本文選題：A族乙型溶血性鏈球菌 + 耐藥性��； 參考：《重慶醫(yī)科大學(xué)》2009年碩士論文

【摘要】： 研究背景A族乙型溶血性鏈球菌(group A streptococcus pyogens,GAS)是鏈球菌中致病性較強(qiáng)的一種細(xì)菌,是急性呼吸道感染尤其是上呼吸道感染的重要致病原,可以引起急性扁桃體炎、猩紅熱和膿皰瘡,也可引起嚴(yán)重的侵襲性感染如敗血癥、壞死性筋膜炎和鏈球菌中毒休克綜合征。然而,隨著大環(huán)內(nèi)酯類(lèi)抗生素的廣泛使用,近十年來(lái)GAS對(duì)大環(huán)內(nèi)酯類(lèi)抗生素的耐藥已經(jīng)成為全球性關(guān)注的問(wèn)題,細(xì)菌耐藥性的增長(zhǎng)已經(jīng)成為臨床治療中的棘手問(wèn)題。 M蛋白是GAS的主要致病因子,由emm基因編碼。M蛋白抗原變異是M分型的基礎(chǔ),到目前為止,根據(jù)M蛋白抗原特異性可將GAS分為100多個(gè)型別,不同的型別其致病性不同,部分菌株感染可引起人類(lèi)嚴(yán)重并發(fā)癥如風(fēng)濕熱/風(fēng)濕性瓣膜性心臟病(RF/RHD)及急性腎小球腎炎等,因此,GAS分型對(duì)流行病學(xué)研究有重要意義。然而,GAS對(duì)大環(huán)內(nèi)酯類(lèi)抗生素的耐藥性及分子流行病學(xué)的大規(guī)模研究在國(guó)內(nèi)報(bào)道甚少,而重慶地區(qū)尚缺乏兒童GAS分離株耐藥性和分子流行病學(xué)大規(guī)模調(diào)查研究。 目的了解重慶地區(qū)GAS耐藥特點(diǎn);了解重慶地區(qū)GAS的emm基因分布特點(diǎn);分析重慶地區(qū)emm基因的主導(dǎo)型和感染性GAS的emm基因與疾病的關(guān)系。 方法收集我院住院患兒正常無(wú)菌部位血液、膿液、胸水標(biāo)本及我院門(mén)診患兒咽部、皮損部標(biāo)本及健康兒童咽部咽拭子標(biāo)本進(jìn)行培養(yǎng)、分離、鑒定A族乙型溶血性鏈球菌。微量肉湯稀釋法檢測(cè)A族乙型溶血性鏈球菌對(duì)8種抗生素的敏感性。聚合酶鏈反應(yīng)(PCR)擴(kuò)增并進(jìn)行測(cè)序從而對(duì)emm基因進(jìn)行分型確定emm基因的型別。 結(jié)果 (一)感染性GAS菌株組成 85株非侵襲性感染GAS菌株,急性扁桃體炎菌株為77株;猩紅熱為7株;膿皰瘡的菌株為1株。5株侵襲性感染GAS菌株,2株為血培養(yǎng)分離株;2株為腹股溝膿腫的膿液培養(yǎng)分離株;1株為肺炎的胸腔積液培養(yǎng)分離株。 (二) GAS菌株對(duì)8種抗菌素的敏感性試驗(yàn)結(jié)果 1、85株非侵襲性感染GAS菌株對(duì)抗菌藥的敏感性試驗(yàn)結(jié)果85株非侵襲性感染GAS菌株對(duì)大環(huán)內(nèi)酯類(lèi)抗生素和克林霉素的耐藥率在91.67%-97.62%;對(duì)四環(huán)素的耐藥+中介為75%;對(duì)青霉素和頭孢菌素類(lèi)及左氧氟沙星的敏感率均高達(dá)100%,未檢測(cè)到耐青霉素、頭孢菌素類(lèi)抗生素GAS菌株。 2、5株侵襲性感染GAS菌株對(duì)抗菌藥的敏感性試驗(yàn)結(jié)果5株侵襲性GAS菌株對(duì)大環(huán)內(nèi)酯類(lèi)抗生素如紅霉素、克拉霉素以及克林霉素的耐藥率均高達(dá)100%,對(duì)新一代的大環(huán)內(nèi)酯類(lèi)藥如阿奇霉素的耐藥率也高達(dá)80%;對(duì)四環(huán)素耐藥+中介為80%;而對(duì)于青霉素、頭孢呋辛和左氧氟沙星的敏感率仍為100%。 3、95株健康兒童攜帶GAS菌株對(duì)抗菌藥的敏感性試驗(yàn)結(jié)果95株健康兒童攜帶GAS菌株對(duì)大環(huán)內(nèi)酯類(lèi)抗生素的耐藥率在94.74%-96.84%;對(duì)四環(huán)素耐藥+中介為86.31%;對(duì)青霉素、頭孢呋辛和左氧氟沙星的敏感率均高達(dá)100%。 (三)emm基因分型結(jié)果 1、83株非侵襲性感染GAS菌株的emm基因分型結(jié)果83株非侵襲性感染GAS菌株中,最常見(jiàn)的型別為emm12.0,為52株,占62.65%;其次是emm1.0,為11株,占13.25%;再次是emm22.0,為8株,占9.64%;emm6.5和emm12.43均為2株,占2.41%;而emm63.0、emmSTG485.0、emmST1815.0、emm3.1、emm80.0、emm86.1、emm75.0和emm102.2均為1株,僅占1.20%。 2、5株侵襲性感染GAS菌株的emm基因分型結(jié)果5株侵襲性感染GAS菌株中3株為emm12.0;1株為emm1.0;1株無(wú)法分型。 3、84株健康兒童攜帶GAS菌株的emm基因分型結(jié)果84株健康兒童攜帶GAS菌株中,最常見(jiàn)的型別為emm12.0,為54株,占64.29%;其次是emm22.0,為13株,占15.48%;再次是emm6.0,為6株,占7.14%;emm1.0和emm4.0均為5株,占5.95%;而emm12.21為1株,僅占1.19%。 (四)來(lái)源于各病種的GAS與emm基因分型的對(duì)應(yīng)關(guān)系結(jié)果檢測(cè)扁桃體炎GAS菌株75株,以emm12.0所占比例最大為62.67%,然后依次是emm1.0(12.00%),emm22.0(10.67%)等。膿皰瘡GAS菌株1株,為emm75。猩紅熱GAS菌株7株,其中5株為emm12.0,2株為emm1.0。敗血癥GAS菌株2株為emm12.0和emm1.0;腹股溝膿腫GAS菌株2株為emm12.0和無(wú)法分型;肺炎GAS菌株1株為emm12.0。 結(jié)論 (1)重慶地區(qū)兒童GAS菌株對(duì)大環(huán)內(nèi)酯類(lèi)抗生素表現(xiàn)出嚴(yán)重的耐藥,而對(duì)青霉素和頭孢菌素仍然保持高度敏感,故臨床推薦首選青霉素和頭孢菌素類(lèi)(頭孢Ⅰ、Ⅱ代)抗生素治療GAS疾病。 (2)重慶地區(qū)兒童感染性GAS菌株emm基因以emm12.0為主導(dǎo)型,其次為emm1.0、emm22.0等;健康兒童攜帶GAS菌株emm基因也以emm12.0為主導(dǎo)型,其次為emm22.0、emm6.0、emm1.0和emm4.0等。為此可進(jìn)一步為疫苗的研究提供依據(jù)。
[Abstract]:Background A Streptococcus (group A Streptococcus pyogens, GAS) is a highly pathogenic bacterium in Streptococcus. It is an important pathogen of acute respiratory infection, especially upper respiratory tract infection. It can cause acute tonsillitis, scarlet fever and pemphigus, and can also cause severe invasive infection such as sepsis and necrosis. Sexual fasciitis and streptococcal shock syndrome. However, with the widespread use of macrolide antibiotics, the resistance of GAS to macrolide antibiotics has become a global concern over the past ten years, and the growth of bacterial resistance has become a thorny problem in clinical treatment.
M protein is the main pathogenic factor of GAS. The mutation of the.M protein antigen of the emm gene is the basis of the M typing. So far, GAS can be divided into more than 100 types according to the specificity of the M protein antigen, and the pathogenicity of different types is different. Some strains of infection can cause severe and rheumatic fever / rheumatic heart disease (RF/RHD). As well as acute glomerulonephritis, GAS typing is of great significance for epidemiological studies. However, large scale studies on the drug resistance and molecular epidemiology of macrolide antibiotics in GAS are rarely reported in China, but there is still a lack of large-scale investigation on drug resistance and molecular epidemiology of GAS isolates in children in Chongqing.
Objective to understand the characteristics of GAS resistance in Chongqing and to understand the emm gene distribution of GAS in Chongqing area, and to analyze the relationship between the dominant type of emm gene in Chongqing and the emm gene of infectious GAS and the disease.
Methods the blood of normal aseptic parts of the hospital in our hospital, the specimens of pus, chest water and the pharynx of the outpatient of our hospital, the specimen of the skin lesion and the pharynx swab of the healthy children were cultured, separated and identified, and the A group B hemolytic streptococcus was identified. The sensitivity of the 8 antibiotics was detected by the micro broth dilution method for the detection of the sensitivity of the A group of hemolytic streptococcus. Enzyme chain reaction (PCR) was amplified and sequenced, and the emm gene was typed to determine the type of emm gene.
Result
(1) the composition of infectious GAS strains
85 strains of non invasive infection GAS, 77 strains of acute tonsillitis, 7 strains of scarlet fever, 1 strains of.5 strain GAS, 2 strains of blood culture, 2 strains of abscess in the abscess of the groin, and 1 for pneumonic pleural effusion.
(two) sensitivity test of GAS strain to 8 antibiotics.
Sensitivity tests of 1,85 strains of non invasive infection GAS strains against bacteria, the resistance rate of 85 strains of non invasive GAS strains to macrolide antibiotics and clindamycin was 91.67%-97.62%, the resistance to tetracycline was 75%, and the susceptibility to penicillin and cephalosporins and levofloxacin was up to 100%, and the resistance was not detected. Penicillin, cephalosporins GAS strain.
Susceptibility test of 2,5 strain GAS strains against bacteria, 5 invasive GAS strains were resistant to macrolides, such as erythromycin, clarithromycin and clindamycin, as high as 100%, and 80% for new generation of macrolides, such as azithromycin, and 80% for tetracycline resistance + mediator; The sensitivity rate of penicillin, cefuroxime and levofloxacin was still 100%.
The sensitivity test of 3,95 strains of healthy children carrying GAS strains against bacteria drug results, the resistance rate of 95 healthy children with GAS strains to macrolide antibiotics was 94.74%-96.84%, and the resistance to tetracycline was 86.31%, and the susceptibility to penicillin, cefuroxime and levofloxacin were all up to 100%.
(three) the results of EMM genotyping
The EMM genotyping results of non invasive GAS strain of 1,83 strain 83 strains of non invasive GAS strains, the most common type was emm12.0, 52, 62.65%, followed by emm1.0, 11, 13.25%, emm22.0, 8, 9.64%, emm6.5 and emm12.43, 2.41%, and emm63.0, emmSTG485.0, emmST1815.0, emmST1815.0, 2.41% Mm86.1, emm75.0 and emm102.2 were 1, accounting for only 1.20%..
The results of EMM genotyping of GAS strain infected with 2,5 strain showed that 3 of the 5 strains of GAS infected with GAS were emm12.0, 1 were emm1.0, and 1 strains could not be classified.
The EMM genotyping of GAS strains in healthy children of 3,84 strain 84 healthy children carried GAS strains, the most common type was emm12.0, 54, 64.29%, followed by emm22.0, 13, 15.48%, emm6.0, 6, 7.14%, emm1.0 and emm4.0, 5.95%, and 1, 1, only 1.19%..
(four) the corresponding relationship between GAS and emm genotyping from each disease species detected 75 strains of GAS strain of tonsillitis, the largest proportion of emm12.0 was 62.67%, followed by emm1.0 (12%), emm22.0 (10.67%), GAS strain 1 strains of pustular sore, 7 strains of emm75. scarlet fever GAS strain, 5 of which were emm1.0. septicemia GAS strain 2 The strains were emm12.0 and emm1.0; 2 strains of GAS of the inguinal abscess were emm12.0 and incapable of classification; 1 strains of pneumonia GAS strain were emm12.0..
conclusion
(1) the GAS strain of children in Chongqing region showed severe resistance to macrolide antibiotics and remained highly sensitive to penicillin and cephalosporins. Therefore, the first choice of penicillin and cephalosporins (cephalosporin I, II) antibiotics was the first choice for the treatment of GAS disease.
(2) the emm gene of infectious GAS strain of children in Chongqing area was guided by emm12.0, followed by emm1.0, emm22.0, etc. The emm gene of GAS strain in healthy children was also guided by emm12.0, followed by emm22.0, emm6.0, emm1.0 and emm4.0, and so on, which could provide the basis for the research of vaccine.
【學(xué)位授予單位】：重慶醫(yī)科大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2009
【分類(lèi)號(hào)】：R446.5;R450;R181.3

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 戰(zhàn)亞惠;2007-2011年長(zhǎng)春市猩紅熱流行特征分析[D];吉林大學(xué);2012年

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本文編號(hào)：1904934