石家庄地区儿童急性中耳炎病原菌临床分布特征和主要病原菌耐药性分析

［摘要］ 目的分析石家庄地区儿童急性中耳炎主要病原菌分布及药物敏感性,为临床抗感染治疗提供依据。 方法分析291例急性中耳炎患儿临床资料,收集中耳分泌物进行培养,应用梅里埃VITEK MS质谱仪鉴定菌株,用梅里埃VITEK2 Compact 、BD Phoenix 100并结合K-B法检测药物敏感性。 结果耳脓性分泌物标本共291例,检出细菌211例,阳性率72.5%。其中革兰阳性菌株157株,检出率54.0%,占总阳性的74.4%;最常见的是肺炎链球菌68株,检出率为23.4%,占总阳性的32.2%;其次是金黄色葡萄球菌62株,检出率为21.3%,占总阳性的29.4%。检出革兰阴性杆菌42株,检出率14.4%,占总阳性的19.9%;最常见的是流感嗜血杆菌28株,检出率为9.6%,占总阳性菌株的13.3%。患儿在0~1岁、＞1~3岁、＞3~6岁、＞6岁4个年龄段的病原菌阳性检出率差异有统计学意义（P＜0.05）,在0~1岁阳性检出率最高,在＞3~6岁阳性检出率最低。按发生时间,患儿在各个季度检出率差异有统计学意义（P＜0.05）,第四季度检出率最高,第二季度检出率最低。耳分泌物来源的肺炎链球菌68株,对万古霉素、利奈唑胺均完全敏感,对红霉素完全耐药。耳分泌物来源的金黄色葡萄球菌62株,对左氧氟沙星、利福平、庆大霉素、莫西沙星、万古霉素和利奈唑胺均完全敏感,对红霉素、克林霉素和青霉素均完全耐药;耐甲氧西林金黄色葡萄球菌（Methicillin-resistant staphylococcus aureus,MRSA）34例,占金黄色葡萄球菌的54.8%。流感嗜血杆菌检出28株,对头孢他啶、头孢吡肟、美罗培南、亚胺培南、氨曲南和环丙沙星均完全敏感,对复方新诺明耐药性最高。 结论石家庄地区儿童急性中耳炎的主要致病菌为肺炎链球菌、金黄色葡萄球菌和流感嗜血杆菌,临床常用的多种药物对其敏感性较高,临床可根据细菌培养及药敏试验结果选取合理的抗菌药物。     

Clostridium difficile

Clostridium difficile is the leading cause of healthcare‐associated infectious diarrhea. Although C difficile is part of normal flora in some healthy individuals, patients with selective risk factors are often vulnerable to the toxigenic potential of this virulent healthcare pathogen. The spectrum of C difficile infection (CDI) is highly variable, ranging from mild to severe illness, presenting with single to multiple disease recurrences. Current approaches to treatment are based on severity of illness, number of recurrences, and clinical presentation. Oral vancomycin and metronidazole have formed the foundation for treatment of CDI, but therapeutic failures are commonly reported, especially involving hypervirulent clones. Alternative therapies, including newer antimicrobials, probiotics, immunotherapy, and fecal transplantation, have all met with varying degrees of efficacy. Although toxigenic culture (TC) testing from anaerobic culture remains the gold standard, newer technologies, including enzyme immunoassay, common antigen (glutamate dehydrogenase) testing, and real‐time polymerase chain reaction (PCR) are less time‐consuming and rapid. However, TC and PCR have reported high specificity and sensitivity when compared with other laboratory tests. Because of the significant morbidity and mortality associated with CDI, a high index of suspicion is warranted. Prevention and eradication of CDI require a multidisciplinary approach, including early disease recognition through appropriate surveillance, implementation of effective contact isolation strategies, adherence to environmental controls, judicious hand hygiene, evidence‐based treatment, and management that includes antibiotic stewardship, continuous education of healthcare workers, and administrative support.     

Peptide vaccination is superior to genetic vaccination using a recombineered bacteriophage λ subunit vaccine

Genetic immunization holds promise as a vaccination method, but has so far proven ineffective in large primate and human trials. Herein, we examined the relative merits of genetic immunization and peptide immunization using bacteriophage λ. Bacteriophage λ has proven effective in immune challenge models using both immunization methods, but there has never been a direct comparison of efficacy and of the quality of immune response. In the current study, this vector was produced using a combination of cis and trans phage display. When antibody titers were measured from immunized animals together with IL-2, IL-4 and IFNγ production from splenocytes in vitro, we found that proteins displayed on λ were superior at eliciting an immune response in comparison to genetic immunization with λ. We also found that the antibodies produced in response to immunization with λ displayed proteins bound more epitopes than those produced in response to genetic immunization. Finally, the general immune response to λ inoculation, whether peptide or genetic, was dominated by a Th1 response, as determined by IFNγ and IL-4 concentration, or by a higher concentration of IgG2a antibodies.     

Alkyl hydroperoxide reductase: a candidate Helicobacter pylori vaccine

Helicobacter pylori (H. pylori) is the most important etiological agent of chronic active gastritis, peptic ulcer disease and gastric cancer. The aim of this study was to evaluate the efficacy of alkyl hydroperoxide reductase (AhpC) and mannosylated AhpC (mAhpC) as candidate vaccines in the C57BL/6J mouse model of H. pylori infection. Recombinant AhpC was cloned, over-expressed and purified in an unmodified form and was also engineered to incorporate N and C-terminal mannose residues when expressed in the yeast Pichia pastoris. Mice were immunized systemically and mucosally with AhpC and systemically with mAhpC prior to challenge with H. pylori. Serum IgG responses to AhpC were determined and quantitative culture was used to determine the efficacy of vaccination strategies. Systemic prophylactic immunization with AhpC/alum and mAhpC/alum conferred protection against infection in 55% and 77.3% of mice, respectively. Mucosal immunization with AhpC/cholera toxin did not protect against infection and elicited low levels of serum IgG in comparison with systemic immunization. These data support the use of AhpC as a potential vaccine candidate against H. pylori infection.     

Transmission of Bordetella holmesii during pertussis outbreak, Japan

We describe the epidemiology of a pertussis outbreak in Japan in 2010-2011 and Bordetella holmesii transmission. Six patients were infected; 4 patients were students and a teacher at the same junior high school. Epidemiologic links were found between 5 patients. B. holmesii may have been transmitted from person to person.     

晚期肺癌合并慢阻肺化疗后肺部感染的病原谱及耐药性分析

目的探讨合并慢性阻塞性肺疾病(简称慢阻肺)的晚期肺癌患者化疗后肺部感染的病原菌分布及其耐药情况,指导临床合理用药。方法选择2011年1月至2014年5月徐州医学院附属医院呼吸科收治的65例化疗后肺部感染的晚期肺癌合并慢阻肺患者为研究对象,对所有患者痰标本中分离出的病原菌进行菌种鉴定和耐药性分析。结果共分离出103株病原菌,其中革兰阴性杆菌79株,占76.6%;革兰阳球性菌8株,占7.8%;真菌16株,占15.6%。最主要的革兰阴性杆菌依次为大肠埃希氏菌(28.2%)、铜绿假单胞菌(15.5%)、肺炎克雷伯菌(13.6%)、鲍曼不动杆菌(8.7%)、阴沟肠杆菌(5.8%)。大肠埃希氏菌、肺炎克雷伯杆菌和铜绿假单胞菌对对亚胺培南、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦、阿米卡星敏感性较高。鲍曼不动杆菌对碳青霉烯类药物耐药率高(55.6%),对头孢哌酮舒巴坦和哌拉西林他唑巴坦敏感性相对较好。金黄色葡萄球菌未发现对万古霉素耐药。结论合并慢阻肺的晚期肺癌化疗后肺部感染致病菌以革兰阴性杆菌为主;其次为真菌、革兰氏阳性球菌。细菌耐药情况较为严重,应结合本地区病原菌分布特点及耐药状况,合理选用抗菌药物。     

细菌性脑膜炎病原菌分布和耐药性变迁

目的了解细菌性脑膜炎致病菌的分布特点以及耐药谱的变化。方法对1996—2004年川北医学院附属医院收治的细菌性脑膜炎病例进行脑脊液和血培养，并对致病菌进行药敏试验。结果从316例患者的276份脑脊液和269份血标本中共分离出62株致病菌。葡萄球菌最多占30．6％（19／62），其次为大肠埃希菌占14．5％（9／62）、脑膜炎奈瑟菌占11．3％（7／62）和B组链球菌占9．7％（6／62）。葡萄球菌对青霉素的耐药率高于83．3％，对苯唑西林、头孢唑啉的耐药也逐渐升高。肠杆菌科细菌对氨苄西林的耐药率高达87．5％以上，且对第三代头孢菌素、左氧氟沙星的耐药呈逐年增高趋势。结论葡萄球菌、肠杆菌科细菌、脑膜炎奈瑟菌是主要致病菌。细菌耐药性普遍增加。