Novel Corynebacterium diphtheriae in Domestic Cats

Novel nontoxigenic Corynebacterium diphtheriae was isolated from a domestic cat with severe otitis. Contact investigation and carrier study of human and animal contacts yielded 3 additional, identical isolates from cats, although no evidence of zoonotic transmission was identified. Molecular methods distinguished the feline isolates from known C. diphtheriae.     

Toxigenic Corynebacterium diphtheriae Infection in Cat,Texas, USA

We report a toxigenic strain of Corynebacterium diphtheriae isolated from an oozing dermal wound in a pet cat in Texas, USA. We also describe the epidemiologic public health efforts conducted to identify potential sources of infection and mitigate its spread and the molecular and genetic studies performed to identify the bacterium.     

Antibacterial cleaning products and drug resistance

We examined whether household use of antibacterial cleaning and hygiene products is an emerging risk factor for carriage of antimicrobial drug-resistant bacteria on hands of household members. Households (N = 224) were randomized to use of antibacterial or nonantibacterial cleaning and hygiene products for 1 year. Logistic regression was used to assess the influence of antibacterial product use in homes. Antibacterial product use did not lead to a significant increase in antimicrobial drug resistance after 1 year (odds ratio 1.33, 95% confidence interval 0.74-2.41), nor did it have an effect on bacterial susceptibility to triclosan. However, more extensive and longer term use of triclosan might provide a suitable environment for emergence of resistant species. Further research on this issue is needed.     

Antimicrobial drug resistance in Escherichia coli from humans and food animals, United States, 1950-2002

We conducted a retrospective study of Escherichia coli isolates recovered from human and food animal samples during 1950-2002 to assess historical changes in antimicrobial drug resistance. A total of 1,729 E. coli isolates (983 from humans, 323 from cattle, 138 from chickens, and 285 from pigs) were tested for susceptibility to 15 antimicrobial drugs. A significant upward trend in resistance was observed for ampicillin (p<0.001), sulfonamide (p<0.001), and tetracycline (p<0.001). Animal strains showed increased resistance to 11/15 antimicrobial agents, including ampicillin (p<0.001), sulfonamide (p<0.01), and gentamicin (p<0.001). Multidrug resistance (≥3 antimicrobial drug classes) in E. coli increased from 7.2% during the 1950s to 63.6% during the 2000s. The most frequent co-resistant phenotype observed was to tetracycline and streptomycin (29.7%), followed by tetracycline and sulfonamide (29.0%). These data describe the evolution of resistance after introduction of new antimicrobial agents into clinical medicine and help explain the range of resistance in modern E. coli isolates.     

Widespread Disease in Hedgehogs (Erinaceus europaeus) Caused by Toxigenic Corynebacterium ulcerans

Toxin-producing Corynebacterium ulcerans, a causative agent of diphtheria in humans, was isolated from 53 hedgehogs in Belgium during the spring of 2020. Isolates showed low levels of acquired antimicrobial drug resistance. Strain diversity suggests emergence from an endemic situation. These findings stress the need for raising public awareness and improved wildlife disease surveillance.     

金昌市5所医院2005年临床分离菌耐药性分析

目的调查金昌市5所二级以上医院临床标本分离菌的菌种分布及其对常用抗菌药物的耐药状况。方法收集上述医院2005年临床标本分离的细菌,采用K-B琼脂扩散法进行药敏试验,按美国临床实验室标准化委员会2005版标准判定结果;采用WHONET5.0软件对数据进行统计分析。结果共分离546株菌,其中革兰阴性(G-)菌365株(66.85%),革兰阳性(G )球菌181株(33.15%)。G-杆菌分离率最高的为大肠埃希菌16.67%,其中大肠埃希菌和肺炎克雷伯菌产超广谱β-内酰胺酶(ESBLs)菌分别占18.68%和15.38%;分离率最高的G 球菌为金黄色葡萄球菌(15.20%)和凝固酶阴性葡萄球菌(9.89%),未分离出耐万古霉素金黄色葡萄球菌。大肠埃希菌对氟喹诺酮类药物和庆大霉素的耐药率接近或>50%;阴沟肠杆菌和弗劳地枸橼酸杆菌对第一代头孢菌素的耐药率接近或达到80%;铜绿假单胞菌对亚胺培南的耐药率达19.73%;鲍曼不动杆菌对亚胺培南的耐药率达11.87%。结论临床标本分离菌耐药现象十分普遍,多重耐药性日趋严重。加强细菌学检验,及时了解其耐药性变迁对指导临床合理用药,有效控制感染具有重要意义。     

临床分离大肠埃希菌耐药性分析及I型整合子研究

目的了解临床分离大肠埃希菌对常用抗菌药物的耐药状况;研究整合子在大肠埃希菌中的分布情况,探讨其与大肠埃希菌耐药性之间的相关性。方法收集广东省3所医院2010-2012年分离的大肠埃希菌,采用K B纸片扩散法进行药敏试验;聚合酶链反应（PCR）法扩增3类整合子整合酶基因和整合子可变区,测序分析整合子所携带的耐药基因盒类型。结果共收集156株大肠埃希菌,其对青霉素类、头孢菌素类、氟喹诺酮类、氨基糖苷类和磺胺类等的大多数抗菌药物的耐药率＞50%;耐药率＜10%的抗菌药物有头孢哌酮/舒巴坦（0）、亚胺培南（3.85%）、头孢替坦（4.35%）、厄他培南（7.69%）和哌拉西林/他唑巴坦（8.97%）;I类整合子的检出率为57.69%（90/156）,多重耐药菌与非多重耐药菌的整合子检出率分别为66.00%（66/100）和64.71%（22/34）,两组比较,差异无统计学意义（P＞0.05）,但分别与敏感菌组（9.09%,2/22）相比,差异均有统计学意义（P＜0.01）。所检出的整合子可变区分为9种类型,大部分都含有aadA和dfrA耐药基因盒。结论大肠埃希菌整体耐药情况严重;I类整合子在临床分离大肠埃希菌中分布广泛,并与大肠埃希菌的耐药性关系密切,主要介导对氨基糖苷类、磺胺类、β 内酰胺类等多种抗菌药物的耐药性。     

细胞壁缺陷对白喉棒状杆菌Tox基因影响

目的探讨细胞壁缺陷对白喉棒状杆菌毒力基因及其表达的影响。方法以非高渗分离培养法诱导并获得产毒性白喉棒状杆菌稳定L型纯培养物，提取白喉棒状杆菌稳定L型的染色体DNA，用Tox基因特异性引物进行PCR扩增，并进行序列测定和分析。分别采用对流免疫电泳（CIEP）和十二烷基磺酸钠-不连续聚丙烯酰胺凝胶电泳（SDS-PAGE）检测白喉棒状杆菌稳定L型可溶性代谢产物中的白喉毒素蛋白质。结果白喉棒状杆菌在氨苄青霉素作用下可发生细胞壁缺陷而成为L型，该稳定L型的传代培养物可仍然保留同其亲代细菌型一致的Tox基因及其核苷酸序列；但在其可溶性代谢产物中并未检测到白喉毒素蛋白质。结论白喉棒状杆菌稳定L型虽然保留了Tox基因但并不能表达白喉毒素蛋白质，提示细胞壁缺陷可影响Tox基因在宿主菌细胞内的表达。     

Antimicrobial drug use and resistance in Europe

Our study confronts the use of antimicrobial agents in ambulatory care with the resistance trends of 2 major pathogens, Streptococcus pneumoniae and Escherichia coli, in 21 European countries in 2000-2005 and explores whether the notion that antimicrobial drug use determines resistance can be supported by surveillance data at national aggregation levels. The data obtained from the European Surveillance of Antimicrobial Consumption and the European Antimicrobial Resistance Surveillance System suggest that variation of consumption coincides with the occurrence of resistance at the country level. Linear regression analysis showed that the association between antimicrobial drug use and resistance was specific and robust for 2 of 3 compound pathogen combinations, stable over time, but not sensitive enough to explain all of the observed variations. Ecologic studies based on routine surveillance data indicate a relation between use and resistance and support interventions designed to reduce antimicrobial drug consumption at a national level in Europe.     

Antimicrobial drug resistance in Singapore hospitals

A new national antimicrobial resistance surveillance program in Singapore public hospitals that uses WHONET detected high levels of methicillin resistance among Staphylococcus aureus (35.3%), carbapenem resistance among Acinetobacter spp. (49.6%), and third-generation cephalosporin resistance among Klebsiella pneumoniae (35.9%) hospital isolates in 2006. Antimicrobial drug resistance is a major problem in Singapore.     

Antimicrobial drug resistance of Salmonella isolates from meat and humans, Denmark

We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from humans showed resistance rates lower than those found in imported meat but higher than in domestic meat. These findings indicate that programs for controlling resistant Salmonella spp. are a global issue.     

耐碳青霉烯类肺炎克雷伯菌的药敏结果及耐药基因

目的分析某院耐碳青霉烯类肺炎克雷伯菌(CRKP)的药物敏感性及耐药基因携带情况。方法收集2017年1月—2018年6月该院临床分离的CRKP,对菌株进行药物敏感性分析,应用聚合酶链式反应(PCR)检测耐药基因携带情况。结果共收集57株CRKP,主要来源于呼吸道标本,其中痰34株,肺泡灌洗液11株;来源科室主要为神经内科(20株,35.09%)、呼吸内科(15株,26.32%)、重症医学科(9株,15.79%)。CRKP对大部分抗菌药物耐药,部分抗菌药物耐药率相对较低,其中复方磺胺甲口恶唑耐药率最低(15.79%),其次为替加环素(50.88%)、阿米卡星(57.89%)。共检出2种碳青霉烯酶基因(KPC-2、NDM-1),4种超广谱β-内酰胺酶(ESBLs)基因(SHV、CTX-M-9、TEM、CTX-M-1)。57株CRKP均检出ESBLs基因,其中39株(68.42%)检出KPC-2基因,仅有1株检出NDM-1基因。结论临床分离的CRKP耐药形势严峻,并且携带多种耐药基因,其中最常见的产碳青霉烯酶为KPC。