沈阳地区孕晚期妇女携带B群链球菌不同血清型的调查研究

目的:调查沈阳地区孕晚期妇女携带B群链球菌(GBS)不同血清型分布情况及各型别间的耐药差异。方法:选取2016年5月—2017年8月于沈阳市妇婴医院产科就诊的19 122例孕晚期妇女中经细菌鉴定为GBS阳性,以居住沈阳地区3年以上的孕妇携带的GBS纯培养菌株为标本。通过聚合酶链反应(PCR)和基因测序确定GBS的血清型,比较不同GBS血清型的耐药率和胎膜早破发生率。结果:19 122例孕晚期妇女中GBS阳性者572例,GBS携带率为3.0%。源自沈阳地区的251株纯培养菌株中,GBS血清型以Ⅰa(44.22%)、Ⅴ(38.65%)、Ⅲ(13.94%)为主,并发现与血清型Ⅴ具有高度同源性的血清型NT。未发现血清型Ⅰa、Ⅲ、Ⅴ和NT存在对青霉素、氨苄西林、万古霉素、美罗培南、利奈唑胺耐药菌株。红霉素、克林霉素、左氧氟沙星和四环素对4个血清型的耐药率差异无统计学意义(均P0.05)。血清型Ⅰa、Ⅲ、Ⅴ对红霉素、克林霉素、左氧氟沙星和四环素4种药物的耐药率差异有统计学意义(P0.05),而血清型NT对4种药物的耐药率差异无统计学意义(P0.05)。携带Ⅰa、Ⅲ、Ⅴ和NT 4个不同血清型的孕晚期妇女胎膜早破发生率分别为23.42%、34.28%、10.31%和25.00%,差异有统计学意义(χ2=11.128,P=0.011)。结论:沈阳地区GBS携带率为3.0%,血清型Ⅰa、Ⅴ和Ⅲ为主,且各血清型间不存在耐药差异。应重视孕晚期妇女GBS的筛查工作,根据筛查结果针对性地给予抗感染治疗,减少不良妊娠结局的发生。     

围生期孕妇生殖道B族链球菌耐药性变迁及血清型分布研究

目的：了解西安地区孕产妇生殖道B族链球菌（group B Streptococcus,GBS）的血清型分布特征及GBS对常规抗菌药物的耐药谱,为临床预防与治疗提供依据。方法：收集2015年1月—2017年12月在西北妇女儿童医院产科接受产前GBS筛查的孕晚期孕妇阴道拭子培养出的GBS共498株。采用多重聚合酶链反应（PCR）方法测定GBS血清型,并进行药物敏感性试验和表型筛查试验。结果：所有GBS分离株均对青霉素、头孢曲松、万古霉素、利奈唑胺敏感。GBS对红霉素、克林霉素及左氧氟沙星耐药率分别为76.7%、73.5%和58.0%,且红霉素的耐药率呈逐年上升趋势。表型为结构型耐药（cMLSB）的GBS菌株占红霉素耐药菌株的首位（88.2%）,而诱导型耐药（iMLSB）和M型耐药菌株仅占耐药株的5.5%和6.3%。最常见的血清型为Ⅲ型,其次为Ⅰa 型、Ⅴ型、Ⅰb 型、Ⅱ型和Ⅵ型。结论：①西安地区孕产妇生殖道GBS定植率与我国其他地区相似或略低;②血清型Ⅲ占主要地位;③红霉素、克林霉素、左氧氟沙星耐药率高于其他地区,且红霉素耐药率呈逐年上升趋势。     

孕晚期阴道定植B族链球菌的血清型特点及其与新生儿早发型感染的相关性

目的探讨孕晚期阴道定植B族链球菌(group B Streptococcus,GBS)的血清型特点,及其与新生儿早发型GBS感染(early-onset GBS disease,GBS-EOD)的相关性。方法收集2016年6月至2018年6月在厦门市妇幼保健院新生儿科住院的孕妇阴道GBS定植阳性的32例新生儿GBS-EOD的菌株,并按12∶1的比例抽取同期建卡并分娩的孕晚期阴道GBS定植菌株266例。总共获得298例来自母亲阴道定植的菌株和32例来自新生儿的菌株。用乳胶凝集法测定菌株血清型。分析GBS 11种血清型的感染情况和孕妇阴道定植GBS血清型与新生儿GBS-EOD的相关性。采用χ2检验或Fisher精确概率法,相关系数用列联系数C表示,多个样本率的多重分析采用Post hoc检验,根据调整后的标化残差判断各组的差异。结果298例孕晚期阴道GBS定植菌株总共发现9个血清型。按定植率高低依次为Ⅲ型55.0%(164/298),Ⅰb型16.4%(49/298),Ⅰa型11.1%(33/298),Ⅴ型9.4%(28/298),Ⅱ型5.0%(15/298),不可分(non-typeable,NT)型1.0%(3/298),Ⅵ、Ⅷ和Ⅸ型各0.7%(2/298)。Ⅳ、Ⅶ型则未见定植。32例GBS-EOD总共发现5种血清型,按发病率高低依次为Ⅲ型56.3%(18/32),Ⅰa型25.0%(8/32),Ⅰb型9.4%(3/32),Ⅱ型6.2%(2/32),Ⅴ型3.1%(1/32)。Ⅲ型GBS在新生儿肺炎、败血症和脑膜炎的分布比例分别为6/13、7/14和5/5。5种血清型在上述3种疾病中的分布差异无统计学意义(Fisher精确概率法,P=0.654)。32例患儿中,30例(93.7%)治愈,2例(6.3%)死亡。Ⅰa、Ⅰb、Ⅱ、Ⅲ型和其他血清型(指Ⅴ、Ⅵ、Ⅷ、Ⅸ和NT型)在垂直传播造成新生儿GBS-EOD方面的差异有统计学意义(P=0.046,列联系数C=0.183)。进一步分析发现,Ⅰa型调整后的标化残差绝对值最大(2.7),差异有统计学意义;Ⅲ型无统计学意义。结论孕晚期阴道定植GBS及新生儿GBS-EOD的血清型中,Ⅲ型最为常见,也是早发型脑膜炎主要的血清型,但Ⅰa型垂直传播率最高。Ⅲ型和Ⅰa型是毒力最强的血清型。     

B族链球菌规律成簇间隔短回文重复序列与基因分型及耐药基因的关系

目的探讨孕晚期孕妇生殖道定植及侵袭性感染患儿的B族链球菌(group BStreptococcus, GBS)规律成簇间隔短回文重复序列(clustered regularly interspaced short palindromic repeats, CRISPR)分布及其与多位点序列分型(multilocus sequence typing, MLST)、耐药基因的关系。方法回顾性收集2017年1月至2022年1月山西医科大学附属儿童医院(山西省妇幼保健院)收治的孕晚期孕妇定植GBS及GBS侵袭性感染患儿临床分离的84株GBS菌株(包括侵袭性菌株17株、定植菌株67株), 检测其CRISPR、MLST、耐药表型及耐药基因。采用χ2检验或Fisher精确概率法进行统计分析, 并采用MEGA11构建发育树图。结果 84株中共有10种ST型别, 最常见的是ST10(46.4%)。GBS对青霉素敏感, 对红霉素和克林霉素的耐药率分别为75.0%和73.8%;17株GBS侵袭性菌株中, ST10型对红霉素、克林霉素以及左氧氟沙星耐药率达100%。62株检出CRISPR1基因, 阳性率为73...     

孕35~37周妇女无乳链球菌携带状况及耐药性分析

目的了解孕晚期女性生殖道无乳链球菌携带状况及菌株耐药性,为新生儿无乳链球菌感染合理抗生素预防、治疗提供依据。方法连续收集北京大学深圳医院2013年1月-12月产检门诊孕35~37周女性阴道分泌物,采用肉汤增菌、细菌分离培养及鉴定技术对无乳链球菌进行分离鉴定,采用K-B法测定无乳链球菌对7种常用抗生素的敏感性,对体外药敏试验表现为红霉素耐药而克林霉素敏感或中介的菌株加做D试验。结果共收集阴道分泌物拭子1 305例,分离鉴定出无乳链球菌157株,分离率为12.0%。157株无乳链球菌对青霉素、万古霉素、头孢曲松3种药物的敏感率均为100%;对四环素的耐药率为72.6%,对红霉素、克林霉素、左氧氟沙星的耐药率分别为56.7%、47.8%、31.2%;其中5株D试验阳性。结论无乳链球菌对青霉素、万古霉素、头孢曲松高度敏感,青霉素可作为分娩期抗生素预防的首选药,四环素、红霉素、克林霉素耐药率较高,应根据其体外药敏结果选择用药。     

妊娠晚期B族链球菌的感染现状和耐药情况及阴道微生态情况分析

目的:探讨妊娠晚期孕妇B族链球菌(GBS)的感染现状、耐药情况及GBS感染阴道微生态情况。方法:回顾性分析2020年1月至2022年12月在唐山市妇幼保健院接受产检的37175例妊娠晚期孕妇病例资料,统计GBS培养和药敏试验结果,分析连续3年内不同年龄段孕妇GBS的感染情况、变化趋势及耐药率变迁。同时对2022年1月至2022年12月就诊的849例妊娠晚期孕妇的生殖道标本进行细菌培养及形态学检测(分为GBS阳性组499例和GBS阴性组350例),观察并比较两组的清洁度和微生态指标的特点。结果:2020年1月至2022年12月连续3年,GBS阳性率分别为4.30%、4.79%、5.14%,且逐年增高(P<0.01);不同年龄组GBS检出阳性率的差异无统计学意义(P>0.05);连续3年GBS对青霉素、氨苄西林、阿莫西林/克拉维酸、头孢曲松钠、头孢噻肟、头孢吡肟、美罗培南、利奈唑胺、万古霉素均未发现耐药菌株,对左氧氟沙星、红霉素、克林霉素耐药率较高(均>50%),但耐药率呈下降趋势。对四环素的耐药率较高且耐药率呈上升趋势;在阴道微生态方面,GBS阳性组和GBS阴性组阴道微...     

B组链球菌血清型分布和抗生素敏感性试验研究

目的　获得在中国北京地区 B组链球菌 (GBS)血清学型分布特点和抗生素耐药菌谱情况。　方法　 76株 GBS分别由待产产妇和正常妇女阴道拭子分离培养并经协同凝集 (COA)抗原检测明确所获。采用标准 L ancefiled方法对所获 76株 GBS进行血清学分型 ;采用标准的琼脂稀释法对其中 47株 GBS进行抗生素最小抑菌浓度 (MIC)测定。　结果　 76株 GBS菌可分为 7个血清型 ,其中 II(33% )、III(2 3% )、Ia(16 % )是主要血清型 ,10 0 % GBS对青霉素类、头孢菌素类和红霉素敏感。青霉素和氨苄青霉素 MIC均≤ 0 .0 6 μg/ ml,头孢唑啉、头孢呋新、头孢哌酮 MIC范围为 0 .0 0 6～ 0 .0 3μg/ m l;红霉素 MIC是 0 .0 0 3～ 0 .0 3μg/ ml,庆大霉素 MIC1～ 32 μg/ m l,丁胺卡那霉素 MIC4～≥ 6 4μg/ ml。他们的耐药率分别是 12 .8%和 40 .4%。　结论　该结果为在我国进一步研究优势荚膜多糖菌苗进行免疫预防 GBS感染及对指导临床医师合理选择抗生素治疗 GBS感染提供了重要的理论依据 ,实验室常规报告 GBS敏感性结果 ,对 GBS菌株连续药物敏感性监测 ,了解耐药变迁情况也具有重要临床意义     

围产期生殖道感染B族溶血性链球菌的耐药性及耐药基因检测

B族溶血性链球菌(group B strePtococci,GBS)是围产期严重感染性疾病的主要致病菌之一,可引发胎膜早破、晚期流产、早产、胎儿生长受限等一系列母婴不良结局,因而被欧美国家列为围产期感染的首要病原菌之一[1].为探讨围产期感染的GBS菌株的耐药性及耐药基因携带情况,本研究对围产期感染GBS菌株进行耐药性分析并检测多种耐药基因,现将结果报道如下.     

育龄期精液和孕妇生殖道分泌物B族链球菌定植和耐药性分析

目的 分析育龄期精液和孕妇生殖道分泌物中B族链球菌（GBS）定植及耐药性情况,指导临床干预治疗。方法 采集生殖中心人工辅助受精精液标本和门诊产前诊断中心、产科孕妇生殖道分泌物标本,进行培养分离和耐药性分析。结果 4480例精液标本检出GBS 369株,定植率为8.24%,2019年、2020年、2021年定植率分别为5.80%、7.44%、10.63%。2157例孕妇生殖道分泌物标本检出GBS 122株,定植率为5.66%,2019年、2020年、2021年定植率分别为6.22%、5.96%、4.73%。所有GBS对青霉素、万古霉素、氨苄西林、利奈唑胺和奎奴普汀/达福普汀全敏感,对克林霉素、红霉素和四环素的耐药率较高,对左氧氟沙星、莫西沙星的耐药率相对较低。结论 育龄期精液GBS定植呈上升趋势,而孕妇生殖道分泌物GBS定值率呈下降趋势。临床干预治疗应重视药敏试验结果合理选用抗菌药物,首选药物为青霉素和氨苄青霉素。     

妊娠期妇女B族链球菌感染对母儿预后影响的研究

目的探讨妊娠期妇女B族链球菌(GBS)感染对新生儿危害及母儿预后的影响。方法选取2014年6月至2016年7月曲靖市第一人民医院产科门诊接受产检的35~37周3000例待产孕妇阴道和直肠分泌物及分娩后新生儿的脐带血。分别采用实时荧光定量PCR(QF-PCR)法和细菌培养法对分泌物及新生儿脐带血进行GBS检测。分析GBS感染对围产期母儿预后的影响。结果 GBS在阴道及直肠的总定植率为10.3%,阴道和直肠GBS定植率分别为9.23%、10.13%,检出率分别为89.6%、98.4%,差异无统计学意义(P0.05)。GBS对青霉素类、头孢吡肟、万古霉素和氨苄西林的敏感度为100%。GBS阳性组与GBS阴性组在母儿结局如早产、剖宫产、胎膜早破、霉菌性阴道炎、宫内感染、胎儿窘迫、新生儿窒息、新生儿肺炎的发生率比较差异有统计学意义(χ2值分别为13.904、4.868、8.382、39.799、46.570、43.624、40.429、91.571,P0.05)。结论妊娠期妇女GBS感染可能会对母儿预后造成不良影响,临床上有必要进行常规GBS检测,并对GBS阳性菌株进行药敏试验,以便有效的进行干预治疗,以保证围产期母儿的健康。     

Late antenatal carriage of group B Streptococcus by New Zealand women

OBJECTIVES: To determine in New Zealand women the prevalence of group B Streptococcus (GBS) carriage late in pregnancy and to identify GBS colonisation risk factors, antibiotic susceptibility and serotype distribution. DESIGN: Prospective, observational study. SETTING: Community and hospital antenatal clinics in Wellington and Auckland during 1998-1999. SAMPLE: Convenience sample of 240 women between 35-37 weeks gestation. METHODS: Sociodemographic data, obstetric details and anogenital swabs were collected from each subject. Swabs were inoculated into selective media. GBS isolates underwent serotyping and antibiotic susceptibility testing. RESULTS: Two hundred and forty women (9% Maori, 11% Pacific) aged 15-41 years were recruited. Fifty-two (22%; 95% CI 17, 27) were colonised by GBS. Carriage was independently associated with younger age (59% < or = 30 years; adjusted OR 3.25; 95% CI 1.53, 6.95) and least social deprivation (57% NZ Dep 96 score +/- 3; adjusted OR 1.22; 95% CI 1.06,1.39). All GBS isolates were penicillin-susceptible, but resistance to clindamycin (15%) and erythromycin (7.5%) was detected and associated with serotype V strains. Predominant serotypes were: III (29%), Ia (21%), Ib (20%) and V (20%). CONCLUSIONS: Approximately 20% of New Zealand women carry GBS late in pregnancy, with young age a major risk factor. Increased risk in the socially advantaged, development of resistance to erythromycin and clindamycin, and emergence of new GBS serotypes are findings with important implications for prevention strategies requiring further confirmation.     

Serotype distribution and mother-to-baby transmission rate of <Emphasis Type="Italic">Streptococcus agalactiae</Emphasis> among expectant mothers in Kuwait

Introduction Streptococcus agalactiae, also known as Group B Streptococcus (GBS), is a formidable pathogen that is commonly responsible for early-onset and late-onset infections with high morbidity and mortality in the neonatal period. Since this organism is usually acquired via the mothers birth canal during labor, this study investigated the maternal carriage rate, mother-to-baby transmission rate, and the common GBS serotypes found among expectant mothers and their babies in Kuwait.Methods The setting was the Maternity Hospital, Kuwait. Low vaginal-anorectal swabs (LVRS) and urine specimens were collected from 847 pregnant women during labor. Ear and umbilical swabs from their new-born babies were also collected. Each specimen was cultured on selective Todd–Hewitt media. Isolates were identified and serotyped by established methods.Results Of the 847 mothers, 124 (14.6%) were colonized and 74 (8.7%) babies were colonized, mainly at the umbilicus. The 124 GBS-positive mothers gave birth to 44 babies that were colonized by GBS at one or both sites, which corresponds to a mother-to-baby transmission rate of (35.5%). A total of 193 isolates were serotyped. The majority of the GBS isolates belonged to serotypes III (47; 24.3%), V (42; 21.8%), Ia (25; 12.9%), II and VI (15; 7.8%) each, and VII (11; 5.7%). Only 4 (2.1%) and 1 (0.5%) isolates belonged to serotypes Ib and IV respectively. No isolate belonged to serotype VIII and 33 (17.1%) were non-typable (NT).     

Serotyping group B streptococci in a small community hospital: an analysis of distribution and site of isolation

OBJECTIVE: To determine the prevalence and site of isolation of different serotypes of group B streptococcus (GBS) colonization or infection at a small community hospital. METHODS: GBS isolates were obtained from a small community hospital and were then serotyped as la, Ib, II, III, IV, V or nontypeable. Hospital records were reviewed for patient sex, age and pregnancy status as well as the site of GBS isolation. RESULTS: GBS serotypes Ia, III and V were most common and accounted for over 60% of the total number of isolates. Serotype Ia was most prevalent in reproductive-age females, while serotypes V and III were most prevalent in non-reproductive-age females and males, respectively. Serotype la was most frequent in both pregnant and nonpregnant females. Serotype IV was more common in this study population than in those from other locations. CONCLUSIONS: The GBS serotype distribution in this small community did not differ significantly from distributions described in larger North American centers. A GBS vaccine designed against multiple serotypes would be protective for most of this population.     

Maternal group B streptococcal (GBS) genital tract colonization at term in women who have asymptomatic GBS bacteriuria

OBJECTIVE: To determine the rate of positive group B streptococcus (GBS) cultures at 35-37 weeks gestation in women who have first trimester asymptomatic GBS bacteriuria. METHODS: Pregnant women with asymptomatic first trimester GBS bacteriuria had genital cultures for GBS performed at 35-37 weeks gestational age. Serotyping was performed by the standard Lancefield capillary precipitin method. RESULTS: Fifty-three women with positive urine cultures had genital cultures performed at 35-37 weeks. Sixteen of the 53 (30.2%; 95% confidence interval: 18.4-44.3%) third trimester vaginal cultures were positive for GBS. Five of eight (63%) of the women with typable urine serotypes had the same typable serotype in the third trimester genital culture. CONCLUSION: Genital tract cultures at 35-37 weeks for GBS correlate poorly with first trimester asymptomatic GBS bacteriuria. Recommendations for GBS prophylaxis in labor in women who have first trimester asymptomatic GBS bacteriuria should be investigated further and reconsidered.     

The international infections in pregnancy study: group B streptococcal colonization in pregnant women.

BACKGROUND: Heavy colonization with group B streptococcus (GBS) has been associated with increased risk of preterm birth and neonatal sepsis; the burden of neonatal GBS disease varies geographically. To determine whether variation in heavy colonization and GBS serotypes could contribute to geographic differences in disease burden, we assessed the prevalence of heavy colonization and the distribution of serotypes in asymptomatic pregnant women in multiple countries. METHODS: Cervical, lower vaginal and urine samples were collected from women attending seven prenatal clinics in six countries. Light colonization was defined as GBS isolation from Lim broth only; heavy colonization was isolation from urine or sheep blood agar plates. Isolates were serotyped using capillary precipitation. RESULTS: GBS was present in 11.3% of 1308 participants (range 7.1-21.7%); 5.0% were heavily colonized (0.4-18.8%) and 6.4% were lightly colonized (2.9-8.0%). Serotypes III and V were most common (both 17.2%). Serotypes VII and VIII were found in one study center. CONCLUSIONS: The prevalence of heavy colonization and GBS serotypes varied significantly among our study centers. Whether this variation could in part explain geographic differences in neonatal morbidity and mortality is a hypothesis that needs further study.     

妊娠35～37周孕妇B族链球菌带菌与妊娠结局

目的了解妊娠晚期孕妇B族链球菌(GBS)带菌情况及GBS带菌对妊娠结局的影响。方法采用细菌培养法对221例妊娠35～37周孕妇产前阴道下1/3及肛周分泌物进行B族链球菌检测。将21例B族链球菌阳性孕妇作为GBS阳性组,按1∶2配比病例对照研究,42例B族链球菌阴性孕妇作为GBS阴性组,观察其妊娠结局。结果 221例孕妇B族链球菌阳性检出率为9.5%(21/221)。GBS阳性组胎儿窘迫和宫内感染发生率分别为47.6%和14.3%,GBS阴性组分别为7.1%和4.8%,两组比较,差异均有统计学意义(P<0.05)。GBS阳性组胎膜早破和早产发生率分别为28.6%和4.8%,GBS阴性组分别为28.5%和2.4%,两组比较,差异均无统计学意义(P>0.05)。GBS阳性组和阴性组新生儿感染率分别为14.3%和4.8%,两组比较,差异有统计学意义(P<0.05)。结论妊娠晚期孕妇B族链球菌带菌明显增加宫内感染、胎儿窘迫及新生儿感染的发生率,对妊娠结局造成不良的影响,应对孕晚期孕妇常规行GBS筛检。     

妊娠晚期孕妇B族链球菌带菌状况的检测及带菌对妊娠结局的影响

目的 探讨妊娠晚期孕妇B族链球菌带菌状况的检测方法及带菌对妊娠结局的影响.方法收集2008年12月-2009年6月在北京大学第一医院妇产科进行B族链球菌检测的孕妇617例,平均年龄为30.1岁,其中高龄孕妇(≥35岁)80例;经产妇41例,初产妇576例;对617例孕妇于孕35～37周取阴道下1/3分泌物及肛周分泌物,应用细菌培养及实时PCR两种方法进行B族链球菌检测,并观察其妊娠结局.结果 (1)B族链球菌阳性检出率:B族链球菌培养阳性21例(3.4%,21/617),实时PCR检测阳性57例(9.2%,57/617).21例B族链球菌培养阳性孕妇,实时PCR检测均为阳性;36例实时PCR检测B族链球菌阳性、而细菌培养阴性孕妇在进行扩增测序后证实,34例为B族链球菌阳性,2例阴性.(2)实时PCR检测B族链球菌的诊断价值:实时PCR检测B族链球菌的敏感度为100%(55/55),特异度为99.6%(560/562).(3)B族链球菌阳性的相关因素:B族链球菌阳性孕妇平均年龄为(30.4±3.6)岁,阴性孕妇平均年龄为(30.9±3.5)岁,两者年龄比较,差异无统计学意义(P>0.05).经产妇B族链球菌阳性率为7.3%(3/41),初产妇阳性率为9.4%(54/576),两者比较,差异无统计学意义(P>0.05).高龄孕妇(≥35岁)B族链球菌阳性率高于年龄<35岁孕妇的阳性率,但差异无统计学意义(P>0.05).流产≥3次孕妇的B族链球菌阳性率与流产<3次孕妇比较,差异也无统计学意义(P>0.05).(4)分娩方式:B族链球菌阳性孕妇的剖宫产率为54.4%(31/57),阴性孕妇的剖宫产率为44.6%(250/560),两者比较,差异无统计学意义(P>0.05).(5)产时情况:B族链球菌阳性孕妇的胎膜早破发生率为33.3%(19/57),阴性孕妇的胎膜早破发生率为25.0%(140/560),两者比较,差异无统计学意义(P>0.05).B族链球菌阳性孕妇的宫内感染发生率为15.8%(9/57),显著高于阴性孕妇宫内感染发生率[6.6%(37/560)],两者比较,差异有统计学意义(P<0.05).B族链球菌阳性孕妇产后出血发生率和胎儿窘迫发生率均显著高于阴性孕妇(P<0.05),而早产发生率、羊水污染发生率在B族链球菌阳性与阴性孕妇中比较,差异无统计学意义(P>0.05).(6)新生儿感染率:B族链球菌阳性孕妇所分娩的新生儿中,新生儿感染发生率为29.8%(17/57);阴性孕妇所分娩的新生儿中,新生儿感染率为13.2%(77/560),两者比较,差异有统计学意义(P<0.05).B族链球菌带菌孕妇的新生儿中,有1例发生了严重早发感染,经及时处理,结局良好.结论 妊娠晚期孕妇B族链球菌携带明显增加宫内感染及新生儿感染的发生率,对妊娠结局造成不良影响.实时PCR检测B族链球菌感染有较高的敏感度和特异度,有望成为妊娠晚期孕妇常规检测B族链球菌的一种方法.     

窒息早产儿最大长度序列脑干听觉诱发电位的变化及意义

目的 研究围产期窒息缺氧对早产儿脑干听觉功能的影响,分析能够早期反映脑干听觉功能变化的敏感指标以及最大长度序列脑干听觉诱发电位(maximum length sequence brainstem auditory evoked potential,MLS BAEP)是否较常规法对脑干听觉功能异常的检出具有优越性. 方法窒息早产儿组:胎龄29～33<'+6>"周有围产期窒息缺氧病史的早产儿51例.对照组:正常早产儿47例,正常足月儿38例.MLS BAEP检测时间分别为生后3～7 d、纠正胎龄37～42周、3个月.常规法声刺激速率为21次/s,MLS声刺激速率为91、227和455次/s,采用t检验比较组间Ⅰ、Ⅲ、Ⅴ波潜伏期和振幅,Ⅰ-Ⅲ、Ⅲ-Ⅴ、Ⅰ-Ⅴ峰间期的差异. 结果生后3～7 d,窒息早产儿较正常早产儿Ⅲ波、Ⅴ波潜伏期,Ⅰ-Ⅲ、Ⅲ-Ⅴ和Ⅰ-Ⅴ峰问期延长,Ⅴ波振幅降低(P<0.05).声刺激速率为455次/s时,窒息早产儿组Ⅲ波潜伏期为(6.64±0.58)ms,V波潜伏期为(10.57±0.93)ms Ⅰ-Ⅲ峰间期为(3.69±0.55)ms,Ⅲ-Ⅴ峰间期为(3.93±0.53)ms,Ⅰ-Ⅴ峰间期为(7.60±0.73)ms,明显低于正常早产儿.纠正胎龄足月时窒息早产儿组Ⅰ-Ⅲ峰间期已恢复正常,但Ⅴ波潜伏期、Ⅲ-Ⅴ和Ⅰ-Ⅴ峰间期仍相对延长且Ⅴ波振幅减低(P<0.01).在纠正年龄3个月时窒息早产儿组常规BAEP与足月儿组的差异已不明显,仅在较高声刺激速率时仍有部分参数异常. 结论围产期窒息缺氧可以对早产儿BAEP造成影响,但随早产儿生长发育有一定程度恢复.脑干听觉通路的近中枢部位对缺氧损伤易感,波形变化出现早,恢复慢.Ⅴ波潜伏期和振幅、Ⅲ-Ⅴ和Ⅰ-Ⅴ峰间期可作为判断早产儿缺氧损伤的早期敏感指标.MLS BAEP通过提高声刺激速率,可以提高诊断价值.