九项呼吸道病原体检测在小儿呼吸道感染中的诊断价值

目的探讨呼吸道病原体九联检在小儿呼吸道感染中的临床应用价值。方法对2012年3月—2013年4月期间在该院住院的呼吸道感染的患儿(共104例)采用九项呼吸道感染病原体Ig M抗体检测试剂(间接免疫荧光法)同时检测九项病原体的Ig M抗体。结果在小儿呼吸道感染患者中,九种病原体检出的阳性率为57.69%,其中主要以肺炎支原体最为常见,占阳性例数的56.7%,其次为腺病毒40%、嗜肺军团菌23.3%;混合感染占感染比例的33.3%。结论呼吸道病原体九联检在小儿呼吸道感染检测中检出阳性率高,检测的病原体种类多,发现病原体时间早,对临床的及时诊断、治疗及用药有十分重要的意义。     

Salmonella enteritidis diarrhoea in Harare, Zimbabwe

The study was conducted to determine the prevalence of Salmonella enteritidis diarrhoea in an urban area in Zimbabwe. Stool specimens from people of all ages presenting at primary level health centres in Harare were investigated for S. enteritidis and other bacterial and parasitic enteric pathogens. The first 46 S. enteritidis isolates were phage-typed, and all isolates were tested for susceptibility to ampicillin (10 microg), chloramphenicol (30 microg), cotrimoxazole (25 microg), tetracycline (30 microg), gentamicin (10 microg), nalidixic acid (30 microg), ciprofloxacin (5 microg) and ceftriaxone (30 microg). S. enteritidis was isolated in 74 (1.8%) of 4155 stool specimens which represented 30.7% of all Salmonella species isolated. The most common S. enteritidis phage type was 4 (78.3%) followed by 7, 9 and 23 (8.7%, 2.2%, 2.2%, respectively) All S. enteritidis isolates were sensitive to gentamicin, ciprofloxacin and ceftriaxone. Less than 10% of the isolates were resistant to the other antimicrobials except ampicillin, to which 13.5% were resistant. One isolate was resistant to ampicillin, chloramphenicol, cotrimoxazole and nalidixic acid.     

Mechanisms of antimicrobial resistance among hospital-associated pathogens

Introduction: The introduction of antibiotics revolutionized medicine in the 20th-century permitting the treatment of once incurable infections. Widespread use of antibiotics, however, has led to the development of resistant organisms, particularly in the healthcare setting. Today, the clinician is often faced with pathogens carrying a cadre of resistance determinants that severely limit therapeutic options. The genetic plasticity of microbes allows them to adapt to stressors via genetic mutations, acquisition or sharing of genetic material and modulation of genetic expression leading to resistance to virtually any antimicrobial used in clinical practice.

Areas covered: This is a comprehensive review that outlines major mechanisms of resistance in the most common hospital-associated pathogens including bacteria and fungi.

Expert commentary: Understanding the genetic and biochemical mechanisms of such antimicrobial adaptation is crucial to tackling the rapid spread of resistance, can expose unconventional therapeutic targets to combat multidrug resistant pathogens and lead to more accurate prediction of antimicrobial susceptibility using rapid molecular diagnostics. Clinicians making treatment decisions based on the molecular basis of resistance may design therapeutic strategies that include de-escalation of broad spectrum antimicrobial usage, more focused therapies or combination therapies. These strategies are likely to improve patient outcomes and decrease the risk of resistance in hospital settings.     

广州市越秀区食源性非伤寒沙门菌感染的病例对照研究

目的 探索广州市越秀区食源性非伤寒沙门菌感染的流行病学危险因素,为制定相应的预防控制措施提供依据.方法 运用病例对照研究方法,收集2012～2014年广州市越秀区确诊感染食源性非伤寒沙门菌的病例,以1:1比例选择年龄段、性别及所在的居住地匹配者为对照组进行面对面问卷调查,将所得数据用配对t检验或卡方分析,用OR值比较相关危险因素.结果 从调查中发现在发病前5d有将禽蛋和禽肉储于冰箱(P=0.03,OR=2.67),不常洗手(P＜0.01,OR=29.40),不彻底清洗菜板(P＜0.01,OR=25.72)等习惯,在发病前5d曾进食过含禽蛋饭菜(P＜0.01,OR=4.68),是主要的危险因素.结论 食源性非伤寒沙门菌感染的主要危险因素是不良卫生习惯和饮食习惯,改变不良生活习惯,从源头上切断非伤寒沙门菌污染是防控工作的重要方向.     

Novel Approaches to Improve the Intrinsic Microbiological Safety of Powdered Infant Milk Formula

Human milk is recognised as the best form of nutrition for infants. However; in instances where breast-feeding is not possible, unsuitable or inadequate, infant milk formulae are used as breast milk substitutes. These formulae are designed to provide infants with optimum nutrition for normal growth and development and are available in either powdered or liquid forms. Powdered infant formula is widely used for convenience and economic reasons. However; current manufacturing processes are not capable of producing a sterile powdered infant formula. Due to their immature immune systems and permeable gastro-intestinal tracts, infants can be more susceptible to infection via foodborne pathogenic bacteria than other age-groups. Consumption of powdered infant formula contaminated by pathogenic microbes can be a cause of serious illness. In this review paper, we discuss the current manufacturing practices present in the infant formula industry, the pathogens of greatest concern, Cronobacter and Salmonella and methods of improving the intrinsic safety of powdered infant formula via the addition of antimicrobials such as: bioactive peptides; organic acids; probiotics and prebiotics.     

Microbiota That Affect Risk for Shigellosis in Children in Low-Income Countries

Pathogens in the gastrointestinal tract exist within a vast population of microbes. We examined associations between pathogens and composition of gut microbiota as they relate to Shigella spp./enteroinvasive Escherichia coli infection. We analyzed 3,035 stool specimens (1,735 nondiarrheal and 1,300 moderate-to-severe diarrheal) from the Global Enteric Multicenter Study for 9 enteropathogens. Diarrheal specimens had a higher number of enteropathogens (diarrheal mean 1.4, nondiarrheal mean 0.95; p<0.0001). Rotavirus showed a negative association with Shigella spp. in cases of diarrhea (odds ratio 0.31, 95% CI 0.17–0.55) and had a large combined effect on moderate-to-severe diarrhea (odds ratio 29, 95% CI 3.8–220). In 4 Lactobacillus taxa identified by 16S rRNA gene sequencing, the association between pathogen and disease was decreased, which is consistent with the possibility that Lactobacillus spp. are protective against Shigella spp.–induced diarrhea. Bacterial diversity of gut microbiota was associated with diarrhea status, not high levels of the Shigella spp. ipaH gene.     

不同方法对食源性致病菌耐药性监测研究

目的了解江苏地区食源性致病菌的常用抗菌药耐药谱,评价不同药敏方法在致病菌耐药性监测中的适用性。方法用Etest和微量肉汤稀释法,对江苏省2012-2014年食源性疾病常规监测检出的金黄色葡萄球菌、副溶血性弧菌、沙门菌菌株进行药敏鉴定。结果金黄色葡萄球菌对红霉素的耐药率最高,其次为复方磺胺甲噁唑和四环素,且有多重耐药;副溶血性弧菌除对四环素和复方磺胺甲噁唑有一定的耐药,对其他6种革兰氏阴性菌抗生素均敏感。沙门菌对萘啶酸的耐药率超过50.0%。两种方法药敏检测结果对不同抗生素符合率有差异,但符合率均80%。结论 Etest和微量肉汤稀释法有较好的一致性,但所需时间及操作要求有差异,可根据实际需要进行选择。     

济南市平阴县农村环境鼠形动物调查与携带病原体检测

目的 了解平阴县农村环境鼠形动物种类分布及携带病原体情况。方法 采用鼠夹和粘鼠板捕获动物,解剖取其内脏组织,利用荧光定量PCR法检测8种致病病原体核酸。结果 共捕获100只鼠形动物,包括小家鼠、褐家鼠和鼩鼱,所占比例分别为55%、40%和5%;平均捕鼠率为1.81%,鼠夹法和粘鼠板法捕鼠率分别为0.69%和3.32%,差异有统计学意义(χ²=52.20, P<0.001);莫氏立克次体和致病性钩端螺旋体的检出率最高,均为17.00%,嗜吞噬细胞无形体、恙虫病东方体、土拉弗朗西斯菌和巴尔通体的检出率为1.00%~5.00%,并未检出汉坦病毒和发热伴血小板减少综合征布尼亚病毒;共检出混合感染6只,混合感染率为15.00%,均为双重感染。结论 平阴县农村人居环境中鼠形动物以小家鼠和褐家鼠为主,存在莫氏立克次体、致病性钩端螺旋体、嗜吞噬细胞无形体、恙虫病东方体、土拉弗朗西斯菌和巴尔通体的单一感染及混合感染,应加强当地人群感染和相关疾病的监测。     

新发再发病原体与血液安全

乙肝病毒、丙肝病毒及人类免疫缺陷病毒等输血相关病原体经输血传播风险逐渐减低,目前维持在较低水平,新发再发病原体越来越多被认识到其对输血安全构成威胁,其中一些已知的,如疟原虫、人细小病毒B19、戊型肝炎病毒、登革热病毒、人类T淋巴细胞白血病病毒及西尼罗病毒等已经被证实可经输血传播。其中,登革病毒曾经在中国爆发或流行过,将来或可再次爆发流行,其对血液安全威胁不容忽视。目前,我国常规血液筛查的病原体筛查项目只有4种,由于新发再发病原体层出不穷,采供血系统尚未建立相应的筛查制度,我国的血液筛查系统面临很大的挑战。我们讨论了几种新发再发病原体在我国的流行情况,探讨其对血液安全的影响以及采供血机构个性化病原体筛查策略制订的可行性。     

新型冠状病毒和其他病原体核酸检测结果分析及其评价

目的:通过核酸检测新型冠状病毒,探讨PCR检测方法在新型冠状病毒和其他病原体感染的临床应用。方法:收集1例确诊患者送检的咽拭子样本,通过柱提法提取病毒RNA,使用商品化的扩增试剂和传统PCR技术进行检测。结果:A、B、C、D、E、F、G新冠检测试剂盒的结果均为阳性,PCR也能扩增出特异性条带,此外还检测出该患者有EB病毒和腺病毒病原体感染的情况。结论:7种扩增试剂盒检出阳性样本结果基本一致,均可用于实验室检测,该样本检测出新冠病毒的同时还检测出其他呼吸道相关病原体,为新冠肺炎的鉴别、诊断、治疗提供依据。