. However, viable cell numbers and gene expression remained constant for 150 days from loss of culturability in cells from antibiotic-exposed biofilms, but not in those that had only been starved. Resuscitation was obtained in rich medium supplemented with 0.3% sodium pyruvate or with 50% filtrate of a late-log culture. Conclusions: Our findings demonstrate that S. aureus can enter the VBNC state in infectious biofilms. The presence of vancomycin or quinupristin/dalfopristin can inadvertently induce a true VBNC state or its persistence in S. aureus cells embedded in biofilms, supporting previous findings on the role of staphylococcal biofilms in recurrent infections.

133 citations


Journal ArticleDOI
TL;DR: The increase in bacteraemia observed since 2007 in western and central Canada appears to coincide with the shift of MLST STs, which left all VRE isolates remained susceptible to daptomycin, linezolid, chloramphenicol and tigecycline.
Abstract: Objectives Vancomycin-resistant enterococci (VRE) can be associated with serious bacteraemia. The focus of this study was to characterize the molecular epidemiology of VRE from bacteraemia cases that were isolated from 1999 to 2009 as part of Canadian Nosocomial Infection Surveillance Program (CNISP) surveillance activities. Methods From 1999 to 2009, enterococci were collected from across Canada in accordance with the CNISP VRE surveillance protocol. MICs were determined using broth microdilution. PCR was used to identify vanA, B, C, D, E, G and L genes. Genetic relatedness was examined using multilocus sequence typing (MLST). Results A total of 128 cases of bacteraemia were reported to CNISP from 1999 to 2009. In 2007, a significant increase in bacteraemia rates was observed in western and central Canada. Eighty-one of the 128 bacteraemia isolates were received for further characterization and were identified as Enterococcus faecium. The majority of isolates were from western Canada (60.5%), followed by central (37.0%) and eastern (2.5%) Canada. Susceptibilities were as follows: daptomycin, linezolid, tigecycline and chloramphenicol, 100%; quinupristin/dalfopristin, 96.3%; high-level gentamicin, 71.6%; tetracycline, 50.6%; high-level streptomycin, 44.4%; rifampicin, 21.0%; nitrofurantoin, 11.1%; clindamycin, 8.6%; ciprofloxacin, levofloxacin and moxifloxacin, 1.2%; and ampicillin, 0.0%. vanA contributed to vancomycin resistance in 90.1% of isolates and vanB in 9.9%. A total of 17 sequence types (STs) were observed. Beginning in 2006 there was a shift in ST from ST16, ST17, ST154 and ST80 to ST18, ST412, ST203 and ST584. Conclusions The increase in bacteraemia observed since 2007 in western and central Canada appears to coincide with the shift of MLST STs. All VRE isolates remained susceptible to daptomycin, linezolid, chloramphenicol and tigecycline.

55 citations


Journal ArticleDOI
TL;DR: Data show that occurrence of linezolid resistance is still rare among enterococcal isolates referred to PHOL though detection of cfr in E. faecium is concerning as it has the potential to disseminate among other enterococci.

53 citations


Journal ArticleDOI
TL;DR: Evaluated the prevalence, diversity and antimicrobial susceptibilities of enterococci collected from tomato farms in the Mid-Atlantic United States, finding that E. faecalis from samples within a farm were more closely related than those from samples between farms.

51 citations


Journal ArticleDOI
TL;DR: High level of multidrug resistance to clinically important antibiotics was detected in E. faecalis strains, which showed resistance to six to seven antibiotics, especially those isolated from foods of animal origin, so it is necessary to re-evaluate the use of therapeutic antibiotics in stock farms at both regional and international levels due to the high number of multiple resistant bacteria.
Abstract: A collection of 55 enterococci (41 Enterococcus faecium and 14 E. faecalis strains) isolated from various traditional fermented foodstuffs of both animal and vegetable origins, and water was evaluated for resistance against 15 antibiotics. Lower incidence of resistance was observed with gentamicin, ampicillin, penicillin and teicoplanin. However, a high incidence of antibiotic resistance was detected for rifampicin (12 out of 14 of isolates), ciprofloxacin (9/14), and quinupristin/dalfopristin (8/14) in E. faecalis strains. Enterococcus faecium isolates were resistant to rifampicin (25/41), ciprofloxacin (23/41), erythromycin (18/41), levofloxacin (16/41), and nitrofurantoin (15/41). One Enterococcus faecalis and two E. faecium strains were resistant to vancomycin (MIC>16 μg/mL). Among 55 isolates, 27 (19 E. faecium and eight E. faecalis) were resistant to at least three antibiotics. High level of multidrug resistance to clinically important antibiotics was detected in E. faecalis strains (57% of E. faecalis versus 46% of E. faecium), which showed resistance to six to seven antibiotics, especially those isolated from foods of animal origin. So, it is necessary to re-evaluate the use of therapeutic antibiotics in stock farms at both regional and international levels due to the high number of multiple resistant (MR) bacteria. Fifty-six MR E. faecalis and E. faecium strains selected from this and previous studies (Valenzuela et al., 2008, 2010) were screened by polymerase chain reaction for antibiotic resistance genes, revealing the presence of tet(L), tet(M), ermB, cat, efrA, efrB, mphA, or msrA/B genes. The ABC Multidrug Efflux Pump EfrAB was detected in 96% of E. faecalis strains and also in 13% of E. faecium strains; this is the first report describing EfrAB in this enterococcal species. The efflux pump-associated msrA/B gene was detected in 66.66% of E. faecium strains, but not in E. faecalis strains.

39 citations


Journal ArticleDOI
TL;DR: A review of the currently available agents with MRSA activity and those in development is presented in this article, where Linezolid and quinupristin/dalfopristin have been demonstrated as effective although potential toxicities must be taken into consideration before their use.
Abstract: Resistant gram-positive infections, specifically methicillin-resistant Staphylococcus aureus (MRSA), carry an increased risk for morbidity and mortality. Historically, MRSA has been a cause of nosocomial infections, although recent reports have noted an increased prevalence in community-acquired MRSA infections. Vancomycin is the preferred agent to treat MRSA. However, cases of S. aureus with reduced susceptibility to vancomycin have been reported, prompting the need for alternative treatment options. In this review, we discuss the currently available agents with MRSA activity and those in development. Linezolid and quinupristin/dalfopristin have been demonstrated as effective although potential toxicities must be taken into consideration before their use. Daptomycin, tigecycline, telavancin, and ceftaroline are well tolerated but lack the clinical data to support a superior place in treatment over vancomycin. Several new agents in various stages of development have also demonstrated MRSA activity. Currently, vancomycin remains the gold-standard treatment option for MRSA infections. In situations that limit its use, consideration of patient-specific parameters, cost, and relevant clinical data demonstrating drug safety and efficacy should be employed for the selection of the appropriate alternative agent.

25 citations


Journal ArticleDOI
TL;DR: High colonization and antibiotic resistance in enterococcal isolates from nasal and perirectal area is revealed and Nasal colonization by enterococci in PICU is more alarming as VRE may cause infection and can transfer this resistance gene to other microorganisms like S. aureus.
Abstract: Enterococci normally inhabit the intestinal tract of humans and are also a potential pathogen in causing nosocomial infections. The increase in antibiotic resistance and transfer of antibiotic resistance gene to Staphylococcus aureus (S. aureus) due to co-colonization has increased its importance in research. The aim of the study was to evaluate local epidemiology of nasal and rectal colonization with Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) in patients of Paediatrics Intensive Care Unit (PICU) and correlation with clinical and socioeconomic factors. The nasal and perirectal swab samples were collected from 110 patients admitted in PICUs of three tertiary care hospitals of Rawalpindi Medical College, Pakistan. The identification of enterococci was done by biochemical tests and by PCR for ddl, vanA and vanB genes. Antibiotic susceptibility testing was performed by disc diffusion and MICs were determined for vancomycin, tetracycline, ciprofloxacin and oxacillin only. Out of 220 nasal and perirectal samples, 09 vancomycin-resistant enterococci (VRE) and 76 vancomycin-susceptible enterococci (VSE), consisting of 40 E. faecalis and 45 E. faecium were isolated. PCR successfully identified both species with ddl primers and VRE with vanA primer. With disc diffusion method, all isolates were resistant to most of the antibiotics tested except linezolid, quinupristin/dalfopristin, teicoplanin and vancomycin. VRE showed resistance to teicoplanin and vancomycin both and none was resistant to linezolid and quinupristin/dalfopristin. Generally, E. faecium isolates were more resistant than E. faecalis. MICs of vancomycin for nasal and perirectal VRE were 512 mg/L and 64 to 512 mg/L respectively. VRE were more in patients with prolonged hospitalization, from urban localities and those having pneumonia. Present study reveals high colonization and antibiotic resistance in enterococcal isolates from nasal and perirectal area. Nasal colonization by enterococci in PICU is more alarming as VRE may cause infection and can transfer this resistance gene to other microorganisms like S. aureus.

24 citations


Journal ArticleDOI
TL;DR: The prevalence of antibiotic resistance and the implicated mechanisms of resistance were evaluated in Enterococcus spp.

24 citations


Journal ArticleDOI
Yumi Seo1, Gilho Lee1
TL;DR: Fluoroquinolones have been the preferred antibiotics for treating CBP because of their low rate of drug resistance and are suitable therapeutic agents for E. faecalis strains causing CBP.
Abstract: Purpose: Enterococcus faecalis is one of the most common pathogens linked to chronic bacterial prostatitis (CBP). Owing to a limited number of previous studies addressing this topic, we aimed to determine the drug resistance patterns of E. faecalis strains isolated from CBP patients. Materials and Methods: One thousand twenty-one patients visited a single hospital owing to chronic prostatitis for 5 years. Culture specimens were obtained by use of a modified Meares-Stamey method. The minimal inhibitory concentrations of the antimicrobials were assessed by use of the Vitek II microbial identification system as suggested by the Clinical and Laboratory Standards Institute. Results: Forty-one samples from 41 patients who had significant E. faecalis loads for defining CBP were included in this study. The E. faecalis strains in our study were resistant to penicillin (9.7%), ampicillin (0%), ampicillin/sulbactam (0%), nitrofurantoin (0%), imipenem (0%), vancomycin (0%), teicoplanin (0%), quinupristin/dalfopristin (100%), ciprofloxacin (9.7%), levofloxacin (4.8%), norfloxacin (26.8%), erythromycin (95%), gentamicin (46.3%), tetracycline (97.5%), and trimethoprim/sulfamethoxazole (31.5%), respectively. Conclusions: Fluoroquinolones have been the preferred antibiotics for treating CBP. Because of their low rate of drug resistance, fluoroquinolones are suitable therapeutic agents for E. faecalis strains causing CBP in Korea. Even though tetracycline, erythromycin, and trimethoprim/sulfamethoxazole have been prescribed as an empirical antimicrobial therapy for chronic prostatitis, we cannot recommend these drugs for treatment of E. faecalis isolates because of the high rates of drug resistance.

19 citations


Journal ArticleDOI
TL;DR: Q/D-intermediate E. faecium is revealed, which is composed of heterogeneous strains in Japan, and more genetic diversity in the erm(B) RRs than those reported previously, and several resistance gene/virulence factor profiles are revealed.
Abstract: Cross-resistance to macrolide, lincosamide, and streptogramin B (MLSB) antibiotics is mainly mediated by the erm (erythromycin ribosome methylation) genes that encode 23S rRNA methylases in enterococi, and various mechanisms are involved in the streptogramin B resistance. Prevalence of MLSB resistance and its genetic mechanisms were analyzed for a total of 159 strains of Enterococcus faecium isolated from clinical specimens in a university hospital in Japan from 1997 to 2006. Resistance to erythromycin (EM) and clindamycin was detected in 88.1% and 89.9% of all the strains examined, respectively, and expression of resistance was totally constitutive. Although none of the strain was resistant to quinupristin/dalfopristin (Q/D), 28 strains (17.6%) showed intermediate resistance to Q/D (MIC: 2 μg/ml). The erm(B) gene was detected in 139 strains (87.4%), and msrC was found in all the strains examined, whereas no other known MLSB resistance genes were identified. The erm(B) regulator region (RR) containing a c...

Journal ArticleDOI
TL;DR: Genotypic and technological properties, antibiotic susceptibility and antimicrobial activity of 35 Leuconostoc strains, isolated from different Italian raw milk cheeses, were investigated and the results showed a high degree of heterogeneity among isolates.
Abstract: Genotypic and technological properties, antibiotic susceptibility and antimicrobial activity of 35 Leuconostoc strains, isolated from different Italian raw milk cheeses, were investigated. RAPD-PCR was used to study genetic variability and to distinguish closely related strains. The results showed a high degree of heterogeneity among isolates. All the strains had weak acidifying activity and showed low proteolytic and lipolytic activities. Reduction activity, was generally low. All the Leuconostoc were susceptible to ampicillin, mupirocin, erythromycin, quinupristin/dalfopristin and tetracycline. Many strains were classified as resistant to oxacillin, ciprofloxacin and nitrofurantonin, while all isolates were found resistant to vancomycin. PCR-based detection did not identify any of the common genetic determinants for vancomycin (vanA, vanB, vanC1, vanC2, vanC3, vanD, vanE, vanG) or erythromycin (ermB and ermC). Tetracycline resistance genes were detected in 25 tetracycline susceptible strains, the most frequent one being tetM. One strain, belonging to Ln. pseudomesenteroides species, was positive for the presence of the int gene of the Tn916/Tn1545 trasposon family. This is the first time the conjugative transposon Tn916 has been detected inside the Leuconostoc species. All strains showed antimicrobial activity against Enterococcus faecalis and Ent. faecium. The presence of genes encoding amino-acid decarboxylases (hdc and tdc) was not detected. Some strains are interesting in view of their use in cheese production as starter and non starter cultures.

Journal ArticleDOI
TL;DR: Daptomycin and quinupristin/dalfopristin were found to be effective against MRSA and MRCNS strains and were concluded to be a good choice in the treatment of methicillin-resistant staphylococci.
Abstract: Background: The treatment of methicillin-resistant staphylococcal infections has been a growing problem both in and out of hospitals for the past 30 years. Therefore, there is a need for other antibiotics as an alternative to glycopeptides in the treatment of methicillin-resistant staphylococcal infections. This study investigated the in vitro susceptibility of 49 methicillin-resistant Staphylococcus aureus (MRSA) and 59 methicillin-resistant coagulase negative staphylococci (MRCNS) clinical isolates to daptomiycin, telithromycin, tigecyclin, quinupristin/dalfopristin, and linezolid. Methodology: The identification of the strains was made by conventional methods. Antibiotic susceptibility tests were performed according to CLSI. Methicillin resistance was determined by cefoxitin disk. Susceptibilities of the strains to daptomycin, quinupristin/dalfopristin, tigecycline, and vancomycin were performed using the E-test according to the recommendations of CLSI 2011 and the manufacturer. Results: Two strains of MRCNS were resistant, and one was teicoplanin intermediate. It was found that one (2%) strain of MRSA and two (3%) strains of MRCNS were resistant to tigecyclin. Telithromycin resistance was detected in 33% of MRSA strains and 37% of MRCNS strains. Inducible clindamycin resistance was found in nine (18.4%) strains of MRSA and eighteen (30.5%) strains of MRCNS. All strains were susceptible to daptomiycin, quinupristin/dalfopristin, and linezolid. Conclusions:Although it has recently been used, telithromycin has a high percentage of resistance; its use for methicillin-resistant staphylococcal strains, therefore, should be limited. Daptomycin and quinupristin/dalfopristin were found to be effective against MRSA and MRCNS strains and were concluded to be a good choice in the treatment of methicillin-resistant staphylococci.

Journal Article
TL;DR: In 2010, 15 institutions around Australia conducted a period prevalence study of key resistances in isolates of Enterococcus species associated with a range of clinical disease amongst in- and outpatients to test for susceptibility to commonly used antimicrobials using standardised methods.
Abstract: In 2010, 15 institutions around Australia conducted a period prevalence study of key resistances in isolates of Enterococcus species associated with a range of clinical disease amongst in- and outpatients. Each institution collected up to 100 consecutive isolates and tested these for susceptibility to commonly used antimicrobials using standardised methods. Vancomycin-resistant Enterococcus faecium and Enterococcus faecalis were characterised by pulsed-field gel electrophoresis. Multilocus sequence typing was performed on representative pulsotypes of E. faecium. Susceptibility results were compared with similar surveys conducted in 1995, 1999, 2003, 2005, 2007 and 2009. In the 2010 survey, E. faecalis (1,201 isolates) and E. faecium (170 isolates) made up 98.9% of the 1,386 isolates tested. Ampicillin resistance was very common (85.3%) in E. faecium and absent in E. faecalis. Non-susceptibility to vancomycin was 36.5% in E. faecium (similar to the 35.2% in 2009 but up from 15.4% in the 2007 survey) and 0.5% in E. faecalis. There were significant differences in the proportion of vancomycin-resistant E. faecium between the states ranging from 0% in Western Australia to 54.4% in South Australia. The vanB gene was detected in 62 E. faecium and 3 E. faecalis isolates. The vanA gene was detected in 1 E. faecium isolate. All vancomycin-resistant E. faecium belonged to clonal complex 17. The most common sequence type (ST) was ST203, which was found in all regions that had reports of vancomycin resistant enterococci. ST341 was detected only in New South Wales/Australian Capital Territory and ST414 only in South Australia and Victoria. High-level resistance to gentamicin was 34.1% in E. faecalis and 66.1% in E. faecium. A subset of isolates was tested against high-level streptomycin, linezolid and quinupristin/dalfopristin. High-level streptomycin resistance was found in 8.2% of E. faecalis isolates and 43.8% of E. faecium isolates. Linezolid non-susceptibility was more common in E. faecalis (5.8%) than E. faecium (0.9%). Overall 9.4% of E. faecium were resistant to quinupristin/dalfopristin (E. faecalis is intrinsically resistant).

Journal ArticleDOI
TL;DR: Four Enterococcal UTI isolates were susceptible to Ampicillin and Aminoglycosides (high level synergy) suggesting use of combination therapy of Ampiculin and Amin Glycosides for treatment, and four Enterococci causing nosocomial urinary tract infection were sensitive to those antimicrobials.
Abstract: Enterococcal UTI is a well-known source of fatal bacteraemia & endocarditis. OBJECTIVE: Identification of different species of Enterococci causing nosocomial urinary tract infection in a tertiary care hospital along with antibiotic susceptibility pattern. METHODS: Admitted patients developing symptoms of UTI atleast after 48 hours of admission were included in this study over a period from January-June 2013.Urine samples collected in appropriate sterile manner were screened for pus cells and bacteria followed by speciation according to Facklam-Collins scheme. Enterococcal isolates were preserved in CTA until tested by VITEK2 (bioMerieux) with AES to confirm the speciation. Antibiogram was performed by disk diffusion method (modified Kirby -Bauer technique) on Muller-Hinton agar and blood agar media. MIC of the tested antibiotics was detected by VITEK 2 with AES which provides accurate "fingerprint" recognition of bacterial resistance. RESULTS: Out of total 187 urine samples, 34 were culture positive (18%) of which Enterococci were isolated in 9 cases (26.4%); E nterococ cus f aec alis & Enteroc occ us f aec ium four each along with one E nteroc occ us gallinarum strain. Isolated E nterococc us gallinarum and all isolated E nterococc us f aec alis were sensitive to Penicillin group of drugs, although all isolated Enterococcus faecium were resistant to them. None of the Enterococcal isolates produced β- lactamase. In isolated Enterococcus gallinarum and one Enterococcus faecalis isolate, MIC value of Ampicillin was double that of Benzyl-penicillin. Isolated Enterococcus gallinarum was the only Vancomycin resistant Enterococcus strain. According to VITEK2 AEC, it was of vanA type with MIC ≥32μg/ml. All four Enterococcus faecalis isolates were resistant to Quinupristin & Dalfopristin whereas isolated Enterococcus faecium were sensitive to those antimicrobials. All of the isolates were sensitive to Nitrofurantoin except one Enterococcus faecium isolate (MIC value 64μg/ml) and Enterococcus gallinarum isolate (MIC value 64μg/ml), both of which were intermediately susceptible to the drug. CONCLUSION: Four E nterococ cal isolates were susceptible to Ampicillin and Aminoglycosides (high level synergy) suggesting use of combination therapy of Ampicillin and Aminoglycosides for treatment. Vancomycin and Linezolid are the only available drugs for treatment of isolates resistant to both or any one of the drugs Ampicillin and Aminoglycosides (high level synergy). To treat VRE, Linezolid may be prescribed.

Journal Article
TL;DR: The multi-drug resistant MRSA isolated from pig- and food-associated matrixin China is very serious and the antimicrobial susceptibility of MRSA was evaluated.
Abstract: OBJECTIVE To study the mecA gene distribution in 877 strains of Staphylococcus aureus isolated from the environment of pig farm and slaughter house, pig carcass and its iliac lymph nodes, and ready-to-eat foods in China as to screen the methicillin-resistant Staphylococcus aureus (MRSA), and to evaluate the antimicrobial susceptibility of MRSA. METHODS A total of 877 strains of S. aureus that had been phenotypically identified by Gram staining, catalase test, ability to coagulate rabbit plasma, API STAPH as well as analysis of nuc gene, encoding for a S. aureus specific thermonu-clease were screened for MRSA by characterizing the mecA gene. The antimicrobial susceptibility of MRSA was tested in accordance with the broth microdilution method recommended by the Clinical and Laboratory Standards Institute. RESULTS Of 877 S. aureus strains tested, 71 (8.1%, 71/887) were mecA positive and identified as MRSA, among which, 48 isolates were pig-associated and 23 isolates were ready-to-eat food-associated. The frequency of pig-associated MRSA was significantly higher than that of food-associated one (chi2 = 53.040, P < 0.01). All MRSA were susceptible to linezolid, vancomycin, tigecycline, and nitrofurantoin but resistant to cefoxitin, oxacillin and benzylpenicillin. Meanwhile, 98.6% (70 strains), 95.8% (68 strains), 88.7% (63 strains), 80.3% (57 strains), 80.3% (57 strains) and 32.4% (23 strains) MRSA exhibited the resistance to clindamycin, erythromycin, tetracycline, ciprofloxacin, trimethoprim/sulfamethoxazole, and gentamicin, respectively. Besides, one strain was resistant to each of antibiotics including levofloxacin, moxifloxacin, rifampicin, and quinupristin/dalfopristin. It was worth noting that the frequency of resistance to ciprofloxacin, tetracycline, and trimethoprim/sulfamethoxazole of pig-associated MRSA was significantly higher than that of food-associated MRSA (CIP: chi2 = 29.110, P < 0.01, TET: chi2 = 18.816, P < 0.01, TMP/ SMZ: chi2 = 36.394, P < 0.01). It should be pointed out that 70 (98.6%) strains of MRSA were multi-drug resistant and eight spectrums of antimicrobial susceptibility were observed. CONCLUSION The multi-drug resistant MRSA isolated from pig- and food-associated matrixin China is very serious.

Journal ArticleDOI
TL;DR: In a 49-year-old renal and pancreatic female transplant recipient, who presented a drug interaction between tacrolimus, warfarin and pristinamycin, the patient presented nausea, vomiting, abdominal pain and violent headaches that required hospitalization.
Abstract: We report the case of a 49-year-old renal and pancreatic female transplant recipient, who presented a drug interaction between tacrolimus, warfarin and pristinamycin. Three days after oral pristinamycin 1000 mg bid administrations, the patient presented nausea, vomiting, abdominal pain and violent headaches that required hospitalization. Tacrolimus trough level was 5 times higher (34.9 μg/l) than the target required (5-8 μg/l) and the INR was at 5.8 (therapeutic index between 2 and 3) despite a stable kidney function (serum creatinine 130 μmol/L) and no other organic disorders. Five days following discontinuation, drug monitoring revealed adequate tacrolimus plasma trough concentrations (8.9 μg/l) and the INR subsequently decreased. Pristinamycin is an antibiotic effective against the majority of Gram positive bacteria. This drug is an inhibitor of the multidrug transporter P-glycoprotein (P-gp) that could lead to the accumulation of tacrolimus. Moreover, pristinamycin IIA is the active metabolite of quinupristin/dalfopristin which, is known to be an inhibitor of cytochrome P450 3A4 (CYP 3A4). Our case supposes that pristinamycin is also an inhibitor of CYP 3A4 that can lead to an increase of tacrolimus levels. This case report brings to light potential drug interactions of pristinamycin with narrow therapeutic index drugs such as tacrolimus and warfarin.

01 Jan 2013
TL;DR: Interestingly, relations between eap presence and change in the antimicrobial sensitivity pattern before and after irradiation were highly significant for amoxicillin/clavulanic acid and significant for quinupristin/dalfopristin indicating the association between missing the encoding gene after irradiated and shifting to antibiotic susceptibility.
Abstract: Extracellular adherence protein (Eap) constitutes an important virulence factor enhancing binding and internalization of Staphylococcus aureus into eukaryotic cells. In the present study 63 S. aureus isolates from cancer patients were examined for the existence of the Eap-encoding gene (eap) before and after in vitro X-irradiation using PCR amplification to determine whether this gene could be used as a molecular diagnostic target for sensitive detection and identification of S. aureus infections in X-ray treated cancer patients. Also, to investigate the relations to their antimicrobial sensitivities. The prevalence of the eap gene was (100%) before irradiation however, only (55.56%) were shown to harbor this gene after irradiation (P<0.001). The incidence of linezolid and vancomycin susceptibility was high (100%), while, it was (97.14%) & (94.29%) for Eap-bearing isolates after irradiation, respectively. Interestingly, relations between eap presence and change in the antimicrobial sensitivity pattern before and after irradiation were highly significant for amoxicillin/clavulanic acid (P = 0.000), chloramphenicol (P = 0.006), levofloxacin (P= 0.003), meropenem (P = 0.000), minocycline (P = 0.000), oxacillin(P = 0.000) and penicillin (P=0.002) and significant for quinupristin/dalfopristin (P= 0.038) indicating the association between missing the encoding gene after irradiation and shifting to antibiotic susceptibility.

Patent
17 Oct 2013
TL;DR: In this paper, a separation and purification method for dalfopristin and an intermediate thereof was proposed, which is economical and highly efficient, and achieves ideal selectivity and purity effects on isomer impurities.
Abstract: The present invention relates to a separation and purification method for an organic compound in the chemical field. Specifically, the present invention relates to a separation and purification method for dalfopristin and an intermediate thereof. The method of the present invention is economical and highly-efficient, and achieves ideal selectivity and purification effects on isomer impurities in the crude product of dalfopristin or dalfopristin intermediate. The dalfopristin or dalfopristin intermediate product having purity higher than 99% can be obtained by performing separation and purification for once, and the yield is high.