肺炎链球菌耐药性研究进展

肺炎链球菌是重要的致病菌,近年来肺炎链球菌对青霉素等多种药物的耐药性在全球普遍呈上升趋势。同时,分子生物学方法的应用使肺炎链球球菌耐药性的发生和传播机制得到了较全面的阐述。     

肺炎链球菌对β-内酰胺类及大环内酯类抗生素耐药基因的研究进展

近年来,肺炎链球菌对β-内酰胺类及大环内酯类抗生素的耐药率在逐渐上升,目前关于其耐药基因的研究已引起广泛关注,现就肺炎链球菌对β-内酰胺类及大环内酯类抗生素耐药基因的研究进展作一综述.     

长春地区猪链球菌对大环内酯和林克酰胺类耐药的分子机制研究

目的　分析长春地区猪链球菌耐大环内酯类和林克酰胺类的分子机制。方法　采用微量稀释法和双纸片扩散法分别测定相关抗生素的耐药谱和红霉素耐药型 ,并以猪链球菌的染色体DNA为模板 ,PCR扩增ermB基因和mefA/E基因 ,然后将其克隆到pMD18-T载体中 ,用双脱氧链末端终止法测定DNA序列后进行序列分析。结果　 2 2株猪链球菌的临床分离菌株均扩增出ermB基因 ,而未扩增出mefA/E基因 ;对四环素、环丙沙星和大环内酯和克林霉素有高的耐药率和耐药水平 ;红霉素的耐药型以CR型为主。同源性分析显示 ,ermB基因的差异为 36 %～ 10 0 % ,与GenBank中的肺炎链球菌、粪肠球菌等的erm基因有 98%～ 10 0 %的同源性。结论　长春地区猪链球菌对MLSB 的耐药是红霉素甲基化转移酶所介导的 ,以CR型为主的耐药 ,编码该类耐药的是ermB基因 ,并与人源及动物源性的耐药基因可能存在着广泛的交换。     

呼吸道感染肺炎链球菌分离株的耐药性分析

目的研究呼吸道感染患者肺炎链球菌分离株的耐药情况。方法通过细菌培养获得肺炎链球菌，对获得的肺炎链球菌进行药敏实验。结果呼吸道分离肺炎链球菌中青霉素耐药(PRSP)占39．3％，对头孢哌酮／舒巴坦、头孢克洛、头孢呋辛、头孢噻肟、头孢曲松、环丙沙星、左氧氟沙星、红霉素、克林霉素、复方新诺明、万古霉素、利福霉素的耐药率分别为39．3％，13．8％，36．6％，17．2％，35．9％，16．6％，40．0％，36．6％．51．7％，38．6％，60．0％，0和17．2％。结论吉林省肺炎链球菌对青霉素的耐药率已经处于较高水平，耐青霉素菌株对其他抗生素普遍耐药．已经发现对三代头孢菌素耐药菌株，未发现万古霉素耐药菌株。     

肺炎患儿肺炎链球菌的分离及耐药性分析

目的 调查肺炎患儿肺炎链球菌的分离及耐药性.方法 通过对415例肺炎患儿痰及咽拭子标本培养,分离SP,予以细菌鉴定和药敏的试验.结果 415例标本中共分离出肺炎链球菌96株（23.13%）,炎链球菌对青霉素的耐药率为41.67%.在检测的β-内酰胺类抗菌药物中,头孢噻肟与头孢曲松较为敏感,分别为66.66%、79.16%.对青霉素敏感和不敏感的肺炎链球菌其对头孢噻肟、头孢曲松、头孢呋辛、红霉素、阿奇霉素及克林霉素的敏感性也各不相同,P〈0.01.结论 肺炎儿童SP分离率高,SP对万古霉素、左氧氟沙星敏感性高,对头孢噻肟、头孢曲松、头孢呋辛及氯霉素比较敏感,对青霉素耐药率比较严重.     

2006～2007年南京地区肺炎链球菌耐药情况分析

目的 了解南京地区肺炎链球菌对常用抗菌药物的耐药性.方法 琼脂稀释法测定130株肺炎链球菌对14种抗菌药物最低抑菌浓度.结果 130株肺炎链球菌中,耐青霉素肺炎链球菌的检出率为51.5%;头孢呋辛、头孢噻肟、阿莫西林、头孢曲松的耐药率依次为69.2%、17.7%、6.2%和3.1%;四环素、红霉素、阿奇霉素和克林霉素耐药率分别为93.8%、92.3%、90.8%和89.2%;万古霉素、新喹诺酮类左氧氟沙星和莫西沙星、替加环素、利奈唑胺均敏感.结论 南京地区肺炎链球菌对青霉素、红霉素、阿奇霉素、克林霉素、四环素、头孢呋辛等抗生素耐药性高,应注意合理选择用药.     

肺炎支原体对大环内酯类抗生素耐药机制的研究近况

肺炎支原体是社区获得性肺炎的主要病原体。大环内酯类抗菌药物是治疗儿童肺炎支原体感染的首选药物。近年来我国耐大环内酯肺炎支原体比例有所下降,但仍处于高水平。耐药肺炎支原体感染造成患者发热时间、住院时间延长,并有更高的并发症发生率和抗生素治疗方案改变率,因此对肺炎支原体耐药机制的研究还需进一步深入。肺炎支原体对大环内酯类抗生素耐药机制主要与抗生素作用靶点突变、抗生素作用靶点修饰、药物主动外排、酶性失活有关。     

肺炎链球菌对红霉素的耐药表型及耐药基因

目的　研究肺炎链球菌对红霉素的耐药表型及耐药基因。方法　根据美国临床实验室标准化委员会标准使用微量肉汤稀释法 ,检测 192株肺炎链球菌对红霉素、克林霉素、青霉素、喹诺酮类抗菌药物的最低抑菌浓度 (MIC)。应用红霉素、克林霉素、螺旋霉素纸片行三纸片扩散法 ,检测 14 8株红霉素耐药肺炎链球菌的耐药表型。应用PCR检测 14 8株红霉素耐药肺炎链球菌携带的耐药基因。结果　肺炎链球菌对青霉素的耐药率 (中介率 耐药率 )为 4 2 7% ,对红霉素、克林霉素的耐药率分别为 77 6 %、6 6 7%。 14 8株红霉素耐药株中 ,耐药基因以ermB基因 (79 1% )为主 ,耐药表型以内在型耐药 (cMLS) (85 1% )为主。携带ermB基因的肺炎链球菌 ,74 4 %的菌株对红霉素的MIC值 >16 0 μg/ml;而携带mefA基因的肺炎链球菌对红霉素的MIC值在 0 5～ 4 0 μg/ml之间。 结论肺炎链球菌对红霉素的耐药率较高 ;耐药表型以cMLS为主 ,耐药基因以ermB介导的靶位改变多见。     

大环内酯类耐药肺炎链球菌及其临床意义

肺炎链球菌是社区获得性肺炎最重要的致病菌，同时也是引起中耳炎、鼻窦炎、脑膜炎和脓毒症的主要致病菌。红霉素及其他大环内酯类抗生素对肺炎链球菌具有良好的抗菌活性，并兼有抗非典型病原体(肺炎支原体、肺炎衣原体和军团菌等)活性，特别是新大环内酯类抗生素如克拉霉素和阿奇霉素等有很好的耐受性，又增强了对流感嗜血杆菌的抗菌活性，     

肺炎链球菌对红霉素的耐药性及耐药表型

目的 调查上海地区肺炎链球菌对红霉素，克林霉素的耐药率及红霉素耐药菌的耐药表型。方法 以琼脂稀释法测定345株肺炎链球菌对红霉素，克林霉素的最低抑菌浓度，以双纸片法测定红霉素耐药菌的耐药表型。结果 肺炎链球菌对红霉素及克林霉素及克林霉素的耐药率分别为53.0%（183/345）及49.6%(171/345)。对红霉素耐药菌中，内在型耐药（cMLS)占90.3%(159/176)，诱导型耐药（iMLS)占5.7%(10/176)，M型耐药占4.0%(7/176)。结论 上海地区肺炎链球菌对红霉素的耐药率高，其耐药表型以cMLS为主。     

Correlation between usage of macrolide antibiotic and resistance of Streptococcus pneumoniae clinic isolates from chongqing children's hospital

To investigate the reasons of growing resistance problem of Streptococcus pneumoniae against macrolide in Chongqing, a retrospective method was employed to measure the minimal inhibition concentrations (MIC) of macrolide antibiotic against 1,210 S. pneumoniae clinic isolates. The defined daily doses (DDDs) of macrolide antibiotic were calculated. Polymerase chain reaction (PCR) was used to determine the presence of the erythromycin‐resistant genes in 100 macrolide‐resistant S. pneumoniae isolates. A decrease in macrolide consumption, from 371,100 DDDs in 2002 to 182,500 DDDs in 2005 (51% reduction); however, the rate of erythromycin resistance in S. pneumoniae showed continued increase from 88.0% in 2002 to 96.0% in 2005. No linear correlation was observed between the decline in macrolide consumption and continued increase in resistant rate in S. pneumoniae. In 100 macrolide‐resistant S. pneumoniae isolates, 68 had both erm(B) and mef(A) genotypes, 10 only had the erm(B), 20 only had the mef(A). Co‐existences of ribosomal modification coded by erm(B) gene and efflux effects coded by mef(A) gene were the main resistance mechanism against macrolides and might be attributed to the high drug resistance of S. pneumoniae in Chongqing. Pediatr Pulmonol. 2009; 44:917–921. © 2009 Wiley‐Liss, Inc.     

Penicillin resistance in Streptococcus pneumoniae in Isparta

OBJECTIVE: The first case reports of infection with penicillin-resistant pneumococci were made in Australia in 1967 and South Africa in 1977. Since this time the increasing emergence of penicillin- resistant strains of Streptococcus pneumoniae have been a serious therapeutic problem. Therefore, the aim of the present study was to determine the penicillin resistance of S. pneumoniae strains isolated in the laboratory. The effect of procaine penicillin treatment against these strains was also investigated. METHODS: Sensitivity testing was done by disc diffusion method using oxacillin discs. Minimal inhibitory concentration (MIC) values were determined in tests with penicillin by the use of E-test (AB Biodisc, Solna, Sweden). Patients were treated with 2 x 800,000 U of i.m. procaine penicillin every 12 h for 10 days. RESULTS: Thirty-seven strains of S. pneumoniae were isolated from the sputa of adult patients who had pneumonia. Moderately resistant (0.12-1.00 microg/mL) and penicillin-sensitive (< or = 0.06 microg/mL) strains were identified in nine (24.3%) and 28 (75.7%) isolates, respectively. There were no high-level penicillin-resistant strains in the study. There was no therapeutic failure. CONCLUSION: These results suggest that procaine penicillin may still be useful in the empirical therapy of pneumococcal pneumonia.     

184例儿童感染肺炎链球菌的血清型分布及其耐药性分析

目的分析184例儿童感染肺炎链球菌的血清型分布及其耐药性情况。方法选取2014年1月至2017年12月我院呼吸道感染患儿2828例,进行痰液培养,分析病原菌检出情况,肺炎链球菌分布情况、血清分型以及对抗生素耐药性情况。结果2828例患儿的痰标本共检出674株病原菌(23.83%),其中肺炎链球菌184例,检出率为6.51%。年龄1个月~1岁患儿感染肺炎链球菌发生率为52.17%,明显高于1~3岁、3~6岁患儿的25.54%、22.28%(P<0.05);冬季患儿感染肺炎链球菌发生率为53.26%,明显高于春季、夏季、秋季的19.02%、13.05%、14.67%(P<0.05);184株肺炎链球菌共涉及11个血清型/群,主要分布于19F、19A、14型、9V、23F、6B、8型、7F、7A、其他等,另有11株未能分型。青霉素(脑膜炎)的不敏感率高达83.33%,明显高于青霉素(非脑膜炎)的63.24%(P<0.05);而头孢曲松对感染肺炎链球菌脑膜炎或非脑膜炎患儿的敏感率比较,无统计学意义(P>0.05)。患儿感染肺炎链球菌的青霉素(脑膜炎)、红霉素、四环素、复方新诺明、头孢克罗、克林霉素耐药检出率分别为72.91%、86.96%、89.13%、79.89%、80.43%、77.23%;而万古霉素、氯霉素、左氧氟沙星、氧氟沙星、莫西沙星、头孢曲松敏感率分别为100.00%、95.65%、98.38%、91.85%、92.94%、91.85%。结论儿童感染肺炎链球菌存在明显的年龄、季节、血清分布与耐药性差异,此研究结果对儿童肺炎抗感染治疗经验性抗生素选择有指导意义。     

国内耐药肺炎链球菌的流行现状

肺炎链球菌可引起细菌性肺炎、中耳炎和脑膜炎等疾病,是当今发达国家和发展中国家共有的一个重要病原.由于抗生素长期的过度使用,许多肺炎链球菌菌株能够同时耐受多种常用的抗生素,使得临床可应用的有效抗生素越来越少.耐药肺炎链球菌正在朝着超级细菌方向发展.这种现状值得我们关注并寻求近期和长期的解决方法.本文对国内肺炎链球菌耐...     

肺炎克雷伯菌体外耐药监测

目的 探讨肺炎克雷伯菌（KP）的分布、感染特点及其体外对抗生素的耐药情况。方法 采用纸片扩散法K-B法对武汉大学人民医院临床分离的130株KP进行耐药性检测，并用双纸片协同法初筛、确证法检测产超广谱β-内酰胺酶（ESBLs）菌。结果 130株KP主分布于呼吸内科，并以第二季度最多；对氨苄西林的耐药率高达95．31％，对第三代头孢菌素类抗生素的耐药率为41．27％～52．46％；最敏感抗生素为亚胺培南。产ESBLs肺炎克雷伯菌检出率为29．23％。结论 肺炎克雷伯菌对抗生素的耐药性日趋严重，临床实验室应常规检测其是否产ESBLs。     

Serotype distribution and antibiotic susceptibility of invasive and nasopharyngeal isolates of Streptococcus pneumoniae among children in rural Mozambique

Objective To describe and compare serotype distribution and antibiotic susceptibility of invasive and nasopharyngeal isolates of Streptococcus pneumoniae from children in rural Mozambique. Methods From August 2002 to July 2003, we prospectively obtained invasive pneumococcal isolates from children <15 years of age admitted to the paediatric ward of Manhiça District Hospital. During a cross‐sectional study of children <5 years of age with mild illnesses, attending the outpatient department of the hospital in March and April 2003, we collected nasopharyngeal isolates. Serotypes and antibiotic susceptibilities were determined using standardized methods. Results The two most common pneumococcal serotypes among invasive isolates were types 1 (40% of 88 isolates serotyped) and 5 (10%), but these types were rare among nasopharyngeal isolates. Compared with invasive isolates, nasopharyngeal isolates were more likely to be serotypes in the licensed seven‐valent conjugate vaccine (49%vs. 20%, P < 0.01), to have intermediate‐level penicillin resistance (52%vs. 14%, P < 0.01) and to be non‐susceptible to trimethoprim–sulfamethoxazole (61%vs. 45%, P < 0.01). Recent receipt of antibiotics or sulfadoxine/pyrimethamine were associated with carriage of antibiotic non‐susceptible isolates. Conclusions These data indicate that a pneumococcal conjugate vaccine containing serotypes 1 and 5 could substantially reduce pneumococcal invasive disease among young children in rural Mozambique. Carriage surveys can overestimate potential coverage of the seven‐valent pneumococcal conjugate vaccine in settings where serotypes 1 and 5 predominate.     

A comparative clinical study of pneumonia by penicillin-resistant and -sensitive Streptococcus pneumoniae in a community hospital

OBJECTIVE: This study aimed to determine the clinical difference of pneumonia between penicillin-resistant and penicillin-sensitive Streptococcus pneumoniae. METHODOLOGY: Forty-nine cases in 46 patients of pneumococcal pneumonia were studied from December 1992 to May 1997. There were 24 cases (in 22 patients) of penicillin-resistant pneumococci (PRSP) pneumonia which were compared with 25 cases (in 24 patients) with penicillin-sensitive pneumococci (PSSP). RESULTS: Both the mean age and the underlying disease states did not differ between the two groups. However, hospital-acquired pneumonia and previous use of antibiotics were observed in eight (33.3%) and 12 (50.0%) patients in PRSP compared with three (12.0%) and two (8.0%) in PSSP, respectively. The clinical efficacy rate and bacteriological eradication rates were 87.5 and 87.5% in PRSP compared with 87.5 and 87.0% in PSSP, respectively. Minimum inhibitory concentration (MIC) of antibiotics against 30 pneumococcal isolates was examined, and 10 strains ranged from 0.10-0.78 microg/mL and five strains were more than 1.56 microg/mL against penicillin G, while the MIC showed higher resistance to other antibiotics except for the carbapenems. Serotyping of the isolates by antiserum revealed differences in the predominant types PRSP (19F) and PSSP (6A,9V) [corrected]. CONCLUSIONS: We must care for not only community-acquired infection but also nosocomial transmission of PRSP pneumonia. Most patients with infections due to PRSP tended to have a milder illness with a good outcome (no patient died). As such it appears that empiric therapy for pneumococcal pneumonia does not require modification from what is recommended at present. However, in patients with infection due to highly resistant strains, and who are not responding to conventional therapy should have their treatment modified according to subsequent susceptibility testing.