双歧杆菌三联活菌散/胶囊治疗儿童抗生素相关性腹泻临床疗效的meta分析

采用meta分析评价双歧杆菌三联活菌散/胶囊治疗儿童抗生素相关性腹泻的临床疗效。

系统性地检索中国知网、维普、万方、PubMed、Embase及Web of Science数据库,纳入国内外使用双歧杆菌三联活菌散/胶囊治疗儿童抗生素相关性腹泻的随机对照研究和前瞻性非随机对照临床试验,文献检索时间至2022年6月,筛选所检索文献,提取符合纳入标准的文献数据进行质量评价,采用Cochrane协作网提供的RevMan 5.3软件进行meta分析。

经系统地检索文献,本研究共纳入16项前瞻性非随机对照研究进行meta分析,共计1 415例儿童,meta分析结果显示使用双歧杆菌三联活菌散/胶囊治疗儿童抗生素相关性腹泻的显效率显著高于对照组[OR＝2.58,95% CI（2.03,3.28）,I² = 10%,P＜0.000 1];治疗组的总体有效率也显著高于对照组[OR = 5.80,95% CI（3.80,8.85）,I² = 0%,P＜0.000 1]。

Meta分析评价现有文献结果表明双歧杆菌三联活菌散/胶囊与常规治疗措施相比,能够显著提高儿童抗生素相关性腹泻的显效率和总体有效率,有助于改善患儿临床预后和加速康复。

     

双歧杆菌三联活菌制剂防治儿童呼吸道感染继发腹泻临床疗效的meta分析

采用meta分析评价双歧杆菌三联活菌散/胶囊治疗儿童呼吸道感染继发腹泻的临床疗效。

计算机检索中国知网、维普、万方、PubMed、Web of Science和Embase数据库,收集全球范围内在治疗儿童呼吸道感染继发腹泻中使用双歧杆菌三联活菌制剂（散/胶囊）的随机对照研究和前瞻性非随机对照研究,检索时间截至2022年7月,采用Jadad评分量表对纳入文献进行质量评价,采用Cochrane协作网提供的RevMan 5.4分析软件进行数据处理和meta分析。

纳入19篇公开发表的文献进行meta分析,共3 086例患者,治疗组（对照组常规治疗措施+双歧杆菌三联活菌散/胶囊）1 578例,对照组1 508例,meta分析结果显示,治疗组的总体有效率显著高于对照组[OR = 6.54,95% CI（4.03,10.62）,P＜0.000 01],同时,治疗组的显效率优于对照组[OR=4.21,95% CI（2.97,5.97）,P＜0.000 01],并且,相比于对照组,治疗组的腹泻发病率降低[OR = 0.20,95% CI（0.12,0.34）,P＜0.000 01]）,差异均有统计学意义。

双歧杆菌三联活菌散/胶囊与常规治疗方法相比,可以提高儿童呼吸道感染继发腹泻的治疗总体有效率、治疗显效率,同时有效降低患儿的腹泻发病率。

     

益生菌治疗口腔假丝酵母菌感染效果的meta分析

通过循证医学的方法评价益生菌治疗口腔假丝酵母菌感染的效果。

计算机检索PubMed、EMbase、Web of Science、The Cochrane Library、中国知网、维普数据库、万方数据库和中国生物医学文献数据库中关于益生菌治疗口腔假丝酵母菌感染效果的随机对照试验,检索时限为建库至2021年8月18日,由2名研究者独立对文献进行资料提取和质量评价,采用RevMan 5.4统计软件对提取完成后的资料进行meta分析。

共纳入12篇研究,其中英文研究4篇,中文研究8篇,纳入研究对象1 029人,其中试验组537人,对照组492人。研究结果显示,益生菌能有效治疗口腔假丝酵母菌感染[OR=7.80,95% CI（4.78,12.75）,P＜0.000 1],降低口腔假丝酵母菌检出率[OR=0.06,95% CI（0.01,0.57）,P=0.010 0],降低治愈后复发率[OR=0.21,95% CI（0.12,0.35）,P＜0.000 1]。

益生菌对治疗口腔假丝酵母菌感染具有一定效果,能降低口腔中假丝酵母菌的定植,减低治愈后的复发率。

     

复方嗜酸乳杆菌片治疗幽门螺杆菌感染的Meta分析

系统评价复方嗜酸乳杆菌片治疗幽门螺杆菌感染的有效性、安全性。

以“复方嗜酸乳杆菌片”“幽门螺杆菌感染”“Compound Eosinophil-Lactobacillus Tablets”“Helicobacter pylori infection”为主题词, 系统检索The Cochrane Library、PubMed、Springer、ProQuest、中国知网、万方和维普等数据库(建库-2020年5月)的随机对照试验文献。利用RevMan 5.3软件对复方嗜酸乳杆菌片的有效性、安全性进行Meta分析。

依据严格的纳入排除标准, 最终纳入18篇随机对照试验文献。Meta分析结果显示: 复方嗜酸乳杆菌片与一线治疗方案联合用药治疗幽门螺杆菌感染临床疗效更优[RR=0.84, 95%CI(0.80, 0.87), P < 0.000 01], 安全性更好[OR=2.83, 95%CI(2.30, 3.49), P < 0.000 01]。进一步亚组分析表明, 复方嗜酸乳杆菌片与四联疗法联合用药治疗幽门螺杆菌感染与四联疗法相比, 临床疗效更优[RR=0.88, 95%CI(0.83, 0.93), P < 0.000 01], 安全性更优[OR=2.58, 95%CI(1.92, 3.48), P < 0.000 01];复方嗜酸乳杆菌片联合三联疗法治疗幽门螺杆菌感染较三联疗法临床疗效更优[RR=0.81, 95%CI(0.76, 0.85), P < 0.000 01], 且安全性好[OR=3.09, 95%CI(2.31, 4.14), P < 0.000 01]。

基于现有文献, 在治疗幽门螺杆菌感染时, 复方嗜酸乳杆菌片与四联疗法或三联疗法联合用药具有一定的临床优势, 能提高幽门螺杆菌根除率, 降低不良反应发生率, 提高安全性。

     

轻度胃肠炎伴热性惊厥患儿肠道菌群失调与脑损伤的相关性

探讨热性惊厥患儿肠道菌群失调与脑损伤的相关性,为该类患儿的治疗提供参考。

选取2020年10月至2021年10月我院收治的108例热性惊厥患儿为研究对象,根据患儿临床表现分为轻度胃肠炎伴热性惊厥组（57例）和单纯型高热惊厥组（51例）;根据是否发生脑损伤分为脑损伤组（27例）与无脑损伤组（81例）。入院时采集患儿粪便标本进行轮状病毒检测以及大肠埃希菌、肠球菌、乳杆菌和双歧杆菌培养。采集患儿空腹静脉血,采用酶联免疫双抗体夹心法检测血清S-100β蛋白、碱性髓鞘蛋白（myelin basic protein,MBP）、神经元特异性烯醇化酶（neuron-specific enolase,NSE）水平。采用多因素Logistic回归分析影响热性惊厥患儿脑损伤的危险因素,然后采用Pearson法分析肠道菌群与脑损伤的相关性。

轻度胃肠炎伴热性惊厥组患儿轮状病毒阳性28例（49.12%）,单纯型高热惊厥组患儿轮状病毒阳性15例（29.41%）,差异有统计学意义（χ² = 4.364,P＜0.05）。轻度胃肠炎伴热性惊厥组患儿粪便中大肠埃希菌、肠球菌、乳杆菌、双歧杆菌数量均低于单纯型高热惊厥组（均P＜0.05）。轻度胃肠炎伴热性惊厥组患儿血清S-100β蛋白、MBP、NSE水平均高于单纯型高热惊厥组（均P＜0.05）。单因素分析显示,脑损伤组患儿首次发热体温以及粪便中大肠埃希菌、肠球菌、乳杆菌、双歧杆菌数量低于无脑损伤组患儿,而血清S-100β蛋白、MBP、NSE水平高于无脑损伤组患儿（均P＜0.05）。多因素Logistic回归分析显示,大肠埃希菌数量降低（OR = 2.063,95% CI：1.252～2.919）、肠球菌数量降低（OR = 1.912,95% CI：1.252～2.919）、乳杆菌数量降低（OR = 2.032,95% CI：1.083～3.812）、双歧杆菌数量降低（OR = 2.044,95% CI：1.235～9.593）、血清S-100β蛋白水平升高（OR = 3.442,95% CI：1.235～9.593）、血清MBP水平升高（OR = 3.149,95% CI：1.222～8.115）、血清NSE水平升高（OR = 2.815,95% CI：1.752～4.524）是影响热性惊厥患儿脑损伤的独立危险因素（均P＜0.05）。Pearson相关性分析结果显示,血清S-100β蛋白、MBP、NSE水平与粪便中大肠埃希菌、肠球菌、乳杆菌、双歧杆菌数量呈负相关（均P＜0.05）。

轮状病毒感染,肠道菌群失衡,有益菌数量降低与轻度胃肠炎伴热性惊厥患儿发病和脑损伤密切相关,调节轻度胃肠炎伴热性惊厥患儿肠道菌群对该病的防治具有积极意义。

     

呼吸道合胞病毒下呼吸道感染与患儿鼻咽部定植菌群的关系

研究鼻咽部定植菌群与呼吸道合胞病毒（RSV）下呼吸道感染患儿病情特点的关系,从微生态角度寻找预防或治疗RSV下呼吸道感染的理论依据。

回顾性分析我院2020年8月1日到2021年10月31日收治的RSV下呼吸道感染患儿,根据鼻咽部分泌物培养结果分为阴性组、阳性组,对比两组患儿临床特点及潮气肺功能检测结果。

1 090例RSV下呼吸道感染患儿中培养阳性者290例（26.58%）,中位数年龄为8个月（3.24个月,14个月）。各年龄层患儿鼻咽部菌群定植率及定植菌群差异有统计学意义（均P＞0.05）。各年龄层患儿鼻咽部定植菌均以肺炎链球菌为主。金黄色葡萄球菌、大肠埃希菌及卡他莫拉菌定植的患儿发热率较低。与喘息相关定植菌为肺炎链球菌、流感嗜血杆菌及金黄色葡萄球菌。与重症相关的定植菌为肺炎链球菌、流感嗜血杆菌、金黄色葡萄球菌、大肠埃希菌。与大叶性肺炎发生相关的只有肺炎链球菌。肺炎链球菌及流感嗜血杆菌定植的达峰容积比（Z = −4.12,P＜0.001;Z = −1.99,P = 0.046）与达峰时间比（Z = −4.24,P＜0.001;Z = −1.98,P = 0.047）均低于阴性组。

特定鼻咽部定植菌的存在会影响RSV下呼吸道感染患儿的临床表现,同时降低婴幼儿潮气肺功能检测结果。

     

益生菌联用泻药对中国成人功能性便秘的疗效——基于随机对照试验的Meta分析

探讨国内益生菌联合泻药对于成人功能性便秘的疗效。

以“益生菌”和“功能性便秘”为关键词, 分别在中国知网、维普、万方数据库、中国生物医学文献数据系统、PubMed、Embase和Cochrane Library检索益生菌联合泻药对功能性便秘的疗效, 检索时限从建库至2020年12月6日。采用Stata 13.1和RevMan 5.4软件进行Meta分析。

共检索出16 929篇文献, 最终纳入23篇文献。联合组在有效率[OR=4.39, 95%CI=(3.25, 5.92), P < 0.000 01]、排便频率改善[WMD=0.77, 95%CI=(0.16, 1.38), P < 0.000 01]、粪便性状改善[WMD=1.12, 95%CI=(0.87, 1.37), P < 0.000 01]等方面均优于对照组。

益生菌联合泻药比单用泻药更能有效缓解便秘。

     

急性心肌梗死并发肺部感染患者的临床特点和病原菌特征及危险因素分析

分析急性心肌梗死（AMI）并发肺部感染患者的临床特点、病原菌特征及危险因素,为该类患者的治疗提供参考。

选择2019年1月至2021年1月海安市人民医院收治的96例AMI患者作为研究对象,并根据患者在治疗过程中是否并发肺部感染将其分为感染组（40例）和非感染组（56例）。采集患者痰液标本并对感染病原菌进行鉴定,同时观察肺部感染患者的临床特点。采用多因素Logistic回归分析探讨AMI患者并发肺部感染的危险因素。

96例AMI患者中存在40例肺部感染,共检出病原菌22株,其中革兰阴性菌14株（占63.64%）,革兰阳性6株（占27.27%）,真菌2株（占9.09%）。与非感染组比较,感染组患者血红蛋白、白蛋白、总蛋白水平较低,降钙素原、超敏C反应蛋白、肿瘤坏死因子-α水平较高（均P＜0.05）。单因素分析显示,AMI患者并发肺部感染与年龄、卧床时间、有无慢性阻塞性肺疾病、有无侵入性操作存在显著关联（均P＜0.05）。多因素Logistic回归分析显示,年龄≥60岁（OR = 3.71,95%CI：1.62～8.49）、卧床时间≥2周（OR = 3.42,95%CI：2.12～5.54）、慢性阻塞性肺疾病（OR = 2.68,95%CI：2.19～3.29）、侵入性操作（OR = 3.40,95%CI：2.69～4.30）及低蛋白血症（OR = 1.37,95%CI：1.09～1.74）均为AMI患者并发肺部感染的相关因素（均P＜0.05）。

AMI患者并发肺部感染的病原菌以革兰阴性菌为主,其次为革兰阳性菌;年龄、卧床时间、慢性阻塞性肺疾病、侵入性操作及低蛋白血症均为AMI患者并发肺部感染的独立危险因素。

     

精神分裂症患者肠道菌群特征与认知损害的关系

观察精神分裂症患者肠道菌群特征,并分析其与认知损害的关系。

选择2020年3月至2022年3月我院收治的175例精神分裂症患者作为研究对象。所有患者入院时均接受轻度认知损害筛查量表（sMCI）评估,根据认知损害发生情况,分为认知损害组和非认知损害组。统计两组患者一般资料和肠道菌群特征,分析精神分裂症患者肠道菌群特征与认知损害的关系。

175例精神分裂症患者中出现认知损害91例（52.00%）,未出现认知损害84例（48.00%）。认知损害组患者sMCI评分低于非认知损害组（P＜0.05）。两组患者肠道菌群α多样性比较差异无统计学意义（均P＞0.05）。两组对象肠道菌群的特征性物种在门水平为拟杆菌门（LDA = 2.54）,厚壁菌门（LDA = 4.25）;在纲水平为拟杆菌纲（LDA = 3.57）,梭菌纲（LDA = 4.31）;在科水平为产碱杆菌科（LDA = 4.23）和梭菌科（LDA = 2.76）;在属水平为萨特菌属（LDA = 3.18）。认知损害组患者肠道拟杆菌门丰度高于非认知损害组,厚壁菌门丰度低于非认知损害组;拟杆菌纲丰度高于非认知损害组,梭菌纲丰度低于非认知损害组;产碱杆菌科丰度高于非认知损害组,梭菌科丰度低于非认知损害组;萨特菌属丰度高于非认知损害组（均P＜0.05）。Logistics回归分析显示,高丰度的拟杆菌门、拟杆菌纲、产碱杆菌科、萨特菌属是精神分裂症患者发生认知损害的危险因素（OR＞1,均P＜0.05）;高丰度的厚壁菌门、梭菌纲是精神分裂症患者发生认知损害的保护因素（OR＜1,均P＜0.05）。

精神分裂症患者肠道菌群结构显著失衡,且部分菌群丰度与认知损害密切相关。

     

急性脑卒中患者肠道菌群研究

通过粪便标本检测急性脑卒中患者肠道菌群变化情况, 探讨急性脑卒中患者肠道菌群结构。

通过高通量二代测序技术对10例健康者(对照组)及10例急性脑卒中患者(疾病组)粪便样本进行菌群结构测序分析。

与对照组比较, 急性脑卒中患者粪便样本中物种OTU信息量显著增加(P < 0.01), 菌群多样性指数(Shannon)和物种均一度指数(Evenness)也有所增加但差异无统计学意义(均P > 0.05)。门水平上, 疾病组患者肠道Bacteroidetes数量较对照组显著增加, Firmicutes数量显著减少(均P < 0.05)。属水平上, 疾病组患者肠道Bacteroides、Bilophila、Butyricimonas比例较对照组显著升高, 而Collinsella、Coprococcus、Clostridium等比例较对照组显著降低(均P < 0.05)。

急性脑卒中患者肠道菌群结构与健康人存在显著差异。

     

Prevalence of Clostridium spp. and Clostridium difficile in children with acute diarrhea in São Paulo city,Brazil

Species of Clostridium are widely distributed in the environment, inhabiting both human and animal gastrointestinal tracts. Clostridium difficile is an important pathogen associated with outbreaks of pseudomembranous colitis and other intestinal disorders, such as diarrhea. In this study, the prevalence of Clostridium spp. and C. difficile, from hospitalized children with acute diarrhea, was examined. These children were admitted to 3 different hospitals for over 12 months. Eighteen (20%) and 19 (21%) stool specimens from children with (90) and without (91) diarrhea respectively, were positive to clostridia. Only 10 C. difficile strains were detected in 5.5% of the stool samples of children with diarrhea. None healthy children (without diarrhea) harbored C. difficile. From these 10 C. difficile, 9 were considered as toxigenic and genotyped as tcdA+/tcdB+ or tcdA-/tcdB+, and 1 strain as nontoxigenic (tcdA-/tdcB-). They were detected by the citotoxicity on VERO cells and by the multiplex-polymerase chain reaction. Thirty clinical fecal extracts produced minor alterations on VERO cells. The presence of C. difficile as a probable agent of acute diarrhea is suggested in several countries, but in this study, the presence of these organisms was not significant. More studies will be necessary to evaluate the role of clostridia or C. difficile in diarrhoeal processes in children.     

Clostridium difficile-associated diarrhea from a general hospital in Argentina

Clostridium difficile is responsible for 15-25% of all cases of antibiotic associated diarrhea. The incidence of infection with this organism is increasing in hospitals worldwide, consequent to the widespread use of broad-spectrum antibiotics. Although the clinical and financial impact of nosocomial C. difficile infection is believed to be significant, only limited information is available on the importance of C. difficile as a cause of diarrhea in Argentina. The aim of the study was to evaluate the impact and diagnosis methods of CDAD from symptomatic patients in a general hospital from Argentina. Consecutive diarrheal stool samples from symptomatic patients from a General Hospital in Argentina were screened for toxigenic C. difficile between April 2000 and April 2001. Toxins were detected in stools by the Premier Cytoclone A+B EIA. Each specimen was examined for toxigenic C. difficile strains by culture. From 104 specimens, 40 (38.5%) [32 of 87 patients (36.8%)] were positive and 64 (61.5%) [55 of 87 patients (63.2%)] were negative by stool toxin assay and/or toxigenic culture. In 11 of 40 positives samples C. difficile toxins were detected only by toxigenic culture. Five (15.6%) patients presented with symptomatic recurrences. Toxin-negative strains were not isolated. This data indicates that the high prevalence of toxigenic strains of C. difficile is of concern in routine diagnostic testing for C. difficile toxins in our study population. Detection of toxins in stools by EIA, coupled with testing strains for toxigenicity only in those cases in which direct toxin assay produces negative results, may be a satisfactory strategy. CDAD is an emerging nosocomial problem in our hospital. It will be necessary to evaluate the epidemiology and measures to control nosocomial spread.     

Cytotoxicity and antimicrobial susceptibility of Clostridium difficile isolated from hospitalized children with acute diarrhea

Clostridium difficile is an important pathogen associated with outbreaks of pseudomembranous colitis and other intestinal disorders such as diarrhea. In this study, 181 stool samples from children with and without acute diarrhea were analysed. Eighteen children with acute diarrhea were positive to C. ramosum, C. difficile, C. limosum, C. clostridioforme, C. septicum, C. butyricum, C. innocuum and Clostridium sp. Nineteen children without diarrhea harbored C. ramosum, C. septicum, C. barattii, C. butyricum, C. innocuum, C. sphenoides, C. bifermentans, C. clostridioforme and C. paraputrificum. No patient with diarrhea harbored C. barattii, C. bifermentans, C. paraputrificum and C. sphenoides. In addition, ten C. difficile strains were detected in 5 (5.5%) of the children with diarrhea. Also, no children from control group harbored C. difficile, C. limosum and Clostridium sp. Most of the tested strains were resistant to all the used antimicrobial. Nine C. difficile were toxigenic on VERO cells and by multiplex PCR, six strains showed both toxin A and B genes and three strains showed only toxin B gene. In this study, the presence of C. difficile was not significant, and it is suggested the need of more studies to evaluate the role of clostridia or C. difficile play in the childhood diarrhea and these organisms must be looked for routinely and a periodic evaluation of antimicrobial susceptibility should be performed.     

Effect of various sodium taurocholate preparations on the recovery of Clostridium difficile spores

The effect of four sodium taurocholate preparations, which are easily available in Japan, on recovery of Clostridium difficile spores was examined. All preparations, except for one, enabled the recovery of nearly all spores counted microscopically. Moreover, by using 69 toxigenic and 34 nontoxigenic C. difficile strains, the relationship between the recovery of spores in the medium with sodium taurocholate and toxigenicity of C. difficile was analyzed. It was noted that the number of strains with recovery rate of more than 70% was greater in toxigenic strains than in nontoxigenic strains, suggesting a more abundant recovery of toxigenic C. difficile strains in the presence of sodium taurocholate.     

Laboratory diagnosis of Clostridium difficile associated diarrhoea and molecular characterization of clinical isolates

We evaluated a three-step algorithm for laboratory diagnosis of Clostridium difficile-associated diarrhoea (CDAD). First, stool specimens were screened using an EIA test for glutamate dehydrogenase detection. Screen-positive specimens were tested by a rapid cytotoxintoxin A/B assay and subjected to stool culture. All cultures positive for C. difficile underwent toxigenic culture. The results showed that toxigenic culture allowed us to recover 37/156 (24.4%) stool samples harbouring toxigenic C. difficile that would have been missed by using faecal cytotoxin assay alone. This determined an increase in infection prevalence of 4.2% (from 11.4% to 15.6 %). Furthermore, to characterize the clinical Clostridium difficile isolates and the distribution of PCR ribotypes circulating in the San Carlo Borromeo hospital, molecular typing using semi-automated repetitive-sequence-based PCR (rep- PCR) and PCR ribotyping, and an evaluation of the antibiotic resistance were also performed. Among them, 71 indistinguishable strains were detected by rep-PCR and 83 by PCR-ribotyping revealing C. difficile outbreaks in our hospital. A total of 6 different ribotypes were obtained by PCR ribotyping. The most frequent ribotype was 018 (88.2%) that also showed resistance to moxifloxacin. In one case, uncommon PCR ribotype 186 was also identified.     

兰州市婴幼儿艰难梭菌带菌状况

在兰州市随机采集的２１６名健康婴幼儿粪标本经分离并对其培养特性、菌落菌体形态特征、生化反应特性以及毒素原性等进行一系列检查,检出了３７人的粪便含有艰难梭菌（１０４─１０８／ｇ）,检出总阳性率为１７．１％,新生儿、婴儿及幼儿各年龄组的检出阳性率分别为１３．５％（１９／４１）、３３．３％（１３／３９）、１３．９％（５／３６）。３７株分离菌中毒素原性阳性者仅有８株（２１．６％）,均分布于婴儿与幼儿两组。新生儿１４１人中２７人的粪标本为胎粪,只有１人（３．７％）含艰难梭菌（２×１０６／ｇ）,但不产毒素。所有婴幼儿中有２２人因各种原因曾用过抗菌药物,但仅有２人的粪便含艰难梭菌,而且均为非产毒株,表明艰难梭菌检出率与药物服用之间似无显著的相关性。     

Evaluation of different methods for detection of Clostridium difficile toxins in Poland

The aim of this study was to compare different methods for C. difficile toxins detection. Fifty three stool samples taken from patients with antibiotic-associated diarrhoea were studied. TCD toxin A EIA (Becton Dickinson, USA), Tox A/B ELISA test (TechLab, USA), cytotoxicity and neutralization assay on McCoy cells and PCR for detection of both toxin A and B genes were performed in vivo (in stool samples) and in vitro (in isolated strains). Reference toxigenic and nontoxigenic and two Japanese toxin A-negative and toxin B-positive C. difficile strains were used as a controls. TCD toxin A EIA detected in vivo only 19 positive samples. Tox A/B test detected 52 positive samples out of 53 studied. All 53 stool samples were C. difficile culture positive (53 strains were cultured). Toxin B was detected in 52 strain-supernatants and in all controls (except the nontoxigenic one). Both toxin A and B genes were detected by PCR in all 53 isolated strains, Japanese and reference strain (except the nontoxigenic one). In vitro toxin A was detected by TCD toxin A EIA in 42 strains. These results were compared with those obtained in Tox A/B ELISA test. We observed 52 positive strains. Toxigenic reference strain and two Japanese toxA(-)/toxB(+) strains were also positive. Only 2 negative results were obtained with the nontoxigenic reference strain and unique nontoxigenic isolated strain. Tox A/B ELISA test seems to be the best for detection of C. difficile toxins in vivo and in vitro. Test avoids the false-negative results in the case of presence of toxin A-negative and toxin B-positive strain.     

Clostridium difficile in emergency room

Clostridium difficile strains are known as etiological agents of pseudomembranous colitis (PMC), antibiotic-associated diarrhea (AAC) and colitis (AAC) and hospital-acquired infections. The aim of this study was to determine the frequency of C. difficile infection among patients in the emergency room and to compare isolated strains by phenotypic and genotypic characteristics. During a period of 11 months, 56 stool samples taken from diarrheic patients hospitalized in the emergency room of the Medical Center UC Davis and 14 environmental samples were cultured for isolation of C. difficile strains. Eighteen C. difficile strains were isolated from stool samples cultured on selective TCCCA plates and 5 strains from environmental samples using Rodac plates. Eleven toxigenic (TcdA+/TcdB+), 6 non-toxigenic (TcdA-/TcdB-) and unique toxin A-negative/toxin B-positive (TcdA-/TcdB+) C. difficile strains were detected among patients' isolates and 3 toxigenic and 2 non-toxigenic strains-among environmental samples. The majority of C. difficile-positive patients were treated previously by antibiotics. Four strains isolated from patients' fecal samples and one strain isolated from the environment demonstrated high-level resistance to erythromycin and clindamycin (MIC >256mug/mL). The results obtained by AP-PCR and PCR-ribotyping revealed genetic heterogeneity among the strains isolated from patients' fecal samples. However, similarity was observed among environmental strains and strains isolated from patients' fecal samples. Considering the importance of emergency room patients as a potential source of C. difficile strains, it appears to be important examine these patients for C. difficile before transfer to the other hospital units.     

粪便标本艰难梭菌三种培养方法的比较

目的 比较粪便标本中艰难梭菌三种培养方法的差异性,寻找适合临床实验室使用的艰难梭菌培养方法。方法 将健康儿童的300份粪便标本分别用快速芽孢孵育法、乙醇直接处理法、富集芽孢培养法进行培养,并对三种培养方法的差异性进行统计学比较。结果 300份粪便标本快速芽孢孵育法培养出艰难梭菌51例,检出率为17.0%;乙醇直接处理法培养出48例,检出率为16.0%;富集芽孢培养法培养出44例,检出率为14.7%。三种方法的检出率差异无统计学意义（P=0.7352,P>0.05）。结论 乙醇直接处理法、快速芽孢孵育法简单快速,适合临床实验室进行艰难梭菌的快速培养;富集芽孢培养法杂菌少,适合大量艰难梭菌培养便于结果的观察及进一步的处理。     

Occurrence of Clostridium difficile in fecal samples of HIV-infected children in Poland

The prevalence of Clostridium difficile and its toxins (A and B) in HIV-positive children in Poland was investigated in a group of 18 children, aged 6 months to 8 1/2 years. Stool samples were tested using an antigen detection method for toxin A/B, cytotoxicity-neutralization and culture. In 3 cases (17%) C. difficile toxins were detected in both stool samples and strains recovered from culture. The three strains isolated were shown by PCR methods to contain toxins A and B genes. All children had been treated previously with antimicrobial and antiviral agents. All three C. difficile-positive children had mild diarrhea that resolved without specific therapy. Further studies involving a large number of children and molecular analyses of isolated C. difficile strains are necessary to determine the frequency and rate of carriage of C. difficile strains among HIV-positive children in Poland.