Objective:To evaluate the prevalence of multidrug resistant Staphylococcus aureus(S.aureus) in dairy products.Methods:Isolation and identification of S.aureus were performed in 3 dairybased food products.The isolates ...Objective:To evaluate the prevalence of multidrug resistant Staphylococcus aureus(S.aureus) in dairy products.Methods:Isolation and identification of S.aureus were performed in 3 dairybased food products.The isolates were tested for their susceptibility to 5 different common antimicrobial drugs.Results:Of 50 samples examined,5(10%) were contaminated with 5. aureus.Subsequently,the 5 isolates were subjected to antimicrobial resistance pattern using five antibiotic discs(methicillin,vancomycin,kanamycin,chloramphenicol and tetracycline).Sample 29 showed resistance to methicillin and vancomycin.Sample 18 showed intermediate response to tetracycline.The other samples were susceptible to all the antibiotics tested.Conclusions:The results provide preliminary data on sources of food contamination which may act as vehicles for the transmission of antimicrobial-resistant Staphylococcus.Therefore,it enables us to develop preventive strategies to avoid the emergence of new strains of resistant S.aureus.展开更多
Objective:To investigate the antibacterial aclivily of marine actinobacteria against multidrug resistance Staphylococcus aureus(MDRSA).Methods:Fifty one actinobacterial strains were isolated from salt pans soil,costal...Objective:To investigate the antibacterial aclivily of marine actinobacteria against multidrug resistance Staphylococcus aureus(MDRSA).Methods:Fifty one actinobacterial strains were isolated from salt pans soil,costal area in Kothapattanam,Ongole,Andhra Pradesh.Primary screening was done using cross-streak method against MDRSA.The bioaclive compounds are extracted from efficient actinobacteria using solvent extraction.The antimicrobial activity of crude and solvent extracts was perfomied using Kirby-Bauer method.MIC for ethyl acetate extract was determined by modified agar well diffusion method.The potent actinobacteria are identified using Nonomura key,Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology.Results:Among the fifty one isolates screened for antibacterial activity,SRB25were found efficient against MDRSA.The ethyl acetate extracts showed high inhibition against test organism.MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000μg/mL.The isolaled actinobacteria are identified as Streptomyces sp with the help of Nonomura key.Conclusions:The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.展开更多
Objective:To investigate the infection of hospital-and community-acquired"erythromycininduced clindamycin resistant"strains or D-test positives of clinical isolates of Staphylococcus aureus(S.aureus)(with an...Objective:To investigate the infection of hospital-and community-acquired"erythromycininduced clindamycin resistant"strains or D-test positives of clinical isolates of Staphylococcus aureus(S.aureus)(with and without methicillin resistance)in a hospital.Methods:Strains of S.aureus isolated from clinical specimens were subjected to D-test and antibiotic profiling.Results:Of the total 278 isolates,140(50.35%)were D-test positives and the rest were D-test negatives.Further,of 140(100%)pesitives,87(62.14%)and 53(37.85%)strains were from males and females,respectively.Of 140(100%)pesitives,117(83.57%)were methicillin resistant S.aureus and23(16.42%)were methicillin sensitive S.aureus;of 140 strains,103(73.57%)strains front persons with and 37(26.42%)were without related infections;of 140 strains,91(65%)and 49(35%)were from hospital-and community-acquired samples,respectively.In 140 strains,118(84.28%)with comorbidities and 22(15.71%)without comorbidities cases were recorded;similarly,persons with prior antibiotic uses contributed 108(77.14%)and without 32(22.85%)positive strains.These binary data of surveillance were analyzed by a univariate analysis.It was evident that the prior antibiotic uses and comorbidities due to other ailments were the determinative factors in D-test positivity,corroborated by low P values,P=0.001 1 and 0.0024,respectively.All isolates(278)were resistant to17 antibiotics of nine groups,in varying degrees;the minimum of 28%resistance for vancomycin and the maximum of 97%resistance for gentamicin were recorded.Further,of 278 strains,only42(15.1%)strains were resistant constitutively to both antibiotics,erythromycin resistant and clindamycin resistant,while 45(16.2%)strains were constitutively sensitive to both antibiotics(erythromycin sensitive,and clindamycin sensitive).Further,of the rest 191(68.7%)strains were with erythromycin resistant and clindamycin resistant,of which only 140(50.35%)strains were D-test positives,while the rest 51(18.34%)strains were D-test negatives.Conclusions:In view of high prevalence of D-test positive S.aureus strains,and equally high prevalence of multidrug resistant strains both in community and hospital sectors,undertaking of D-test may be routinely conducted for suppurative infections.展开更多
Objective To analyze the change in drug resistance of staphylococcus aureus(SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics...Objective To analyze the change in drug resistance of staphylococcus aureus(SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications. Methods The SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards(NCCLS) guidelines. Results SAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillinresistant staphylococcus aureus(MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive staphylococcus aureus(MSSA)(P<0.05). In the dynamic observation of drug resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years. Conclusion Drug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.展开更多
Objective:To determine the pattern of antibiotic resistance among Staphylococcus aureus(S. aureus) isolates from clinical specimens and to identify community-acquired methicillin-resistant Staphylococcus aureus(CA-MRS...Objective:To determine the pattern of antibiotic resistance among Staphylococcus aureus(S. aureus) isolates from clinical specimens and to identify community-acquired methicillin-resistant Staphylococcus aureus(CA-MRSA) in specimens that have been collected from patients referring to one of the hospitals of Ahvaz.Methods:S.aureus isolates from a hospital in Ahvaz were screened for resistance to various antibiotics including methicillin.The susceptibility of the isolates was determined by Kirby-Bauer disc diffusion method.The MRSA was also treated with ethidium bromide to find the origin of resistance.Results:Among the bacterial isolates,all of 11 S.aureus were resistant to methicillin and cefixime,2 were resistant to ciprofloxacin,6 were resistant to tetracycline and the reminder were sensitive or intermediate to other antibiotics.The treated isolates were reminded resistant to methicillin and this suggested that the plasmid was not the origin of resistance in these isolates.Conclusions:These results showed that infection due to MRSA is widespread in Ahvaz and with respect to the spread of vancomycin resistance among MRSA and appearance of overwhelming infections.It is necessary to identify continuously the profile of antibiotic resistance among S.aureus isolates in other regions and finding appropriate antibiotic for infection control and eradication.展开更多
Purpose: To capture the sensitivity and resistance trends of ophthalmic Methicillin-resistant Staphylococcus aureus (MRSA) in a heterogenous demographic. Methods: Between 1/1/2004-12/31/2011, ophthalmic MRSA infection...Purpose: To capture the sensitivity and resistance trends of ophthalmic Methicillin-resistant Staphylococcus aureus (MRSA) in a heterogenous demographic. Methods: Between 1/1/2004-12/31/2011, ophthalmic MRSA infections were searched in the electronic medical record system ofCommunityRegionalMedicalCenterinFresno,California. We reviewed whether the infection was community-acquired or hospital-acquired, culture site, and sensitivity/resistance profiles. Results: The ophthalmic MRSA isolates tested for vancomycin, sulfamethoxazole-trimethoprim, and gentamycin were 100% sensitive to these to these antibiotics. Tetracycline and rifampin had the next highest sensitivity to resistance ratio, followed by clindamycin. More cases were community-acquired than hospital acquired. Almost half of the hospital-acquired cases were in newborns. Most hospital acquired infections were post-ophthalmic surgery. Conclusion: There is an increasing trend of community- acquired ophthalmic MRSA infection with eyelid involvement being the most common manifestation. Hospital-acquired cases are common in newborns and post-ophthalmic surgery. Have a high index of suspicion for MRSA infection with suspected “insect bites”. Vancomycin, sulfamethoxazole-trimethoprim, gentamycin, tetracycline, and rifampin are good choices to treat ophthalmic MRSA infection. There may be emerging resistance to clindamycin, at least in theCentral Californiaregion. If MRSA infection is suspected, erythromycin and fluoroquinolones should be avoided.展开更多
目的:通过Meta分析研究骨髓炎患者中耐甲氧西林金黄色葡萄球菌(MRSA)的感染率。方法:检索PubMed、Web of Science、中国知网、维普、万方和中国生物医学文献数据库(CBM)关于骨髓炎患者MRSA感染率的研究,检索时限为建库至2023年8月。由2...目的:通过Meta分析研究骨髓炎患者中耐甲氧西林金黄色葡萄球菌(MRSA)的感染率。方法:检索PubMed、Web of Science、中国知网、维普、万方和中国生物医学文献数据库(CBM)关于骨髓炎患者MRSA感染率的研究,检索时限为建库至2023年8月。由2位研究人员按照纳入与排除标准对所获文献独立进行筛选、提取,采用纽卡斯尔-渥太华量表评分(NOS)进行文献质量评价。以感染率为结局指标合并数据,采用R(4.3.1)进行Meta分析,并根据骨髓炎类型、患者年龄、研究地区进行亚组分析。结果:共纳入26篇文献,共包含20860名骨髓炎患者。Meta分析结果显示,骨髓炎患者MRSA感染率为0.240(95%CI:0.183~0.297)。亚组分析结果显示,椎体骨髓炎(VO)患者、18~60岁、北美地区骨髓炎患者的MRSA感染率更高。结论:骨髓炎患者中MRSA的感染率较高,需采取有效的预防和控制措施减少MRSA的传播。展开更多
Background: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most problematic human pathogens. Antibiotic treatment of MRSA often associated with resistance to multiple classes of antibiotics is extrem...Background: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most problematic human pathogens. Antibiotic treatment of MRSA often associated with resistance to multiple classes of antibiotics is extremely challenging and urgently demands action to treat MRSA. Glutathione (GSH) is a biogenic thiol-compound that maintains an optimal intracellular redox-potential required for various normal cellular processes. Antibacterial activity of exogenous GSH has been reported in some bacterial pathogens but is largely unknown in MRSA. Aim: This study aimed to understand antibacterial activity of GSH, its role in antibiotic susceptibility, and a potential antibacterial mechanism in clinical isolates of S. aureus. Materials and Methods: Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), checkerboard, time-killing, and bacterial killing assays were performed for 14 clinical isolates of S. aureus including 10 MRSA and two type strains (ATCC 700699 and 35556). Results: MIC and MBC levels for the clinical and type strains were 15 - 20 mM and 25 - 40 mM of GSH, respectively. Subinhibitory concentrations of GSH synergistically enhanced susceptibility of all tested-antibiotics, resulting in sensitizing all-tested S. aureus. Bacterial-killing produced by GSH-mediated acidity was significantly higher than that by hydrochloric acid-mediated acidity. Conclusion: Overall results concluded that GSH exhibited antibacterial activity on S. aureus regardless of antibiotic susceptibility and synergistically enhanced antibiotic susceptibility. Additionally, GSH-mediated acidity was one of the antibacterial mechanisms. These findings suggest that GSH may be a potential antimicrobial agent or adjuvant for the conventional anti-MRSA regimens.展开更多
There are various bacteria living in this world. The most common one is Staphylococcus aureus. Almost everyone has heard of it. It is easy to find their habitats, such as hospitals, homes, parks, schools etc. Some of ...There are various bacteria living in this world. The most common one is Staphylococcus aureus. Almost everyone has heard of it. It is easy to find their habitats, such as hospitals, homes, parks, schools etc. Some of them are difficult to be eliminated because of drug-resistant mutations. Hence, lots of researchers devoted their efforts to eliminate them. This review illustrates the characteristics of the Staphylococcus aureus and the main threat of their drug-resistant strains, especially methicillin-resistant S. aureus. What’s more, the article also highlights the plight in the drug development.展开更多
Methicillin-resistant Staphylococcus aureus(MRSA)strains are the essential cause of infections in communities and hospitals.The present study was conducted to determine the molecular typing of MRSA,isolated from hospi...Methicillin-resistant Staphylococcus aureus(MRSA)strains are the essential cause of infections in communities and hospitals.The present study was conducted to determine the molecular typing of MRSA,isolated from hospitalized patients,using the double-locus sequence typing(DLST).In total,280 S.aureus isolated from clinical specimens by phenotypic(catalase,coagulase,DNase,oxacillin,vancomycin screening agar and antibiotic disk diffusion),and molecular methods(PCR for determining the mecA,vanA and nuc genes).The DLST and sequencing was performed for MRSA containing mecA.Out of 280 specimens,confirmed as Staphylococcus aureus(S.aureus),123(43.9%)strains were MRSA.The highest resistance toward the erythromycin(15μg),followed by ciprofloxacin(5μg),clindamycin(2μg),tetracycline(30μg),gentamicin(10μg)and rifampicin(5μg),was 98.3%,97.5%,94.3%,90.2%,83.7%and 41.4%,respectively.Also,the least resistance(0%)was observed in each of teicoplanin(30μg),linzolide(30μg),and vancomycin(30μg).All(100%)of MRSA strains had the mecA,and none of them have had the vanA.The results of DLST showed that the most common sequence types were BPH 2003 and 0217.The DLST type 18-32 was a significant cluster of MRSA.By sequencing MRSA and comparing the dominant types via the DLST,it is possible to establish the etiology of the disease in a much shorter time,and prevent the complications of the disease.Therefore,the combination of partial sequences of clfB and spa can serve as useful genetic markers for MRSA typing.It concluded that the MRSA in our region was relatively high,but no vancomycin resistance was found.The majority of the MRSA DLST type was 18–32.展开更多
Objective:This study was conducted to update the prevalence of methicillin-resistant Staphylococcus aureus(MRSA) isolates among human clinical S.aureus isolates recovered from Northern Palestine,to evaluate the possib...Objective:This study was conducted to update the prevalence of methicillin-resistant Staphylococcus aureus(MRSA) isolates among human clinical S.aureus isolates recovered from Northern Palestine,to evaluate the possible presence of vancomycin-Resistant S.aureus(VRSA) and vancomycin- intermediate resistant S.aureus strains(VISA) and to determine the antimicrobial susceptibilities of these clinical isolates.Methods:The in vitro activities of 11 antibiotics against 204 non-duplicate S.aureus isolates from clinical samples in North of Palestine were determined by the diskdiffusion method.These samples were isolated between June 2006 and December 2007.The minimum inhibitory concentration (MIC) of vancomycin for 115 methicillin resistant Staphylococcus aureus(MRSA) strains was carried out using the agar dilution method.Results:One hundred and fifteen(56.4%) of these isolates were MRSA and according to their antibiotic profile these are multidrug resistant(resistant to three or more non-p-lactam antibiotics). Ninety nine(43.6%) isolates were methicillin sensitive S.aureus(MSSA),forty four of MSSA isolates(44.4%) were multidrug resistant,while forty five(45.6%) were non multidrug resistant.Our results showed that the most common resistance(95.6%) was to penicillin.Two strains of MRSA have shown to be vancomycin- intermediate resistant,had MIC of 4μg/rnL and 8μg/mL and these vancomycin- intermediate resistant S.aureus strains(VISA) are resistant to all antibiotics tested.Conclusion:According to our information this is the first study report about VISA in Palestine.展开更多
The purpose of this subject was to investigate molecular epidemiology of oxacillin-resistant Staphylococcus aureus (MRSA) isolated from hospitalized patients, and to survey the in vitro activity of teicoplanin, vancom...The purpose of this subject was to investigate molecular epidemiology of oxacillin-resistant Staphylococcus aureus (MRSA) isolated from hospitalized patients, and to survey the in vitro activity of teicoplanin, vancomycin and other 9 antibiotics against Staphylococcus species . MRSA were detected by oxacillin-NaCl-containing screen agar. The homology of nosocomial MRSA from ICU and RCU was determined by pulse-field gel electrophoresis. Agar diffusion, E test and agar dilution were used to compare the in vitro activity of teicoplanin and vancomycin against Staphylococcus spp from 2001 to 2003 at Peking Union Medical College Hospital. WHONET-5.3 software was used to analyze the antimicrobial susceptibility data. From 2001 to 2003, the prevalences of MRSA were 56.5%, 65.3%, 64.7%, respectively. PFGE found most of MRSA from ICU and RCU were closely related. All of S.aureus and S.epidimidis isolates were susceptible to teicoplanin and vancomycin from 2001 to 2003. However, 1 isolate of S.haemolyticus was resistant and 9 isolates intermediate to teicoplanin. The minimal inhibitory concentration of teicoplanin did not correlate well with zone diameter, when inoculum increased by 100 folds, the zone diameters of teicoplanin decreased more greatly than those of vancomycin. In 2002, severe outbreaks caused by MRSA strains had been found in ICU and RCU wards. Teicoplanin and vancomycin had good activity against clinical isolates of Staphylococci spp . Teicoplanin was less active than vancomycin against S.haemolyticus . Most of S.haemolyticus isolates were intermediate to teicoplanin. Antimicrobial susceptibility testing of teicoplanin was influenced by the diffusion speed in the agar and inoculum size.展开更多
Introduction: Staphylococcus aureus is one of the most important agents involved in community and hospital-acquired infections. Due to the multi-drug resistance of strains to antibiotics, treatment to eradicate it is ...Introduction: Staphylococcus aureus is one of the most important agents involved in community and hospital-acquired infections. Due to the multi-drug resistance of strains to antibiotics, treatment to eradicate it is becoming more difficult and poses a global public health problem. Methodology: This was a cross-sectional study conducted from March to August 2020 in hospitals in the city of Douala, including all S. aureus isolates from diagnostic samples. Strain identification and antibiotic susceptibility testing were performed using the Vitek2 Compact<sup>TM</sup> (BioMerieux). Results: During the study period, 136 non-repetitive S. aureus strains were identified with a high frequency of methicillin-resistant S. aureus of 78.7%. The majority of the strains originated from the Douala General Hospital (66.9%) and was most frequently isolated from blood culture samples (55.1%). The study of biochemical characteristics showed that most of the strains identified had between 87% and 99% homology with the reference strain. The most active antibiotics were Quinupristin/Dalfopristin (94.2%), Linezolid (87.8%) and Vancomycin (84.2%). Methicillin resistance was associated with decreased susceptibility of S. aureus to other antibiotics such as Gentamycin (44.9%), Erythromycin (38.2%), Tetracycline (38.3%), Trimethoprim (21.4%), Ciprofloxacin (19.1%) and Levofloxacin (24.0%). Inducible MLSb and constitutive resistance phenotypes were identified with 26.7% and 22.8% respectively. Conclusion: The sensitivity of S. aureus strains differs from one antibiotic family to another, and remains good for molecules that are not available in our context. The high frequency of Methicillin-Resistant S. aureus shows the continuous progression of multi-resistant strains of S. aureus and their decreased sensitivity to usual antibiotics becomes more and more alarming.展开更多
Staphylococcus aureus infection remains an increasing problem for higher morbidity and mortality in burn patients. We sought to determine the frequency of methicillin-resistant S. aureus (MRSA) in burn wound patients ...Staphylococcus aureus infection remains an increasing problem for higher morbidity and mortality in burn patients. We sought to determine the frequency of methicillin-resistant S. aureus (MRSA) in burn wound patients and study their drug resistance genes. Samples were collected (August 2010 to October 2011) from burn unit of Dhaka Medical College Hospital (DMCH), Bangladesh. MRSA was identified by conventional culture based methods. S. aureus was confirmed in 44.44% burn wound samples and 22.5% of the isolates were oxacillin resistant. All the S. aureus isolates were resistant to commonly used drugs like amoxicillin, azactam, erythromycin, azithromycin etc. and were sensitive to imipenem. The isolates were devoid of plasmid and the gene mecA, femA and IS431 were detected in their chromosomal DNA. Computational analysis of mecA gene sequence showed homology to S. aureus “penicillin binding protein 2a” (PBP-2a). The higher association of MRSA is in burn unit of DMCH, Bangladesh is alarming and with inappropriate antibiotic use, and the situation gets even complicated to treat. Therefore, the detection system and control practices for MRSA in DMCH should be improved in the hospital settings.展开更多
The spread of antibiotic resistance, whether in the community or in the hospital, has recently become a major public health problem. Moreover, livestock seems to be a reservoir of resistant microorganisms such as porc...The spread of antibiotic resistance, whether in the community or in the hospital, has recently become a major public health problem. Moreover, livestock seems to be a reservoir of resistant microorganisms such as porcine methicillin resistant Staphylococcus aureus (P-MRSA) whose carriage and transmission was mainly demonstrated in persons with occupational exposure to pigs. Much uncertainty remains about the public health implications of P-MRSA. To address concerns that exist regarding the zoonotic risk that pig carriers pose to breeders, the prevalence of P-MRSA in pigs and pig breeders was determined among 152 pig breeders in three regions of Cameroon. Materials and Method: Participants in this study came from Adamawa, Far North and Littoral regions of Cameroon. A total of 152 pig breeders or farm workers participated in this study. After having collected some social and cultural data with the aid of a questionnaire, nasal swabs were collected from pigs (n = 275) and their breeders using the standard collection procedures and placed in cooler containing cold accumulators. For each sample, microbiological assays were done as well as antibiotic susceptibility tests. Results: MRSA was isolated from 25 out of 275 pigs sampled (9.09%) and from 32 out of 152 (21.05%) pig breeders sampled;33 breeders (21.71%) were carriers of S. aureus including 32 MRSA and one MSSA. The prevalence of MRSA nasal carriage was 21.05% ± 6.48. A significant negative association between body protection and nasal carriage of MRSA (OR = 0.29, 95% CI [0.093;0.93];p = 0.04) was observed. In each region, similar strains of MRSA were isolated both in pigs and their breeders with the same antibiotic resistant profile. Conclusion: The prevalence of MRSA though not high compared to European countries warrants further research as data on this zoonosis is scarce in our context. As such, transmission of MRSA from pigs to pig breeders or vice-versa constitutes a real danger, and this relationship may be a starting point for MRSA contamination in the community. Moreover, proper use of body protections and antibiotic medications as recommended will be a better protective measure against nasal MRSA carriage.展开更多
Epidemiological surveillance for microbes is currently based on either agar culture followed by identification, or genetic amplification. Both techniques are highly skilled-labor intensive, costly, and must be done in...Epidemiological surveillance for microbes is currently based on either agar culture followed by identification, or genetic amplification. Both techniques are highly skilled-labor intensive, costly, and must be done in central laboratories. The Defined Substrate Utilization®(DSU®) format provides an epidemiological series of specific screening formulations that obviate these limitations. All reagents are present in optimized stable powder form in a test tube—add water, inoculate, and incubate. A specific color change provides a sensitive and specific detection of the target microbe. Two DSU®methods for Staphylococcus aureus (S. aureus) are presented: aureusAlert®for all S. aureus and EPI-M®for methicillin-resistant S. aureus (MRSA). Both aureusAlert®and EPI-M®had a detection level of 20 colony forming units (CFU) in 18 hours. aureusAlert®and conventional methods agreed 93.6% and EPI-M®and conventional methods agreed 94.1%. DSU®and conventional methods showed the same specificity.展开更多
文摘Objective:To evaluate the prevalence of multidrug resistant Staphylococcus aureus(S.aureus) in dairy products.Methods:Isolation and identification of S.aureus were performed in 3 dairybased food products.The isolates were tested for their susceptibility to 5 different common antimicrobial drugs.Results:Of 50 samples examined,5(10%) were contaminated with 5. aureus.Subsequently,the 5 isolates were subjected to antimicrobial resistance pattern using five antibiotic discs(methicillin,vancomycin,kanamycin,chloramphenicol and tetracycline).Sample 29 showed resistance to methicillin and vancomycin.Sample 18 showed intermediate response to tetracycline.The other samples were susceptible to all the antibiotics tested.Conclusions:The results provide preliminary data on sources of food contamination which may act as vehicles for the transmission of antimicrobial-resistant Staphylococcus.Therefore,it enables us to develop preventive strategies to avoid the emergence of new strains of resistant S.aureus.
基金financial support for the completion of this work
文摘Objective:To investigate the antibacterial aclivily of marine actinobacteria against multidrug resistance Staphylococcus aureus(MDRSA).Methods:Fifty one actinobacterial strains were isolated from salt pans soil,costal area in Kothapattanam,Ongole,Andhra Pradesh.Primary screening was done using cross-streak method against MDRSA.The bioaclive compounds are extracted from efficient actinobacteria using solvent extraction.The antimicrobial activity of crude and solvent extracts was perfomied using Kirby-Bauer method.MIC for ethyl acetate extract was determined by modified agar well diffusion method.The potent actinobacteria are identified using Nonomura key,Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology.Results:Among the fifty one isolates screened for antibacterial activity,SRB25were found efficient against MDRSA.The ethyl acetate extracts showed high inhibition against test organism.MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000μg/mL.The isolaled actinobacteria are identified as Streptomyces sp with the help of Nonomura key.Conclusions:The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.
基金supported by the research scheme from CSIR(New Delhi),No.21(0859)/11/EMR-11
文摘Objective:To investigate the infection of hospital-and community-acquired"erythromycininduced clindamycin resistant"strains or D-test positives of clinical isolates of Staphylococcus aureus(S.aureus)(with and without methicillin resistance)in a hospital.Methods:Strains of S.aureus isolated from clinical specimens were subjected to D-test and antibiotic profiling.Results:Of the total 278 isolates,140(50.35%)were D-test positives and the rest were D-test negatives.Further,of 140(100%)pesitives,87(62.14%)and 53(37.85%)strains were from males and females,respectively.Of 140(100%)pesitives,117(83.57%)were methicillin resistant S.aureus and23(16.42%)were methicillin sensitive S.aureus;of 140 strains,103(73.57%)strains front persons with and 37(26.42%)were without related infections;of 140 strains,91(65%)and 49(35%)were from hospital-and community-acquired samples,respectively.In 140 strains,118(84.28%)with comorbidities and 22(15.71%)without comorbidities cases were recorded;similarly,persons with prior antibiotic uses contributed 108(77.14%)and without 32(22.85%)positive strains.These binary data of surveillance were analyzed by a univariate analysis.It was evident that the prior antibiotic uses and comorbidities due to other ailments were the determinative factors in D-test positivity,corroborated by low P values,P=0.001 1 and 0.0024,respectively.All isolates(278)were resistant to17 antibiotics of nine groups,in varying degrees;the minimum of 28%resistance for vancomycin and the maximum of 97%resistance for gentamicin were recorded.Further,of 278 strains,only42(15.1%)strains were resistant constitutively to both antibiotics,erythromycin resistant and clindamycin resistant,while 45(16.2%)strains were constitutively sensitive to both antibiotics(erythromycin sensitive,and clindamycin sensitive).Further,of the rest 191(68.7%)strains were with erythromycin resistant and clindamycin resistant,of which only 140(50.35%)strains were D-test positives,while the rest 51(18.34%)strains were D-test negatives.Conclusions:In view of high prevalence of D-test positive S.aureus strains,and equally high prevalence of multidrug resistant strains both in community and hospital sectors,undertaking of D-test may be routinely conducted for suppurative infections.
文摘Objective To analyze the change in drug resistance of staphylococcus aureus(SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications. Methods The SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards(NCCLS) guidelines. Results SAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillinresistant staphylococcus aureus(MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive staphylococcus aureus(MSSA)(P<0.05). In the dynamic observation of drug resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years. Conclusion Drug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.
基金Shahid Chamran University for providing the research grant
文摘Objective:To determine the pattern of antibiotic resistance among Staphylococcus aureus(S. aureus) isolates from clinical specimens and to identify community-acquired methicillin-resistant Staphylococcus aureus(CA-MRSA) in specimens that have been collected from patients referring to one of the hospitals of Ahvaz.Methods:S.aureus isolates from a hospital in Ahvaz were screened for resistance to various antibiotics including methicillin.The susceptibility of the isolates was determined by Kirby-Bauer disc diffusion method.The MRSA was also treated with ethidium bromide to find the origin of resistance.Results:Among the bacterial isolates,all of 11 S.aureus were resistant to methicillin and cefixime,2 were resistant to ciprofloxacin,6 were resistant to tetracycline and the reminder were sensitive or intermediate to other antibiotics.The treated isolates were reminded resistant to methicillin and this suggested that the plasmid was not the origin of resistance in these isolates.Conclusions:These results showed that infection due to MRSA is widespread in Ahvaz and with respect to the spread of vancomycin resistance among MRSA and appearance of overwhelming infections.It is necessary to identify continuously the profile of antibiotic resistance among S.aureus isolates in other regions and finding appropriate antibiotic for infection control and eradication.
文摘Purpose: To capture the sensitivity and resistance trends of ophthalmic Methicillin-resistant Staphylococcus aureus (MRSA) in a heterogenous demographic. Methods: Between 1/1/2004-12/31/2011, ophthalmic MRSA infections were searched in the electronic medical record system ofCommunityRegionalMedicalCenterinFresno,California. We reviewed whether the infection was community-acquired or hospital-acquired, culture site, and sensitivity/resistance profiles. Results: The ophthalmic MRSA isolates tested for vancomycin, sulfamethoxazole-trimethoprim, and gentamycin were 100% sensitive to these to these antibiotics. Tetracycline and rifampin had the next highest sensitivity to resistance ratio, followed by clindamycin. More cases were community-acquired than hospital acquired. Almost half of the hospital-acquired cases were in newborns. Most hospital acquired infections were post-ophthalmic surgery. Conclusion: There is an increasing trend of community- acquired ophthalmic MRSA infection with eyelid involvement being the most common manifestation. Hospital-acquired cases are common in newborns and post-ophthalmic surgery. Have a high index of suspicion for MRSA infection with suspected “insect bites”. Vancomycin, sulfamethoxazole-trimethoprim, gentamycin, tetracycline, and rifampin are good choices to treat ophthalmic MRSA infection. There may be emerging resistance to clindamycin, at least in theCentral Californiaregion. If MRSA infection is suspected, erythromycin and fluoroquinolones should be avoided.
文摘目的:通过Meta分析研究骨髓炎患者中耐甲氧西林金黄色葡萄球菌(MRSA)的感染率。方法:检索PubMed、Web of Science、中国知网、维普、万方和中国生物医学文献数据库(CBM)关于骨髓炎患者MRSA感染率的研究,检索时限为建库至2023年8月。由2位研究人员按照纳入与排除标准对所获文献独立进行筛选、提取,采用纽卡斯尔-渥太华量表评分(NOS)进行文献质量评价。以感染率为结局指标合并数据,采用R(4.3.1)进行Meta分析,并根据骨髓炎类型、患者年龄、研究地区进行亚组分析。结果:共纳入26篇文献,共包含20860名骨髓炎患者。Meta分析结果显示,骨髓炎患者MRSA感染率为0.240(95%CI:0.183~0.297)。亚组分析结果显示,椎体骨髓炎(VO)患者、18~60岁、北美地区骨髓炎患者的MRSA感染率更高。结论:骨髓炎患者中MRSA的感染率较高,需采取有效的预防和控制措施减少MRSA的传播。
文摘Background: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most problematic human pathogens. Antibiotic treatment of MRSA often associated with resistance to multiple classes of antibiotics is extremely challenging and urgently demands action to treat MRSA. Glutathione (GSH) is a biogenic thiol-compound that maintains an optimal intracellular redox-potential required for various normal cellular processes. Antibacterial activity of exogenous GSH has been reported in some bacterial pathogens but is largely unknown in MRSA. Aim: This study aimed to understand antibacterial activity of GSH, its role in antibiotic susceptibility, and a potential antibacterial mechanism in clinical isolates of S. aureus. Materials and Methods: Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), checkerboard, time-killing, and bacterial killing assays were performed for 14 clinical isolates of S. aureus including 10 MRSA and two type strains (ATCC 700699 and 35556). Results: MIC and MBC levels for the clinical and type strains were 15 - 20 mM and 25 - 40 mM of GSH, respectively. Subinhibitory concentrations of GSH synergistically enhanced susceptibility of all tested-antibiotics, resulting in sensitizing all-tested S. aureus. Bacterial-killing produced by GSH-mediated acidity was significantly higher than that by hydrochloric acid-mediated acidity. Conclusion: Overall results concluded that GSH exhibited antibacterial activity on S. aureus regardless of antibiotic susceptibility and synergistically enhanced antibiotic susceptibility. Additionally, GSH-mediated acidity was one of the antibacterial mechanisms. These findings suggest that GSH may be a potential antimicrobial agent or adjuvant for the conventional anti-MRSA regimens.
文摘There are various bacteria living in this world. The most common one is Staphylococcus aureus. Almost everyone has heard of it. It is easy to find their habitats, such as hospitals, homes, parks, schools etc. Some of them are difficult to be eliminated because of drug-resistant mutations. Hence, lots of researchers devoted their efforts to eliminate them. This review illustrates the characteristics of the Staphylococcus aureus and the main threat of their drug-resistant strains, especially methicillin-resistant S. aureus. What’s more, the article also highlights the plight in the drug development.
文摘Methicillin-resistant Staphylococcus aureus(MRSA)strains are the essential cause of infections in communities and hospitals.The present study was conducted to determine the molecular typing of MRSA,isolated from hospitalized patients,using the double-locus sequence typing(DLST).In total,280 S.aureus isolated from clinical specimens by phenotypic(catalase,coagulase,DNase,oxacillin,vancomycin screening agar and antibiotic disk diffusion),and molecular methods(PCR for determining the mecA,vanA and nuc genes).The DLST and sequencing was performed for MRSA containing mecA.Out of 280 specimens,confirmed as Staphylococcus aureus(S.aureus),123(43.9%)strains were MRSA.The highest resistance toward the erythromycin(15μg),followed by ciprofloxacin(5μg),clindamycin(2μg),tetracycline(30μg),gentamicin(10μg)and rifampicin(5μg),was 98.3%,97.5%,94.3%,90.2%,83.7%and 41.4%,respectively.Also,the least resistance(0%)was observed in each of teicoplanin(30μg),linzolide(30μg),and vancomycin(30μg).All(100%)of MRSA strains had the mecA,and none of them have had the vanA.The results of DLST showed that the most common sequence types were BPH 2003 and 0217.The DLST type 18-32 was a significant cluster of MRSA.By sequencing MRSA and comparing the dominant types via the DLST,it is possible to establish the etiology of the disease in a much shorter time,and prevent the complications of the disease.Therefore,the combination of partial sequences of clfB and spa can serve as useful genetic markers for MRSA typing.It concluded that the MRSA in our region was relatively high,but no vancomycin resistance was found.The majority of the MRSA DLST type was 18–32.
文摘Objective:This study was conducted to update the prevalence of methicillin-resistant Staphylococcus aureus(MRSA) isolates among human clinical S.aureus isolates recovered from Northern Palestine,to evaluate the possible presence of vancomycin-Resistant S.aureus(VRSA) and vancomycin- intermediate resistant S.aureus strains(VISA) and to determine the antimicrobial susceptibilities of these clinical isolates.Methods:The in vitro activities of 11 antibiotics against 204 non-duplicate S.aureus isolates from clinical samples in North of Palestine were determined by the diskdiffusion method.These samples were isolated between June 2006 and December 2007.The minimum inhibitory concentration (MIC) of vancomycin for 115 methicillin resistant Staphylococcus aureus(MRSA) strains was carried out using the agar dilution method.Results:One hundred and fifteen(56.4%) of these isolates were MRSA and according to their antibiotic profile these are multidrug resistant(resistant to three or more non-p-lactam antibiotics). Ninety nine(43.6%) isolates were methicillin sensitive S.aureus(MSSA),forty four of MSSA isolates(44.4%) were multidrug resistant,while forty five(45.6%) were non multidrug resistant.Our results showed that the most common resistance(95.6%) was to penicillin.Two strains of MRSA have shown to be vancomycin- intermediate resistant,had MIC of 4μg/rnL and 8μg/mL and these vancomycin- intermediate resistant S.aureus strains(VISA) are resistant to all antibiotics tested.Conclusion:According to our information this is the first study report about VISA in Palestine.
文摘The purpose of this subject was to investigate molecular epidemiology of oxacillin-resistant Staphylococcus aureus (MRSA) isolated from hospitalized patients, and to survey the in vitro activity of teicoplanin, vancomycin and other 9 antibiotics against Staphylococcus species . MRSA were detected by oxacillin-NaCl-containing screen agar. The homology of nosocomial MRSA from ICU and RCU was determined by pulse-field gel electrophoresis. Agar diffusion, E test and agar dilution were used to compare the in vitro activity of teicoplanin and vancomycin against Staphylococcus spp from 2001 to 2003 at Peking Union Medical College Hospital. WHONET-5.3 software was used to analyze the antimicrobial susceptibility data. From 2001 to 2003, the prevalences of MRSA were 56.5%, 65.3%, 64.7%, respectively. PFGE found most of MRSA from ICU and RCU were closely related. All of S.aureus and S.epidimidis isolates were susceptible to teicoplanin and vancomycin from 2001 to 2003. However, 1 isolate of S.haemolyticus was resistant and 9 isolates intermediate to teicoplanin. The minimal inhibitory concentration of teicoplanin did not correlate well with zone diameter, when inoculum increased by 100 folds, the zone diameters of teicoplanin decreased more greatly than those of vancomycin. In 2002, severe outbreaks caused by MRSA strains had been found in ICU and RCU wards. Teicoplanin and vancomycin had good activity against clinical isolates of Staphylococci spp . Teicoplanin was less active than vancomycin against S.haemolyticus . Most of S.haemolyticus isolates were intermediate to teicoplanin. Antimicrobial susceptibility testing of teicoplanin was influenced by the diffusion speed in the agar and inoculum size.
文摘Introduction: Staphylococcus aureus is one of the most important agents involved in community and hospital-acquired infections. Due to the multi-drug resistance of strains to antibiotics, treatment to eradicate it is becoming more difficult and poses a global public health problem. Methodology: This was a cross-sectional study conducted from March to August 2020 in hospitals in the city of Douala, including all S. aureus isolates from diagnostic samples. Strain identification and antibiotic susceptibility testing were performed using the Vitek2 Compact<sup>TM</sup> (BioMerieux). Results: During the study period, 136 non-repetitive S. aureus strains were identified with a high frequency of methicillin-resistant S. aureus of 78.7%. The majority of the strains originated from the Douala General Hospital (66.9%) and was most frequently isolated from blood culture samples (55.1%). The study of biochemical characteristics showed that most of the strains identified had between 87% and 99% homology with the reference strain. The most active antibiotics were Quinupristin/Dalfopristin (94.2%), Linezolid (87.8%) and Vancomycin (84.2%). Methicillin resistance was associated with decreased susceptibility of S. aureus to other antibiotics such as Gentamycin (44.9%), Erythromycin (38.2%), Tetracycline (38.3%), Trimethoprim (21.4%), Ciprofloxacin (19.1%) and Levofloxacin (24.0%). Inducible MLSb and constitutive resistance phenotypes were identified with 26.7% and 22.8% respectively. Conclusion: The sensitivity of S. aureus strains differs from one antibiotic family to another, and remains good for molecules that are not available in our context. The high frequency of Methicillin-Resistant S. aureus shows the continuous progression of multi-resistant strains of S. aureus and their decreased sensitivity to usual antibiotics becomes more and more alarming.
文摘Staphylococcus aureus infection remains an increasing problem for higher morbidity and mortality in burn patients. We sought to determine the frequency of methicillin-resistant S. aureus (MRSA) in burn wound patients and study their drug resistance genes. Samples were collected (August 2010 to October 2011) from burn unit of Dhaka Medical College Hospital (DMCH), Bangladesh. MRSA was identified by conventional culture based methods. S. aureus was confirmed in 44.44% burn wound samples and 22.5% of the isolates were oxacillin resistant. All the S. aureus isolates were resistant to commonly used drugs like amoxicillin, azactam, erythromycin, azithromycin etc. and were sensitive to imipenem. The isolates were devoid of plasmid and the gene mecA, femA and IS431 were detected in their chromosomal DNA. Computational analysis of mecA gene sequence showed homology to S. aureus “penicillin binding protein 2a” (PBP-2a). The higher association of MRSA is in burn unit of DMCH, Bangladesh is alarming and with inappropriate antibiotic use, and the situation gets even complicated to treat. Therefore, the detection system and control practices for MRSA in DMCH should be improved in the hospital settings.
文摘The spread of antibiotic resistance, whether in the community or in the hospital, has recently become a major public health problem. Moreover, livestock seems to be a reservoir of resistant microorganisms such as porcine methicillin resistant Staphylococcus aureus (P-MRSA) whose carriage and transmission was mainly demonstrated in persons with occupational exposure to pigs. Much uncertainty remains about the public health implications of P-MRSA. To address concerns that exist regarding the zoonotic risk that pig carriers pose to breeders, the prevalence of P-MRSA in pigs and pig breeders was determined among 152 pig breeders in three regions of Cameroon. Materials and Method: Participants in this study came from Adamawa, Far North and Littoral regions of Cameroon. A total of 152 pig breeders or farm workers participated in this study. After having collected some social and cultural data with the aid of a questionnaire, nasal swabs were collected from pigs (n = 275) and their breeders using the standard collection procedures and placed in cooler containing cold accumulators. For each sample, microbiological assays were done as well as antibiotic susceptibility tests. Results: MRSA was isolated from 25 out of 275 pigs sampled (9.09%) and from 32 out of 152 (21.05%) pig breeders sampled;33 breeders (21.71%) were carriers of S. aureus including 32 MRSA and one MSSA. The prevalence of MRSA nasal carriage was 21.05% ± 6.48. A significant negative association between body protection and nasal carriage of MRSA (OR = 0.29, 95% CI [0.093;0.93];p = 0.04) was observed. In each region, similar strains of MRSA were isolated both in pigs and their breeders with the same antibiotic resistant profile. Conclusion: The prevalence of MRSA though not high compared to European countries warrants further research as data on this zoonosis is scarce in our context. As such, transmission of MRSA from pigs to pig breeders or vice-versa constitutes a real danger, and this relationship may be a starting point for MRSA contamination in the community. Moreover, proper use of body protections and antibiotic medications as recommended will be a better protective measure against nasal MRSA carriage.
文摘Epidemiological surveillance for microbes is currently based on either agar culture followed by identification, or genetic amplification. Both techniques are highly skilled-labor intensive, costly, and must be done in central laboratories. The Defined Substrate Utilization®(DSU®) format provides an epidemiological series of specific screening formulations that obviate these limitations. All reagents are present in optimized stable powder form in a test tube—add water, inoculate, and incubate. A specific color change provides a sensitive and specific detection of the target microbe. Two DSU®methods for Staphylococcus aureus (S. aureus) are presented: aureusAlert®for all S. aureus and EPI-M®for methicillin-resistant S. aureus (MRSA). Both aureusAlert®and EPI-M®had a detection level of 20 colony forming units (CFU) in 18 hours. aureusAlert®and conventional methods agreed 93.6% and EPI-M®and conventional methods agreed 94.1%. DSU®and conventional methods showed the same specificity.