Antibiotic Susceptibility of Bacterial Strains Isolated from Patients with Community-Acquired Urinary Tract Infections in France

 The aim of this study was to determine the distribution and antibiotic susceptibility patterns of bacterial strains isolated from adults with community-acquired urinary tract infections (UTI) in France. From December 1996 to March 1997, each of 15 private laboratories in France consecutively collected about 80 non-duplicate strains isolated from adult outpatients with UTI, including patients receiving care at home, and tested their susceptibility by the disk diffusion test. A total of 1160 strains were collected: 1031 gram-negative bacilli, including Escherichia coli (n=865), Proteus mirabilis (n=68) and Klebsiella spp. (n=40), and 129 gram-positive cocci, including Staphylococcus aureus (n=16), other staphylococci (n=25), group B streptococci (n=25) and enterococci (n=63). In the case of 430 bacterial isolates, the patients had either been hospitalised in the last 6 months or received antibiotic treatment in the last 3 months. The antibiotic susceptibility rates for Escherichia coli were: amoxicillin (58.7%), amoxicillin-clavulanic acid (63.3%), ticarcillin (61.4%), cephalothin (66.8%) cefuroxime (77.6%), cefixime (83.6%), cefotaxime (99.8%), ceftazidime (99%), nalidixic acid (91.9%), norfloxacin (96.6%), ofloxacin (96.3%), ciprofloxacin (98.3%), cotrimoxazole (78.2%), fosfomycin (99.1%) and gentamicin (98.4%). Of the Enterobacteriaceae, five strains produced an extended-spectrum beta-lactamase. Methicillin resistance was detected in nine Staphylococcus aureus isolates. The most important findings were two extended-spectrum, beta-lactamase-producing and three methicillin-resistant Staphylococcus aureus strains isolated from patients who had not been hospitalised in the last 6 months or taken antibiotics in the last 3 months. The findings indicate that these strains can spread within the community; therefore, monitoring antibiotic susceptibility of bacteria isolated in the community appears to be mandatory.     

Association of Borderline Oxacillin-Susceptible Strains of Staphylococcus aureus with Surgical Wound Infections

Staphylococcus aureus isolates which produce type A staphylococcal β-lactamase have been associated with wound infections complicating the use of cefazolin prophylaxis in surgery. To further evaluate this finding, 215 wound isolates from 14 cities in the United States were characterized by antimicrobial susceptibility and β-lactamase type and correlated with the preoperative prophylactic regimen. Borderline-susceptible S. aureus isolates of phage group 5 (BSSA-5), which produce large amounts of type A β-lactamase and exhibit borderline susceptibility to oxacillin, comprised a greater percentage of the 120 wound isolates associated with cefazolin prophylaxis than they did of the 95 isolates associated with other prophylactic regimens (25% versus 12.6%, respectively; P < 0.05). In contrast, methicillin-resistant S. aureus isolates were distributed evenly between the two groups (8.3% versus 11.6%, respectively). In vitro assays demonstrated that cefazolin was hydrolyzed faster by BSSA-5 strains than by other β-lactamase-producing, methicillin-susceptible strains (1.54 versus 0.50 μg/min/10⁸ CFU, respectively; P < 0.0001). These data demonstrate that BSSA-5 strains are a distinct subpopulation of methicillin-susceptible S. aureus which frequently cause deep surgical wound infections. Cefazolin use in prophylaxis is a risk factor for BSSA-5 infection.     

Increasing Multidrug Resistance in Helicobacter pylori Strains Isolated from Children and Adults in Mexico

The susceptibilities to three antimicrobials of 195 Helicobacter pylori strains isolated from Mexican patients is reported; 80% of the strains were resistant to metronidazole, 24% were resistant to clarithromycin, and 18% presented a transient resistance to amoxicillin. Resistance to two or more antimicrobials increased significantly from 1995 to 1997.     

广州地区2003—2007年499株铜绿假单胞菌的耐药性分析

目的了解广州地区铜绿假单胞菌对常用抗菌药物的耐药状况,以指导临床合理选用抗生素。方法收集广州市7家三甲医院2003—2007年分离的499株铜绿假单胞菌,利用VITEK-32全自动微生物鉴定系统对所有收集的菌株进行种属鉴定,参照美国临床和实验室标准化协会（CLSI）推荐的方法,分别采用K—B法和琼脂稀释法进行药敏试验,用WHONET5．4软件分析铜绿假单胞菌的耐药性,用SPSS11．5软件进行统计分析。结果499株铜绿假单胞菌其抗生素耐药率依次为庆大霉素（42．0％）、阿米卡星（36．6％）、亚胺培南（32．8％）、头孢吡肟（28．3％）、头孢他啶（27．1％）、美罗培南（21．4％）、氨曲南（20．5％）、哌拉西林（8．8％）、哌拉西林／三唑巴坦（8．3％）、左旋氧氟沙星（8．1％）和环丙沙星（7．6％）;2003—2007年5年期间铜绿假单胞菌对亚胺培南的耐药率分别是27．7％、25．0％、31．6％、35．2％和34．3％,对美罗培南的耐药率分别是22．2％、21．O％、21．2％、19．7％和24．5％。结论2003—2007年广州地区铜绿假单胞菌整体耐药现象严重,对氨基糖苷类、碳青霉烯类和头孢菌素类抗生素高度耐药,仅对喹诺酮类和青霉素类抗生素较为敏感。因而加强其耐药性监测不仅可以指导临床合理选用抗菌药物．而且还能为临床提供最新的流行病学和耐药性变迁资料。     

371株鲍曼不动杆菌的临床耐药状况

本文对临床分离出的鲍曼不动杆菌的耐药性进行回顾性分析,为临床经验性治疗首选抗生素提供依据。对我院2006年10月至2009年10月分离出的371株鲍曼不动杆菌,用VITEK32细菌鉴定及药敏分析系统进行细菌鉴定和药敏试验,结合K-B法作补充对照。在分离出的371株鲍曼不动杆菌中,以老年煤工尘肺患者及重症监护病人集中的科室比率较高,在呼吸道标本中的构成比高于其他种类的标本。该菌对亚胺培南、哌拉西林/他唑巴坦,氨苄西林/舒巴坦的耐药率相对较低,各为5.0%、19.5%、19.5%。对复方新诺明、妥布霉素、左氧氟沙星、庆大霉素、环丙沙星、头孢吡肟、头孢他啶的耐药率分别为32.7%、43.2%、44.6%、44.9%、47.3%、53.8%、56.5%。对头孢曲松、氨曲南、氨苄西林、呋喃妥因、头孢唑啉有较高的耐药性,耐药率均在90%以上。鲍曼不动杆菌对多种抗生素耐药现象严重,根据药敏试验合理应用抗生素十分重要。     

Characterization of Slackia exigua Isolated from Human Wound Infections,Including Abscesses of Intestinal Origin

Eleven clinical strains isolated from infected wound specimens were subjected to polyphasic taxonomic analysis. Sequence analysis of the 16S rRNA gene showed that all 11 strains were phylogenetically related to Slackia exigua. Additionally, conventional and biochemical tests of 6 of the 11 strains were performed as supplementary methods to obtain phenotypic identification by comparison with the phenotypes of the relevant type strains. S. exigua has been considered an oral bacterial species in the family Coriobacteriaceae. This organism is fastidious and grows poorly, so it may easily be overlooked. The 16S rRNA gene sequences and the biochemical characteristics of four of the S. exigua strains isolated for this study from various infections indicative of an intestinal source were almost identical to those of the validated S. exigua type strain from an oral source and two of the S. exigua strains from oral sources evaluated in this study. Thus, we show for the first time that S. exigua species can be isolated from extraoral infections as well as from oral infections. The profiles of susceptibility to selected antimicrobials of this species were also investigated for the first time.In recent years, there have been reports that Slackia exigua is a poorly growing pathogen in periodontitis and periapical infections (1, 5, 8, 20, 23, 27). This bacterium was originally classified as Eubacterium exiguum in 1996 (20) and was reclassified as S. exigua in 1999 (27). S. exigua is a Gram-positive, non-spore-forming, nonmotile, and strictly anaerobic bacillus that has been considered an oral asaccharolytic bacterial species in the family Coriobacteriaceae. The species has proven to be difficult to culture and is unreactive in conventional biochemical tests (27).S. exigua has frequently been isolated from periradicular lesions (8, 13, 22), in addition to other oral sites (9, 18, 28). In particular, S. exigua has been found in infected necrotic pulps and periradicular lesions (8, 22). These facts suggest that this species may play a pathogenic role in oral infectious diseases, including pulpal infections that spread to the periradicular tissues. In addition, S. exigua has been reported to be associated with clinical indicators of periodontal disease (1). However, S. exigua was isolated from five infections clearly of intestinal origin during our investigation of the microbiology of human wound infections and abscesses (6). Therefore, the current study was carried out to see if there are any significant differences in the characteristics of clinical isolates of oral and intestinal origin.In this report, we provide a profile of the role of the bacterium S. exigua in various wound infections. We have isolated S. exigua strains not only from oral infections but also from various extraoral wound infections and abscesses. The S. exigua isolates were characterized genotypically and phenotypically. To our knowledge, this is the first report of the isolation and extensive characterization of S. exigua from human infections other than oral infections. It is also the first time that its antimicrobial susceptibility has been studied.     

Blood Stream Infections in Allogeneic Hematopoietic Stem Cell Transplant Recipients: Reemergence of Gram-Negative Rods and Increasing Antibiotic Resistance

Blood stream infections (BSI) are a well-known cause of morbidity and mortality in hematopoietic stem cell transplant (HSCT) patients. The aim of this study was to analyze etiology and microbial resistance of BSI in patients undergoing allogeneic HSCT in a single center over a 4-year period (2004-2007). There were 168 episodes of BSI in 132 patients (median 10 days after HSCT) and 182 pathogens were isolated. Gram-positive bacteria (GPB) accounted for 57% of 182 isolates. Gram-negative rods (GNR) for 37% and fungi for 6%. All patients received routine fluoroquinolone prophylaxis. There was a significant decrease in GPB/GNR ratio over time, from 2.4 in 2004 to 1 in 2007 (P = .043). Among GPB, staphylococci decreased from 37 of 68 (64%) in 2004-2005 to 8 of 35 (23%) in 2006-2007 (P < .002). The Enterococcus faecalis/E. faecium ratio decreased from 4.5 in 2004 to 0.33 in 2007 (P = .006), whereas the total number of enterococcal strains per year did not change. The incidence of Escherichia coli among GNR increased from 3 of 15 (20%) in 2004 to 13 of 21 (62%) in 2007 (P = .003). Fluoroquinolone-resistance was common, both among GPB and GNR (81% and 74%, respectively). Mortality rate at 7 days after BSI was 11% (19 of 168), reaching 39% for Pseudomonas aeruginosa BSI (7 of 18). BSI remains a frequent and potentially life-threatening complication of allogeneic HSCT, the causative organism influencing 7- and 30-day mortality rate. BSI etiology may change rapidly, requiring implementation of new empirical-therapy schemes.     

广州地区肺炎住院患儿感染肺炎链球菌的血清型分布及耐药性研究

目的了解广州地区肺炎住院的患儿感染肺炎链球菌的耐药性及血清型分布情况。方法用吸痰法采集患儿痰标本进行涂片，革兰氏染色镜检，合格痰标本划线接种血平板，用E-test法检测分离到的肺炎链球菌对青霉素、阿莫西林、头孢曲松、头孢呋辛、亚胺培南、氧氟沙星、万古霉素、红霉素和克林霉素9种药物的耐药性，采用K-B法检测四环素、复方新诺明的耐药性，并采用荚膜肿胀技术对分离到的79株肺炎链球菌进行血清分型。结果79株肺炎链球菌中青霉素耐药肺炎链球菌（PRSP）11．4％，青霉素中介肺炎链球菌（PISP）77．2％，青霉素敏感肺炎链球菌（PSSP）11．4％，对红霉素、克林霉素的耐药率分别为100％和93．7％，对阿莫西林、氧氟沙星、万古霉素的耐药率均为0，对头孢曲松、头孢呋辛、亚胺培南的耐药率分别为3．8％、72．2％、2．5％。79株肺炎链球菌中只有1株PSSP仅对红霉素耐药．78株肺炎链球菌对两种以上药物耐药．多重耐药率为98．7％（78／79），同时对克林霉素、红霉素、四环素、复方新诺明耐药的菌株65株，占82．3％（65／79）。79株肺炎链球菌血清型分别为19F（70．9％），23F（16．5％），6B（5．1％），4（2．5％），15B（2．5％），不能分型（2．5％），7价疫苗涵盖率为94．9％（75／79）。结论广州地区肺炎住院患儿肺炎链球菌对大环内脂类抗生素红霉素和林可酰胺类抗生素克林霉素耐药情况严重，对二代头孢菌素头孢呋辛耐药率居高，临床治疗儿童肺炎链球菌感染的肺炎应首选阿莫西林和三代头孢菌素。7价疫苗覆盖率高。预防儿童肺炎链球菌感染所致的肺炎，采用7价疫苗可以达到很好效果。     

Molecular Characterization and Prophage DNA Contents of Streptococcus agalactiae Strains Isolated from Adult Skin and Osteoarticular Infections

Skin and osteoarticular infections (SKI and OAI, respectively) account for almost one-third of Streptococcus agalactiae infections in nonpregnant adults. We evaluated the genetic diversity and phylogeny of 58 S. agalactiae strains responsible for adult SKI or OAI and of 61 S. agalactiae strains from cases of adult human colonization (HCol) by serotyping and multilocus sequence typing (MLST). We also assessed the prophage DNA content of the genomes of these strains by a PCR-based method. We found that 63% of SKI and 56% of OAI occurred in people aged 55 years and over. Overall, 71% of SKI strains were of serotype Ia or V, and 91% of OAI strains were of serotype Ia, III, or V. Strains of clonal complexes 1 and 23 (CC1 and CC23) were associated with 79% of SKI cases and 62% of OAI cases. Seven groups of strains, groups A, B, C, D, E, F, and G, were obtained by performing a hierarchical analysis on the basis of prophage DNA-PCR data. We found that 85% of CC1 strains clustered in DNA prophage group D, the group with the highest prophage DNA content (average, 4.4; average of absolute deviations [AVEDEV], 0.9). The CC23 strains displayed the greatest diversity in prophage DNA fragment content, but 47% of CC23 strains clustered in group B, which also had a high average prophage DNA content per strain (average, 2.3; AVEDEV, 0.6). Many (65%) of the OAI strains were in prophage DNA group D, whereas 83% of the SKI strains were in prophage DNA groups B and D. These data suggest that S. agalactiae strains from CC1 and CC23 may be subject to particular transduction mechanisms in gene recombination, rendering them particularly capable of invading the skin, bone, or joints in adults.Streptococcus agalactiae was initially described in 1887 as an animal pathogen causing bovine mastitis (36). Since the 1960s, when human vaginal carriage of S. agalactiae was first documented, S. agalactiae has frequently been linked to neonatal infections and this bacterium has become the leading neonatal pathogen in developed countries (10, 13, 22, 23, 27, 34). S. agalactiae was rarely isolated from nonpregnant adults until 2 decades ago, when such infections began to be reported, particularly for the elderly and for individuals with underlying conditions such as diabetes mellitus, cancer, and a compromised immune system (4, 15, 37, 40-42). However, such infections have been reported even for adults without a known susceptibility factor (29, 33). Many case reports of clinical skin and osteoarticular infections (SKI and OAI, respectively) due to S. agalactiae in adults have been published in recent years, with these infections accounting for at least one-third of the reported cases of S. agalactiae infection in adults (41, 42).Many genetic markers have been identified as associated with S. agalactiae clones specifically responsible for meningitis in neonates. Indeed, most of the S. agalactiae strains isolated from the cerebrospinal fluid of neonates belong to clonal complex 17 (CC17) and have particular mobile genetic elements, such as the group II intron GBSi1 (2) and particular prophage DNA fragments (47). No particular markers or virulence factors of S. agalactiae strains have been associated with any other disease.Phages are important vehicles for horizontal gene exchange within bacterial populations and account for much of the genomic variation observed within bacterial species (8, 11, 28). Temperate phages affect bacterial fitness by modifying anchor points for genomic rearrangements, by disrupting genes, by protecting against lytic infection, by lysing competing strains through prophage induction, and by introducing new fitness factors (8, 19). Prophage acquisition, accounting for much of the molecular diversity of the Streptococcus pyogenes genome, rendered some of the strains of this species virulent through the acquisition of phage-encoded virulence factors and enhanced pathogen survival by improving resistance to host defenses under certain circumstances (1, 9). Little is currently known about S. agalactiae phages. They were first isolated in 1969 (39), and more-recent analyses of sequenced S. agalactiae strains have revealed the presence of abundant regions resembling prophages (16, 44, 45). We recently induced phages from S. agalactiae strains of various phylogenetic lineages, characterized them molecularly, and determined their lytic activities (12). The various molecular phage groups were found to correspond to particular strain lineages, with specific morphological features and lytic activities, suggesting a role for phage-mediated horizontal gene transfer in the evolution of the species and the emergence of lineages with a more specific role in particular diseases.In this study, we characterized S. agalactiae strains isolated from skin and osteoarticular infections in adults, using serotyping and multilocus sequence typing (MLST) to determine the phylogenetic relationships and molecular features of the strains involved through comparison with the characteristics of strains involved in human colonization (HCol). We used a PCR-based method recognizing S. agalactiae prophages to determine the prophage content of strain genomes (12). The genetic relationships between prophage DNA regions of strains were determined by hierarchical analysis. Correlations between the prophage DNA content, the clinical circumstances of isolation, and the phylogenetic position of S. agalactiae strains were investigated.     

血培养常见菌株的分布及金黄色葡萄球菌耐药性的分析

目的调查同济医院2006年1月至2008年12月血培养中常见非重复分离菌株的构成;分析金黄色葡萄球菌对常用抗菌药物的耐药性。方法采用WHONET5．4软件分析连续3年血培养中的非重复分离菌株的分布;采用K-B纸片法测定金黄色葡萄球菌对常用抗菌药物的敏感性。结果2006年1月至2008年12月共分离细菌1336株,其中革兰阳性球菌占58．5％（781／1336）、革兰阴性杆菌占37．2％（497／1336）、真菌占4．27％（57／1336）。分离的前10位菌株依次为凝固酶阴性葡萄球菌（CNS,40．42％）、大肠埃希菌（13．47％）、肠球菌属（5．54％）、克雷伯菌属（4．94％）、金黄色葡萄球菌（4．34％）、草绿链球菌（4．34％）、真菌（4．27％）、沙门菌属（3．59％）、铜绿假单胞菌（3．29％）、嗜麦芽窄食单胞菌（3．14％）。金黄色葡萄球菌共58株,其中甲氧西林耐药金黄色葡萄球菌（methicillinresistantStaphylococcusoltl-eus。MRSA）占44．8％（26／58）。MRSA对头孢菌素类、氨苄西林／舒巴坦、红霉素、克林霉素、复方新诺明、庆大霉素和左氧氟沙星、磷霉素、利福平耐药率明显高于甲氧西林敏感的金黄色葡萄球菌（methicillin—susceptibleStaphylococcuso,uFeus,MSSA）,且差异具有统计学意义（P〈0．001）。未发现对万古霉素和替考拉宁不敏感的菌株。结论本院血培养分离株中,凝固酶阴性葡萄球菌仍占据第一位。金黄色葡萄球菌占分离菌株第五位,其中MRSA检出率较高,且耐药性严重。MRSA病区的分布及耐药谱分析提示可能存在MRSA的克隆传播。     

Diversity of Staphylococcus aureus Strains Isolated from Two European Regions with Different Prevalences of Methicillin Resistance

The genodiversity of Staphylococcus aureus isolates from the Nottingham region of the United Kingdom was compared with isolates from the Freiburg region of Germany. The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) isolates was higher in Nottingham than in Freiburg. In patients from Nottingham hospitals, 80% of MRSA isolates were classical epidemic MRSA-15, but genotypic variants of epidemic MRSA-15 comprised 72% of isolates from Nottingham community-based patients. In contrast, MRSA isolates from Freiburg showed greater diversity, but 47% and 23% of isolates, respectively, belonged to two predominant MRSA genotypes found in isolates from both hospitalised and community-based patients. The results suggest that genodiversity becomes increasingly more confined in settings with a higher frequency and longer duration of MRSA prevalence. Electronic Publication     

Cytotoxic Effects of Klebsiella oxytoca Strains Isolated from Patients with Antibiotic-Associated Hemorrhagic Colitis or Other Diseases Caused by Infections and from Healthy Subjects

Antibiotic-associated hemorrhagic colitis (AAHC) is associated with Klebsiella oxytoca. This study analyzed whether cytotoxic properties are linked to specific subtypes of K. oxytoca. Klebsiella isolates from stools of AAHC patients, healthy carriers, and diarrhea patients as well as from infections of other organs were investigated. Cytotoxic effects on human epithelial cells were limited to the species K. oxytoca and were not detectable for any other Klebsiella species. Isolates from AAHC patients and from stools showed the highest proportion of cytotoxic strains. Urinary or respiratory tract isolates exhibited no cytotoxicity. Macrorestriction profiling of strains revealed no genetic relationships of AAHC isolates or the cytotoxic phenotype but identified that different K. oxytoca strains with different cytotoxic behaviors may be prevalent in the same AAHC patient. Under laboratory conditions, cytotoxicity was maximally effective after exponential bacterial growth and then declined despite the continued viability of K. oxytoca cells in culture. Given its capacity to induce AAHC and that a high proportion of stool isolates tested cytotoxin positive, we argue that K. oxytoca should be considered an opportunistic pathogen if detected in stools. The ability to induce disease after antibiotic treatment most likely represents an overgrowth of the toxin-producing bacterium due to an alteration of the normal colonic microflora.Antibiotic-associated colitis (AAC) is a frequent adverse effect observed when the normal bacterial flora is altered due to antibiotic therapy. Most cases of AAC are caused by infection by and extensive growth of Clostridium difficile, leading to pseudomembranous colitis. A special form of AAC is antibiotic-associated hemorrhagic colitis (AAHC), which was first described in 1978 (21) and has since been ascribed specific clinical, endoscopic, histopathological, and microbiological characteristics (9, 10). AAHC is not associated with C. difficile and was only recently shown to be caused by Klebsiella oxytoca (9, 10). AAHC is typically observed after a brief therapy with penicillins, with a sudden onset of bloody diarrhea often in combination with severe abdominal cramps, which often requires hospitalization. The key features of AAHC upon endoscopy are mucosal hemorrhage and mucosal edema, usually with segmental distribution, commonly affecting the ascending colon and the cecum (9). Histology typically resembles that of colitis induced by toxin-producing bacteria (10).For the majority of patients with AAHC, stool testing reveals K. oxytoca in significant amounts (>10⁶ CFU/ml) (9, 23). This Gram-negative rod is ubiquitous in the environment (e.g., soil and water) but can also be isolated from skin, mucous membranes, and the intestines of humans and animals (19). Human infections with K. oxytoca resemble those with Klebsiella pneumoniae; i.e., respiratory and urinary tracts are commonly affected (e.g., nosocomial pneumonia), in addition to soft tissue and hepatobiliary infections (6). Until recently, K. oxytoca was not considered to be an intestinal pathogen, and its presence in stool has placed the organism as a constituent of the normal gut microflora. For the healthy population, colonization of the intestine with K. oxytoca has been reported for 1.6% to 9% of subjects (1, 4, 10, 23). It is important that K. oxytoca constitutively produces β-lactamases conferring resistance to amino- and carboxypenicillins (13), agents typically given before the onset of AAHC. The association of K. oxytoca with AAHC was previously established by an animal model using a K. oxytoca strain isolated from a patient with AAHC in combination with an antibiotic to induce right-sided hemorrhagic colitis (10).In the 1990s, two independent groups reported that K. oxytoca strains isolated from patients with AAHC produce a cytotoxin, which caused cell death in cultured Hep2, Vero, CHO-K1, and HeLa cell lines as well as in an isolated intestinal-loop model (8, 15-17). In contrast, two laboratory strains of K. oxytoca exhibited no cytotoxicity, indicating that cytotoxin production might be strain specific (16, 17). The cytotoxin was reported to be heat labile, insensitive to proteinase digestion, and of a low molecular mass (8, 16, 17). A detailed analysis of the chemical nature and molecular structure of the cytotoxin is not yet available. Moreover, a causal link between toxin production in K. oxytoca and AAHC has not been established.The aim of the current study was to assess whether cytotoxin production is specific to certain subtypes of K. oxytoca and to test the hypothesis that AAHC uniquely correlates with those strains. A total of 121 Klebsiella isolates were investigated, including K. oxytoca strains isolated from stool samples from patients with AAHC, healthy carriers, and patients with colitis/diarrhea of other causes. K. oxytoca strains from infections involving other body sites and other Klebsiella spp. were analyzed in comparison. The characterization of all isolates was performed by using genotypic and biochemical methods, and the capacity of each isolate to induce cytotoxic effects on cultured eukaryotic cells was measured. A subset of strains was genotyped by macrorestriction profiling to assess their genetic relatedness.     

Identification and Determination of Antibiotic Susceptibilities of Brucella Strains Isolated from Patients in Van,Turkey by Conventional and Molecular Methods

Purpose: Brucellosis is a worldwide zoonotic disease and still constitutes a major public health problem. In this study, we aimed to identify biovars of Brucella strains isolated from clinical specimens taken from brucellosis patients from the Eastern Anatolia region as well determine the susceptibility of these isolates to tigecycline and azithromycin, drugs that may serve as alternatives to the conventional drugs used in the therapy.Materials and methods: Seventy-five Brucella spp. isolates were included in the study. All strains were identified by both conventional and molecular methods. Brucella Multiplex PCR kit (FC-Biotech, Code: 0301, Turkey) and B. melitensis biovar typing PCR kit (FC-Biotech, Code: 0302, Turkey) were used for molecular typing. Antimicrobial susceptibilities of all strains were determined by E-tests.Results: By conventional biotyping, 73 strains were identified as B. melitensis biovar 3 and two strains as B. abortus biovar 3. Molecular typing results were compatible with conventional methods. The MIC₅₀ and MIC₉₀ values of doxycycline were 0.047 and 0.094; tigecycline 0.094 and 0.125; trimethoprim/sulfamethoxazole 0.064 and 0.19; ciprofloxacin 0.19 for both; streptomycin 0.75 and 1; rifampin 1 and 2 and azithromycin 4 and 8. According to the MIC values, doxycycline was found to be the most effective antibiotic, followed by tigecycline, trimethoprim-sulfamethoxazole and ciprofloxacin.Conclusion: Currently recommended antibiotics for the treatment of brucellosis such as doxycycline, rifampin, streptomycin, trimethoprim-sulfamethoxazole and ciprofloxacin were found to be still effective. While our results showed that tigecycline can be used an alternative agent in the treatment of brucellosis, azithromycin has not been confirmed as an appropriate agent for the treatment.     

Variable-Number Tandem Repeat Analysis and Multilocus Sequence Typing Data Confirm the Epidemiological Changes Observed with Staphylococcus aureus Strains Isolated from Bloodstream Infections

Since 2000, our geographical region in France systematically surveys bloodstream infections (BSI) due to Staphylococcus aureus. This survey involves 39 health care institutions (HCIs) encompassing 6,888 short-stay beds and was performed during two 3-month periods during 2007 and 2008. The study periods of this survey identified 292 S. aureus isolates causing BSI. Extensive molecular characterization, including genotyping as well as toxin, agr, and staphylococcal cassette chromosome content determinations, allowed us to describe epidemiological evolution in comparison to that discussed in our previous study. Our main epidemiological observation shows that the incidence of BSI remained constant but that methicillin (meticillin)-resistant S. aureus strains with a wider variety of genetic backgrounds now harbor pyl, as has already been reported in different European countries. We noticed stable numbers of BSI episodes involving community-acquired methicillin-sensitive S. aureus (MSSA), whereas a drastic increase in the number of strains harboring the tst gene was recorded. The increase in the number of tst gene-harboring strains is related to known hospital-acquired MSSA isolates and appears related to epidemic episodes in specific HCIs. Monitoring the increase in prevalence of specific strains helps us understand where the standard precautions are not satisfactorily applied or do not efficiently prevent the spread of epidemic MSSA strains in these HCIs. The recent increases in incidence of these strains call for particular vigilance to avoid the spread of potentially virulent MSSA strains harboring the tst gene and for continuance of this strategy of BSI surveillance.Reporting of methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSI) is often mandatory, and reduction of BSI rates is a performance target (2, 15, 16, 19, 22, 23). Since 2000, a prospective, longitudinal survey of BSI has been under way at a regional level in France. Results obtained during the first 7 years of surveillance have been reported (26, 27). After sustained and decreasing incidence rates of S. aureus BSI attributed to successful infection control efforts in participating health care institutions (HCIs), we reported in 2006 a sudden increase in incidence that involved two populations of S. aureus strains: one of methicillin-sensitive S. aureus (MSSA) strains and one of MRSA isolates.First, an increasing incidence of BSI was observed due to MSSA strains, including (i) strains associated with epidemic phenomena in HCIs and (ii) a genetically homogeneous population of tst-positive MSSA isolates, mostly associated with community-acquired (CA) BSI, suggesting clonal spread at a regional level.Second, we observed the emergence of BSI associated with genetically diverse nonmultiresistant staphylococcal cassette chromosome mec type IV (SCCmec IV) MRSA strains (named NORSA) that could not be related to any local outbreak in the participating HCIs.We report here data collected in 2007 and 2008 using exactly the same study design. Again, a large S. aureus population genetic study, including MSSA and MRSA isolates in parallel, was conducted. Strain characterization included antimicrobial susceptibility profiles; luk, tst, eta, and etb gene detection; and SCCmec and pulsed-field gel electrophoresis (PFGE) typing. In addition, and to better understand how populations evolved and interacted, characterization of the S. aureus strains was completed by accessory global regulator (agr) typing and multiple-locus variable-number tandem-repeat analysis (MLVA) and multilocus sequence typing (MLST) analysis.     

Infections in Live Donor Liver Transplant Recipients: A Study of Timeline,Aetiology and Antimicrobial Resistance of Bacterial and Fungal Infections from the Developing World

Infections are the leading cause of morbidity and mortality in liver transplant (LT) recipients. We studied timeline, spectrum of infection, system involved, and antimicrobial resistance in 64 patients undergoing live donor LT with 6-month follow-up. Of 64 patients, 38 (59.5%) patients had 103 infectious episodes, 10 patients had single infectious episode and 28 patients had two or more infectious episodes. 96 (93.2%) were bacterial and Candida infections were in 7 (6.8%). Early phase had 30 (29.1%) episodes; intermediate phase 25 (24.2%) and late phase 48 (46.6%). Mortality was 11/64 (17.1%). Knowledge of timeline, aetiological agent and antimicrobial resistance is useful to guide empirical therapy and infection prevention.     

Antibiotic Susceptibilities of Group C and Group G Streptococci Isolated from Patients with Invasive Infections: Evidence of Vancomycin Tolerance among Group G Serotypes

A retrospective review of medical records for 32 patients with invasive group C streptococcus (GCS) or group G streptococcus (GGS) infections was performed. MICs and minimum bactericidal concentrations (MBCs) of penicillin, erythromycin, and vancomycin for all isolates were obtained. Tolerance of vancomycin, defined as an MBC 32 or more times higher than the MIC, was exhibited by 18 GGS isolates (54%). The identification of tolerance in clinical isolates of GGS and GCS may have clinical implications in treating these seriously ill patients.