2017年安徽省某三甲医院细菌耐药性监测

目的 了解铜陵市人民医院2017年临床分离细菌对抗菌药物的耐药状况。方法 对2017年1-12月临床分离菌采用纸片扩散法(KB)进行药敏试验，按CLSI 2017年版标准判读药敏试验结果，采用WHONET 5.6软件进行数据分析。结果 临床分离细菌共3436株，其中革兰阳性菌719株，占20.9%；革兰阴性菌2717株，占79.1%。耐甲氧西林金黄色葡萄球菌(MRSA)和耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)的检出率分别为23.8%和72.3%，耐甲氧西林株对β-内酰胺类抗生素和其他测试抗菌药物的耐药率显著高于甲氧西林敏感株，未发现对万古霉素和替考拉宁耐药的葡萄球菌。粪肠球菌对青霉素、氨苄西林和呋喃妥因的耐药率较低，屎肠球菌对氯霉素的耐药率较低，5.3%屎肠球菌对万古霉素耐药。大肠埃希菌、克雷伯菌属(肺炎克雷伯菌和产酸克雷伯菌)和奇异变形菌中ESBLs的检出率分别为41.4%、50.7%和19.4%。肠杆菌科细菌中克雷伯菌属和沙雷菌属对碳青霉烯类抗生素耐药率较高，分别为37.5%和36.0%，其他菌属的耐药率低于3%。鲍曼不动杆菌对亚胺培南和美罗培南的耐药率分别80.3%和79.1%；铜绿假单胞菌对亚胺培南和美罗培南的耐药率分别为29.7%和28.4%。肺炎克雷伯菌、鲍曼不动杆菌和铜绿假单胞菌中广泛耐药株的检出率分别为31.3%(171/546)、0.6%(3/508)和0.7%(3/416)。结论 本院革兰阴性菌呈增多趋势，尤其广泛耐药的肺炎克雷伯菌应引起高度关注，做好细菌耐药性监测，加强临床抗菌药物的合理使用和医院感染控制。     

从食品中检出多种肠球菌及大肠杆菌的报告

[目的]了解供机食品的卫生状况，分析鉴定目的菌的特性。[方法]依据相关国家标准及VITEK操作手册对病原微生物进行检验和鉴定。[结果]从1份供机食品-豇豆中同时检出屎肠球菌、坚韧肠球菌及大肠杆菌，分别具有这3种病原菌的典型培养特性、菌体特征及生化特性。[结论]日常工作中应重视对多种病原菌的检验及加强对供机食品从原料到成品的全过程卫生监控，以保障工作人员及乘客的生命安全。     

不同培养基对肠球菌检出率的影响

用pH9.6葡萄糖肉汤、6.5％NaCl琼脂平板、3％—5％羊血琼脂平板三种不同培养基,从同一份样品中分离肠球菌,检出率有显著差别。pH9.6葡萄糖肉汤对检样选择性增菌后,再用6.5％NaCl琼脂平板分离肠球菌,其检出率明显高于现正普遍用于肠球菌初代分离的3％～5％血琼脂平板(P<0.05),也高于单纯使用6.5％NaCl琼脂平板(P<0.05);后两者间无显著差别(P>O.05)。属中种的构成在不同培养基上检出情况也不同。 关键词:培养基 肠球菌 检出率 肠球菌广泛存在于自然界,是水、空气、尘     

Effect of lysed Enterococcus faecalis FK-23 (LFK) on allergen-induced peritoneal accumulation of eosinophils in mice

BACKGROUND: The interest in anti-allergy immunoregulation by lactic acid bacteria has been growing for the last few decades. There is some evidence to suggest that lysed Enterococcus faecalis FK-23 (LFK) could relieve the clinical symptoms of pollinosis. However, the mechanism responsible for this phenomenon remains unknown. OBJECTIVE: To identify the effect of LFK, a lysozyme treated and heat-killed preparation from the lactic acid bacteria Enterococcus faecalis FK-23 strain, on allergen-induced eosinophil accumulation. METHODS: BALB/c mice were sensitized with ragweed pollen extract, and peritoneal accumulation of eosinophils was induced. A total of 60 mg (0.5 mL) LFK was orally administered to the experimental mouse every day during 21 days of the sensitization period. In addition, LFK 4 mg, 25 mg and 60 mg (each 0.5 mL) were also orally administered to a mouse of each group every day for 21 days. Saline was fed in a dose of 0.5 mL/mouse per day for the same duration as a control. RESULTS: Compared with control mice, LFK-treated mice exhibited decreased ragweed pollen allergen-induced peritoneal accumulation of eosinophils (P = 0.013), which showed a tendency to be in a dose-dependent fashion (P = 0.14). CONCLUSION: The results provide laboratory evidence of the role for LFK, a lactic acid bacteria preparation, in combating eosinophil accumulation.     

Comparison of multiple-locus variable-number tandem repeat analysis and pulsed-field gel electrophoresis in a setting of polyclonal endemicity of vancomycin-resistant Enterococcus faecium.

In order to assess whether multiple-locus-variable number tandem repeat analysis (MLVA) could replace pulsed-field gel electrophoresis (PFGE) for genotyping vancomycin-resistant isolates of Enterococcus faecium (VREF), this study compared the typeability, discriminatory power, concordance and costs of these methods for VREF isolates obtained from patients, environmental samples and the hands of healthcare workers (HCWs) in a medical intensive care unit (ICU) where VREF was endemic. Over a 58-day period, 393 VREF isolates (373 vanA, one vanA/B, 19 vanB) were cultured from patient rectal swabs (n = 76), the environment (n = 270) and the hands of HCWs (n = 47). PFGE was able to divide 358 (91.1%) isolates into 19 PFGE types (>six bands different) and 24 subtypes (one to three bands different). MLVA was able to type 391 (99.5%) isolates into 11 genotypes. The discriminatory power of PFGE subtypes was 83%, as compared to 68% for MLVA. Concordance between the two methods, based on matched or mismatched MLVA types and PFGE types or subtypes, was 67.5% and 82.8%, respectively. Using PFGE, 13 isolates could be genotyped in 3 days; MLVA genotyped 94 isolates in 2 days. For both methods, the estimated costs were Euro 7 ($10)/isolate. PFGE and MLVA produced highly concordant results when assigning genotypes to nosocomial VREF isolates. MLVA was faster, but PFGE subtyping was more discriminatory.     

Comparison of agar-based media for primary isolation of glycopeptide-resistant enterococci

Objective: To compare four vancomycin-containing agar media for the isolation of glycopeptide-resistant enterococci (GRE) from clinical fecal specimens: kanamycin-aesculin-azide (KAA) agar; bile-aesculin-polymixin (BAP) agar; aztreonam-amphotericin blood (CBAA) agar; and neomycin blood (CBN) agar.
Methods: Fecal specimens from 125 patients were inoculated onto each medium. Media were examined for enterococci after incubation for up to 48 h. Enterococci were identified to species level, and glycopeptide phenotypes were determined by measuring minimum inhibitory concentrations of vancomycin and teicoplanin.
Results: GRE were isolated from 44/125 samples. Enterococcus faecalis and Enterococcus faecium isolates, expressing glycopeptide resistance of the VanA or VanB phenotypes, were recovered from 27/33 (82%) specimens on BAP medium, 26/33 (79%) on KAA medium, and 21/33 (64%) on CBN and CBAA media. Enterococcus gallinarum and Enterococcus casseliflavus isolates expressing low-level glycopeptide resistance (VanC phenotype) were recovered from 14/15 (93%) specimens on CBAA medium, 7/15 (47%) on KAA and CBN media, and 6/15 (40%) on BAP medium.
Conclusions: The media tested in this study, with the exception of CBN medium, detected at least 75% of patients colonized by GRE. Further development of BAP, CBAA and KAA media is warranted to improve growth and selectivity.     

Genetic relatedness and antimicrobial resistance determinants among clinical isolates of enterococci from Cuba

This study describes the genetic relationships and antimicrobial resistance determinants found among 99 clinical isolates of enterococci from 15 different hospitals in Cuba. Pulsed-field gel electrophoresis SmaI analysis demonstrated a high degree of genetic diversity. A limited number of multiresistant Enterococcus faecalis clones, showing resistance to three or more families of antimicrobial agents, were detected simultaneously in different institutions, suggesting inter-hospital circulation of selected clones, and/or selection of particular clones following their introduction into the hospital environment. Antimicrobial resistance determinants, including erm(B), aac(6')-aph(2'), aph(3'), ant(6), vanB (E. faecalis) and vanA (Enterococcus faecium) were detected by PCR in various isolates.     

Infective endocarditis in Greece: a changing profile. Epidemiological, microbiological and therapeutic data

The epidemiology, and clinical and microbiological spectrum, of infective endocarditis (IE) in Greece was analysed in a prospective 4-year study in a tertiary hospital and a heart surgery centre in Athens. In total, 101 cases of IE (71 men, 30 women, aged 54.4 +/- 17.1 years) were studied, with a follow-up period of 3 months. Seventy-seven cases were definite and 24 possible; 59 involved native valves (native valve endocarditis; NVE), 31 prosthetic valves (prosthetic valve endocarditis; PVE), of which nine were early and 22 late, and 11 permanent pacemakers (pacemaker endocarditis; PME). There was a predominant involvement of aortic (48/101) and mitral (40/101) valves. Seven patients had rheumatic valvular disease, two had mitral valve prolapse, and eight had a previous history of IE. Thirteen and six patients had undergone dental and endoscopic procedures, respectively. In 13 patients, intravenous catheters were used within the 3 months before diagnosis of IE. There were three intravenous drug users among the patients. Staphylococcus aureus was the most important pathogen, isolated in 22% of cases, followed by viridans streptococci (19%) and coagulase-negative staphylococci (16%). Enterococcus spp. were responsible for 3%, HACEK group for 2%, and fungi for 6% of cases. Viridans streptococci were the leading cause of NVE (29%), Staphylococcus epidermidis of PVE (16%), and S. aureus of PME (54.5%). Six of 22 S. aureus and ten of 16 S. epidermidis isolates were methicillin-resistant. Surgical intervention, including total pacemaker removal, was performed in 51.5% of patients. Overall mortality was 16%, but was 29% with PVE, and was significantly higher with medical than with combined surgical and medical therapy (24.5% vs. 8%). Compared with previous studies, there were changing trends in the epidemiology, microbiology, treatment and prognosis of IE in Greece.     

Nosocomial vs. community-acquired infective endocarditis in Greece: changing epidemiological profile and mortality risk

Current epidemiological trends of infective endocarditis (IE) in Greece were investigated via a prospective cohort study of all cases of IE that fulfilled the Duke criteria during 2000-2004 in 14 tertiary and six general hospitals in the metropolitan area of Athens. Demographics, clinical data and outcome were compared for nosocomial IE (NIE) and community-acquired IE (CIE). NIE accounted for 42 (21.5%) and CIE for 153 (78.5%) of 195 cases. Intravenous drug use was associated exclusively with CIE, while co-morbidities (cardiovascular disease, diabetes mellitus, chronic renal failure requiring haemodialysis and malignancies) were more frequent in the NIE group (p <0.05). Prosthetic valve endocarditis (PVE) predominated in the NIE group (p 0.006), and >50% of NIE cases had a history of vascular intervention. Coagulase-negative staphylococci and enterococci were more frequent in cases of NIE than in cases of CIE (26.2% vs. 5.2%, p <0.01, and 30.9% vs. 16.3%, p 0.05, respectively). Enterococci accounted for 19.5% of total IE cases and were the leading cause of NIE. Staphylococcus aureus IE was hospital-acquired in only 11.9% of cases. In-hospital mortality was higher for NIE than for CIE (39.5% vs. 18.6%, p 0.02). Cardiac failure (New York Heart Association grade III-IV; OR 13.3, 95% CI 4.9-36.1, p <0.001) and prosthetic valve endocarditis (OR 3.7, 95% CI 1.3-10.6, p 0.01) were the most important predictors of mortality.     

1000株肠球菌耐药性分析

目的 测定1999年1月至2002年12月临床分离的1000株肠球菌对11种抗生素的敏感性现状，为临床合理选药提供客观实验依据。方法 菌株经Vitek和Microscan及常规方法鉴定，按照NCCLS推荐的纸片扩散法和判断标准进行药敏试验，并用WHONET5软件进行分析，用琼脂稀释法测定菌株的MIC值。结果 粪肠球菌和屎肠球菌分离率分别占肠球菌的56．0％和41．7％；居前4位的标本依次是尿液(68．7％)、痰液(15．3％)、血液(8．3％)、脓性分泌物(6．4％)。纸片法测定结果表明粪肠球菌和尿肠球菌对万古霉素、呋喃妥因、氯霉素、红霉素、四环素、青霉素、氨苄西林、亚胺培南、高浓度庆大霉素以及环丙沙星的耐药率分别为2．2％、3．3％；10．0％、12．7％；54．5％、73．8％；82．3％、96．8％；43．3％、44．7％；17．1％、85．9％；14．9％、73．9％；13．8％、72．5％；46．0％、55．4％；34．8％、66．9％。MIC值测定结果表明头孢硫脒对粪肠球菌MIC50和MIC90分别为2和16mg／L；对屎肠球菌为16和128mg/L。万古霉素对粪肠球菌、屎肠球菌MIC50、MIC90均为2和4mg／L。结论 肠球菌对万古霉素耐药率低，头孢硫脒与其它药物相比对粪肠球菌体外活性较强，对屎肠球菌活性相当，肠球菌对其余9种抗菌药物耐药率有逐年增加的趋势。