WCG空肠/结肠弯曲菌无血培养基的研究

本研究的WCG无血培养基与Camp-BAP含血培养基同时进行对已知空肠/结肠弯曲菌的培养计数及599份来自鸡和人类粪便标本中空肠/结肠弯曲菌的分离培养试验,结果表明13株已知空肠/结肠弯曲菌在WCG培养基上生长的菌落数(CFU/ml)、菌落形态、菌体特征和生化特性及5次共599份来自鸡和人类粪便标本分离培养取得与Camp-BAP培养基一致或较优的效果。为此,我们认为WCG无血培养基可代替Camp-BAP含血培养基用作培养分离空肠/结肠弯曲菌。     

用无血培养基分离空肠弯曲菌的效果研究

空肠弯曲菌是引起急性腹泻的重要病原菌之一。我们于1986年11月至1987年5月应用无血培养基与改良Camp-BAP含血培养基(简称含血培养基)进行已知空肠弯曲菌株及鸡、人肛拭标本在两种培养基上的检出阳性率、染色形态、菌落特征、菌量分布、抑制杂菌等方面的效果研究,取得了满意结果,现报告如下。     

一种新的空肠弯曲菌培养基的研究

空肠弯曲菌(空弯菌)在FBPCA和Skirrow培养基上,经42℃24和48小时及37和42℃48小时培养,FBPCA上的菌落数接近,均高于Skirrow培养基。100份鸡粪标本42℃24与48小时的检出率,FBPCA无显著性差异(P>0.05),但均显著地高于Skirrow培养基(P<0.005,P<0.05)。 结果提示FBPCA优于Skirrow培养基,可在42℃24小时及37℃48小时分离空弯菌,空弯菌生长较快,菌落大,数量多,且制备简易、价廉。     

不同品系养殖鸡弯曲菌感染调查

目的了解规模化养殖鸡弯曲菌感染现状。方法随机采集北京市某规模化养殖场蛋鸡(养殖时间大于120d)和肉鸡(养殖时间小于42d)肛拭子标本,采用两种分离培养方案(80份蛋鸡和200份肉鸡标本直接经选择性培养基划线培养,150份肉鸡标本经24h增菌后采用选择性培养基划线培养)进行弯曲菌的微需氧(5%O2、10%CO2和85%N2)培养。从肉鸡标本中随机选取50份,提取病原菌DNA,进行弯曲菌荧光定量PCR检测,并对相同培养条件下生长菌落进行质谱鉴定。结果 80份蛋鸡标本中分离到24株空肠弯曲菌,阳性率为30%;350份肉鸡标本未检测到弯曲菌。通过质谱菌落鉴定,205份标本检测到奇异变形杆菌,检出率为58.6%;145份标本检测到大肠埃希菌,检出率为41.4%。50份肉鸡粪便标本弯曲菌荧光定量PCR检测结果均为阴性,与分离培养结果一致。结论北京市规模化养殖蛋鸡弯曲菌感染率较高,饲养时间较短的肉鸡未发现弯曲菌感染。     

空肠/结肠弯曲菌在人、鸡和猪中的分布

<正> 自1977年Skirrow应用含抗生素的选择性培养基,简化腹泻患者粪便中弯曲菌的分离培养以来,现已充分确定,嗜热弯曲菌(Themophilic eampylo-bacter)是人类肠炎的常见病原菌,根据马尿酸盐水解试验,可将其分为空肠弯曲菌(C.jejuni)和结肠弯曲菌(C.coli)。国外的调查指出,作为人的腹泻病因,空肠弯曲菌远较结肠弯曲菌多见。近年来,国内已陆续报道,从腹泻病例中分     

贵州省8例空肠弯曲菌病例的病原学诊断与分析

目的 对来自贵州省的8例空肠弯曲菌病疑似病例进行病原学诊断与分子流行病学特征分析,为病例的确诊和贵州省空肠弯曲菌病疫情的预防和控制提供科学依据。方法 对8例疑似病例粪便和血液标本进行细菌分离,采用传统方法和多重PCR方法对空肠弯曲菌可疑菌株进行鉴定,应用脉冲场凝胶电泳分型技术(PFGE)对空场弯曲菌分离株进行分析。结果 8例空肠弯曲菌病疑似病例标本均分离出空肠弯曲菌可疑菌株,PCR扩增出空肠弯曲菌预期大小的目的基因片段,PFGE显示8株菌经SamI酶切后产生7~10条DNA条带,聚类分析显示,8株菌株分为7个PFGE带型,8株菌的相似性>50%,其中GZ201004和GZ201005两株腹泻病例来源分离株相似性为100%,血培养血液标本分离株GZ201201与粪便标本分离株GZ201007相似性为66.7%。结论 8例空肠弯曲菌病疑似病例均检出空肠弯曲菌,PFGE显示GZ201004和GZ201005两株为同一来源,但8例病例来源菌株存在PFGE带型多态性,该研究结果为病例的确诊和疫情的预防和控制提供了科学依据。     

从鸡粪中分离空肠弯曲菌方法的比较试验

作者比较了鸡粪样本运送、保存和培育空肠弯曲菌的方法,从比较试验的结果获知: 1.保存用的基液中粪便内空肠弯曲菌的成功分离,保存运送在常温下的时间可达2～3小时; 2.改变空弯菌选择性含血琼脂培养基的成份(以先锋霉素Ⅰ代替万古霉素,并减少培养基中含羊血量至5％)于微氧环境中成功地从鸡粪中分出空弯菌; 3.以抽、换气法(使含氮84.5％、CO_2 13％及O_2 2.5％)与烛缸内培育法(使成微氧环境)均能使粪样中的弯曲菌都获得了生长,但上述二法中以抽、换气法提供的微氧环境较优。     

市售肉类空肠弯曲菌污染调查

<正> 空肠弯曲菌广泛寄生于动物肠内,家禽、家畜的带苗率很高。为了解禽畜动物在屠宰、加工、销售等过程中的污染情况,作者等对福州、厦门两市部分农贸市场出售的新鲜肉类进行空肠弯曲菌污染调查,现将结果报道如下。 一、材料与方法:在福州、厦门两市农贸市场个体摊点出售的新鲜猪肉、羊肉、鸡肉和鸭肉中,用消毒棉签直接在其表面涂擦取样(鸡、鸭肉以一头为1份)。置Cary-Blair运送培养基,3小时内送实验室接种于Campy-BAP琼脂平板,42℃微氧环境培养48小时。挑取可疑菌落,按常规法进行鉴定。阳性菌分别进行生物学分型和血清学分型及肠毒素检测。生物学分型按Skirrow法,用马尿酸水解和快速H_2S试验     

空肠弯曲菌肠炎

空肠弯曲菌肠炎是由胎儿空肠弯曲菌亚种(简称空肠弯曲菌)引起的。在腹泻患者中,该病约占5～14%。空肠弯曲菌为革兰氏染色阴性菌。1972年Dekeyser等采用过滤与选择性培养基首先从腹泻病人粪便中分离到此菌。1982年国内上海首次报     

贵州省首例空肠弯曲菌菌血症病例病原鉴定和亚种分型

目的 对贵州省1例菌血症患儿血液中分离的疑似空肠弯曲菌进行鉴定。方法 运用传统细菌学方法和分子生物学方法,对从菌血症患者血液分离的可疑空肠弯曲菌进行鉴定和亚种分型。结果 来自菌血症患儿血液的可疑菌株,经传统生化鉴定为空肠弯曲菌空肠亚种,特异性多重PCR方法鉴定为弯曲菌属空肠弯曲菌,NAP-mPCR方法鉴定为空肠弯曲菌空肠亚种。结论 分离自贵州省菌血症患儿血液的菌株确认为空肠弯曲菌空肠亚种,NAP-mPCR方法可将空肠弯曲菌鉴定到亚种水平。     

Chicken carcasses as a source of Campylobacter jejuni in Belo Horizonte, Brazil

The presence of Campylobacter jejuni was investigated in stool specimens from chicken meat workers and in ready-for-market chicken carcasses from one industrial and nine non industrial slaughters in Belo Horizonte. In the latter C. jejuni was isolated from 19 (38.0%) of the 50 chicken carcasses and from 2 (13.3%) of the stool specimens obtained from 15 chicken meat workers. In the industrial slaughter it was found in only 1 (2.0%) of the 50 chicken carcasses and it was not isolated from any of the 40 stool specimens. There was a significant difference between industrial and non industrial slaughter in regard to the frequency of C. jejuni isolation from carcasses (p = 0.000002), probably due to the low hygiene conditions present in non industrial slaughters. The results of antimicrobial susceptibility tests, SDS gel electrophoresis and biotyping of the strains isolated from stool specimens obtained from chicken meat workers were similar to those observed in strains isolated from chicken carcasses which suggest that chicken could be the source of C. jejuni for the workers and both, chicken and workers, could be implicated in the transmission of C. jejuni infection in Belo Horizonte.     

Study on the pathogenicity of Campylobacter jejuni by modifying the medium

Campylobacter jejuni has been documented as one of the major aetiological agents of diarrhoeal illness all over the world. Studies revealed its pathogenicity by different assay methods, but none could be strongly recommended as a tool for differentiating toxigenic strains of C. jejuni. This study was an attempt to demonstrate better its pathogenicity by media modification. Fifteen isolates of C. jejuni recovered from diarrhoeal patients at the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), Dhaka Hospital were included in this study. The standard medium for C. jejuni was modified by the incorporation of FeCl3 at different concentrations. The pathogenicity of the test isolates were studied by rabbit ileal loop assay; Chinese hamster ovary (CHO), human epithelial cervical carcinoma (HeLa); Y-1 adrenal cell lines and suckling mouse assay. Sonicated extracts of the test organisms, grown with FeCl3 supplement, were also assayed. An enhanced growth of C. jejuni was obtained with the increasing concentration of FeCl3 supplementation in the medium. Only five isolates of C. jejuni produced cytotoxic effect on HeLa cell monolayer. Other cell lines were not affected by the test specimens or sonicates. Rabbit ileal loop assay did not reveal any fluid accumulation but on dissection, the test loops were found highly haemorrhagic. No heat-stable (ST) toxin could be detected. Cell-free culture supernatant of patients' isolates of C. jejuni had an effect on HeLa cell monolayer. Sonicated extracts of patients' extracts had a greater effect on HeLa cell monolayer. Pathogenic strains of C. jejuni might be distinguished on HeLa cell monolayer using its sonicated extracts.     

Evaluation of enrichment cultures for detection of Escherichia coli O157 from human stool specimens by using immunomagnetic separation

We investigated the conditions of enrichment cultures preceding the immunomagnetic separation (IMS) procedure to detect Escherichia coli O157 (E. coli O157) from human stool specimens in routine laboratory examinations. Samples were made by adding either of the three selected strains of E. coli O157 to stools from three healthy human subjects in three different doses. The enrichment cultures were done for 18 hours at 37 degrees C or 42 degrees C, using five different media such as trypticase soy broth (TSB). TSB containing cefixime, tellurite and vancomycin, modified EC broth (mEC), mEC containing novobiocin (N-mEC) and BGLB. The IMS procedure following enrichment culture increased the detection rate of E. coli O157, irrespective of the kinds of the media and the temperatures. It recovered E. coli O157 in 42 samples out of 90, while only 31 samples were positive when the IMS was not applied. The N-mEC showed the best recovery rate of the five enrichment media, and it was the only media that recovered the E. coli O157 Gunmma 298 strains at a level of 2-3 cells per ml. In 73 stool samples collected from probable patients with E. coli O157 infection and subjects who made close contact with the patients, positive results were obtained in six samples with the N-mEC enrichment followed by the IMS procedure, while only three samples were positive by the direct isolation culture. It was concluded, therefore, that, in routine laboratory examinations of E. coli O157 from human stools, the N-mEC enrichment culture for 18 hours followed by the IMS procedure is a sensitive method even when the dose of E. coli O157 in the stool is minimal.     

Rheumatic symptoms following an outbreak of campylobacter enteritis: a five year follow up.

Eighty six of 106 (81%) guests attending a party were followed up after an outbreak of Campylobacter jejuni enterocolitis. Acute diarrhoeal illness was reported in 35 subjects (33%), of whom seven showed acute rheumatic symptoms either alone or with other symptoms of infection with C jejuni. The antibody response to C jejuni corresponded well with the intensity of the disease. In the early phase of the gastrointestinal disease the patients with acute rheumatic symptoms displayed significantly higher IgM antibody levels in serum samples than the other patients in this study. Levels of antibodies to C jejuni were increased in serum samples from 31 patients (29%) without symptoms of infection with C jejuni. At a follow up after five and a half years, four of these patients suffered from chronic rheumatic disorders. One HLA-B27 positive woman developed reactive arthritis with a relapse seven years later. The remaining 20 subjects (19%) remained healthy and their antibody tests and stool cultures were negative for C jejuni. It is concluded that C jejuni enterocolitis is significantly associated with rheumatic symptoms in the early phase and may also cause chronic rheumatic disorders.     

空肠弯曲菌共同抗原的提取及应用:SPA协同凝集试验快速检测空肠弯曲菌的实验研究

本文报道一株空肠弯曲菌用甘氨酸提取的共同抗原,能和52种空肠弯曲菌分型血清起交叉反应。用这种共同抗原免疫家兔制备的抗血清致敏SPA后,协同凝集法检测了23株不同血清型的空肠弯曲菌标准株,结果均阳性,而对18株其它肠道菌检测结果均阴性。协同凝集试验与培养法平行检测57份鸡标本,两者均为阳性31份,均阴性14份,总符合率78.9％。无显著性差异。本法具有特异、敏感、快速、简单的特点,便于推广。对临床快速诊断空肠弯曲菌肠炎具有一定价值。     

用不同选择性平板和增菌培养基对空肠弯曲菌分离、传代和增菌的比较试验

本文报告用改良弯曲菌卵黄琼脂平板对来自鸡、猪和人的26株空肠弯曲菌传代后,放4℃冰箱内虽长达7天,少数菌株(7/26)已出现球变,但全能传代生长;而在改良弯曲菌血琼脂平板上至第5天即有部分菌株发生变异,传代中约1/3的菌株(9/26)已不能生长。另用含卵黄的选择性布氏肉汤培养污染于牛奶和光鸡体表的空肠弯曲菌有增菌作用,可以提高其检出效果。     

Campylobacter

Campylobacter is now known to be a major cause of gastrointestinal illness throughout the world. There are seven species known to be associated with enteritis, and it is likely that more will be described. Campylobacter jejuni is responsible for more than 95 per cent of the cases of diarrhea due to Campylobacter. Contaminated food products are the major source of infection. The clinical illness usually involves diarrhea, abdominal pain, and other constitutional symptoms. An accurate diagnosis of Campylobacter enteritis is made when the organism is cultured from the patient's stool. Selective media are widely available, and the isolation of C. jejuni is not difficult. Although erythromycin and the quinolones have good in vitro activity against C. jejuni, antibiotic therapy generally is not indicated.     

Rapid emergence of quinolone resistance in Campylobacter jejuni in patients treated with norfloxacin.

15/60 subjects from one center, who all took part in a multicenter double-blind, placebo-controlled study to evaluate the effect of norfloxacin on acute enteritis, had norfloxacin sensitive strains of Campylobacter jejuni in pre-study stool specimens. Eight of the 15 subjects received active drug. In 3 of these 8, high-level quinolone resistant Campylobacter strains of the same serotype as in pre-treatment samples were isolated 4-90 days after the initiation of treatment.     

Clinical studies on the treatment of Campylobacter enteritis--emergence of quinolone-resistant Campylobacter jejuni after treatment with new quinolones]

In recent years, new quinolones such as ofloxacin (OFLX) and tosufloxacin (TFLX) have been frequently used in the treatment of bacterial enteritis caused by unknown organisms. The agent of first choice for the treatment of Campylobacter enteritis is one of the macrolides, but new quinolones are often administered accidentally to adult patients with Campylobacter enteritis. We have detected quinolone-resistant strains of Campylobacter jejuni (C. jejuni) after the treatment of some patients with new quinolones, and accordingly we reviewed the treatment of Campylobacter enteritis. We experienced 178 adult patients with Campylobacter enteritis from January 1989 to November 1991 at our hospital. From them, we selected 52 patients (32 males and 20 females) in whom stool culture were performed both before and after treatment. The initially administered antimicrobial agent was a macrolide (rokitamycin, RKM) in 6 cases, a new quinolone in 22 cases, and kanamycin (KM) in 24 cases. The new quinolone used was OFLX in 17 cases, TFLX in 3 cases, and norfloxacin (NFLX) in 2 cases. Fifty-one of the 52 C. jejuni strains isolated before treatment were susceptible to OFLX and erythromycin (EM) according to antimicrobial disc susceptibility tests. C. jejuni was eradicated in all patients treated with RKM or KM. However, treatment failed to achieve bacteriological cure in 8/22 (36.4%) patients given new quinolones. In these patients, the strains of C. jejuni isolated before treatment were susceptible to OFLX, but the strains isolated after treatment were all resistant to OFLX according to disc susceptibility tests.(ABSTRACT TRUNCATED AT 250 WORDS)