Antimicrobial Susceptibility Trends of Streptococcus pneumoniae by Age Groups Over Recent 10 Years in a Single Hospital in South Korea

PurposeStreptococcus pneumoniae (S. pneumoniae) causes respiratory tract infections. Its non-vaccine serotypes and multidrug-resistant pneumococcal diseases have increased during the post-pneumococcal vaccination era. Therefore, it is important to understand the regional and age-related antimicrobial susceptibility of S. pneumoniae to select appropriate empirical antimicrobials.Materials and MethodsWe retrospectively studied trends in the antimicrobial resistance of S. pneumoniae to commonly prescribed antibiotics in patient groups of various ages at a single teaching hospital in Jeju Island from 2009 to 2018.ResultsIn total, 1460 S. pneumoniae isolates were obtained during the study period. The overall antimicrobial resistance rates of S. pneumoniae to penicillin, erythromycin, ceftriaxone, levofloxacin, and vancomycin were 16.2%, 84.7%, 25.9%, 3.3%, and 0.0%, respectively, and the MDR rate was 6.7%. Erythromycin and ceftriaxone resistance rates increased by years; however, they were significantly reduced in adult groups. Levofloxacin resistance and MDR rates were also higher in adult groups. Overall, the MDR rate significantly increased during the recent 10 years, as well as in patients with a history of hospitalization within 90 days [odds ratio (OR)=3.58, 95% confidence interval (CI)=1.91–6.71] and sinusitis (OR=4.98, 95% CI=2.07–11.96).ConclusionErythromycin and ceftriaxone resistance rates and the MDR rate of S. pneumoniae significantly increased during the recent 10 years; the trends in individual antimicrobial resistance rates significantly differed between the age groups. This study indicates the need for caution when using ceftriaxone as an empirical antimicrobial against pneumococcal infections.     

NAF与EGCG联合应用对变异链球菌的作用研究

摘要：目的：研究氟化钠（Sodium fluoride,NAF）与表没食子儿茶素没食子酸酯（Epigallocatechingallate,EGCG）联合应用对变异链球菌的影响。方法：采用微量稀释法分别测量NAF与EGCG对变异链球菌的最小细菌抑制浓度MIC值,采用棋盘微量稀释法测量NAF与EGCG联合作用于变异链球菌的MIC值,并计算FIC指数。结果：NAF单独作用于变异链球菌MIC值为100ppm, EGCG单独作用于变异链球菌的MIC值为500ppm,NAF与EGCG联合应用时MIC值分别为25ppm和62.5ppm,FIC指数为 0.375,FIC指数小于0.5。结论：NAF与EGCG联合应用具有协同抑制变异链球菌的作用。     

The use of dried cerebrospinal fluid filter paper spots as a substrate for PCR diagnosis of the aetiology of bacterial meningitis in the Lao PDR

We investigated whether dried cerebrospinal fluid (CSF) conserved on filter paper can be used as a substrate for accurate PCR diagnosis of important causes of bacterial meningitis in the Lao PDR. Using mock CSF, we investigated and optimized filter paper varieties, paper punch sizes, elution volumes and quantities of DNA template to achieve sensitive and reliable detection of bacterial DNA from filter paper specimens. FTA Elute Micro CardTM (Whatman, Maidstone, UK) was the most sensitive, consistent and practical variety of filter paper. Following optimization, the lower limit of detection for Streptococcus pneumoniae from dried mock CSF spots was 14 genomic equivalents (GE)/μL (interquartile range 5.5 GE/μL) or 230 (IQR 65) colony forming units/mL. A prospective clinical evaluation for S. pneumoniae, S. suis and Neisseria meningitidis was performed. Culture and PCR performed on fresh liquid CSF from patients admitted with a clinical diagnosis of meningitis (n = 73) were compared with results derived from dried CSF spots. Four of five fresh PCR-positive CSF samples also tested PCR positive from dried CSF spots, with one patient under the limit of detection. In a retrospective study of S. pneumoniae samples (n = 20), the median (IQR; range) CSF S. pneumoniae bacterial load was 1.1 × 10⁴ GE/μL (1.2 × 10⁵; 1 to ×.1 × 10⁶ DNA GE/μL). Utilizing the optimized methodology, we estimate an extrapolated sensitivity of 90%, based on the range of CSF genome counts found in Laos. Dried CSF filter paper spots could potentially help us to better understand the epidemiology of bacterial meningitis in resource-poor settings and guide empirical treatments and vaccination policies.     

黄芩苷对变异链球菌UA159体外的抑制作用

目的探讨黄芩苷对变异链球菌国际标准株UA159的体外抑制作用。方法采用液体倍比稀释法结合酶标仪测OD600值测定黄芩苷对变异链球菌UA159的最低抑菌浓度(minimum inhibitory concentration,MIC)。利用酶标仪测定不同浓度的黄芩苷药液中变异链球菌UA159的OD600值,绘制生长曲线;计算黏附率及黏附抑制率;用结晶紫定量法测定黄芩苷对变异链球菌UA159生物膜形成的影响;用扫描电镜观察黄芩苷对变异链球菌UA159细菌总量的影响。结果黄芩苷对变异链球菌UA159最低抑菌浓度为12 mg/mL;随着黄芩苷药液浓度的增加,变异链球菌UA159生长速度缓慢,并且其黏附率下降,黏附抑制率增加(P<0.05)。结晶紫定量法结果显示,与菌液组相比,0、6、12 h时加入黄芩苷药液变异链球菌UA159生物膜形成量显著降低(P<0.001)。扫描电子显微镜下,0、6、12 h时加入黄芩苷后细菌总量均明显下降。结论黄芩苷能够抑制体外变异链球菌UA159的生长繁殖;同时其对变异链球菌UA159的黏附、生物膜形成均有抑制作用。     

孕晚期产妇生殖道B族链球菌感染与胎膜早破及新生儿结局的相关性

目的:探讨孕晚期产妇生殖道B族链球菌(group B Streptococcus,GBS)感染与胎膜早破及新生儿结局的相关性。方法:搜集2017年5月至2019年8月首都医科大学附属北京世纪坛医院产科门诊的2100例孕妇,选取其中122例孕晚期胎膜早破产妇作为观察组,另选取120例同期健康孕晚期产妇作为健康对照组,比较两组GBS感染率,依据观察组患者是否合并GBS感染,将其分为GBS阴性组与GBS阳性组,采用单因素和多因素logistic回归分析影响胎膜早破孕妇GBS感染的危险因素,观察不同组别不良妊娠情况及新生儿结局。结果:健康对照组GBS感染率显著低于观察组(P<0.05);两组孕妇胎位异常、双胎或多胎妊娠和巨大儿发生率比较差异具有统计学意义(P<0.05);经多因素logistic回归模型分析结果显示胎位异常、双胎或多胎妊娠和巨大儿为影响胎膜早破孕妇GBS感染的危险因素(P<0.05)。GBS阴性组早产、产后出血和宫内感染率均显著低于GBS阳性组(P<0.05);GBS阳性组新生儿窒息和新生儿肺炎感染发生率均高于GBS阴性组(P<0.05);两组新生儿感染率比较,差异无统计学意义(P>0.05)。结论:胎位异常、双胎或多胎妊娠和巨大儿均可影响孕晚期胎膜早破产妇GBS感染,GBS感染可致新生儿窒息、新生儿感染和新生儿肺炎的发生,同时引起早产、产后出血和宫内感染等不良妊娠结局的发生。临床需要对孕晚期产妇生殖道GBS感染进行及时监测和处理,以降低其不良母婴结局的发生率。     

儿童侵袭性肺炎链球菌病35例临床特征和分离株耐药性分析

目的对厦门市儿童侵袭性肺炎链球菌病(IPD)的临床资料进行调查研究,分析儿童IPD的临床特征和细菌耐药性并指导临床诊治。方法回顾性分析2015年2月—2019年1月厦门大学附属妇女儿童医院收治IPD患儿的临床资料,包括人口学特征、临床表现和实验室检查。结果35例IPD患儿中,肺炎链球菌血流感染31例,肺炎链球菌脑膜炎4例;婴幼儿(<3岁)26例,夏季发病率低。所有患儿均出现高热,部分出现咳嗽、贫血。所有患儿C反应蛋白(CRP)增高,绝大部分患儿白细胞(WBC)、降钙素原(PCT)升高,部分患儿胆汁酸(TBA)、乳酸脱氢酶(LDH)、羟丁酸脱氢酶(HBDH)、肌酸激酶(CK)升高。侵袭性肺炎链球菌对利奈唑胺、万古霉素100%敏感;对阿莫西林较敏感;对克林霉素和红霉素100%耐药;脑膜炎者分离的肺炎链球菌对青霉素、头孢噻肟及头孢吡肟的耐药率明显高于血流感染者。治疗以阿莫西林-克拉维酸钾或第三代头孢菌素为主,肺炎链球菌性脑膜炎以头孢曲松联合万古霉素抗感染。结论IPD在婴幼儿中最常见,临床表现为高热等,常见的并发症为肺炎、贫血,伴有WBC、CRP及PCT升高。肺炎链球菌血流感染者分离的64.7%肺炎链球菌对青霉素敏感,肺炎链球菌脑膜炎患者分离的肺炎链球菌对青霉素完全耐药。抗生素的使用应合理、规范,药敏试验结果是重要的参考依据。     

hBD2对SP感染的A549细胞凋亡的影响

目的 观察人β-防御素2(hBD2)对肺炎链球菌(SP)感染人肺腺癌细胞(A549)细胞凋亡的影响。方法 建立SP感染A549细胞模型,hBD2以10、20和30ng/mL的浓度梯度干预该模型,观察细胞形态变化,CCK-8法检测细胞活力,qRT-PCR检测细胞Bax、Bcl-2及caspase-3mRNA表达,免疫细胞化学法检测细胞Bax、Bcl-2蛋白的表达。结果 SP感染引起A549细胞皱缩、空泡化,hBD2一定程度上保护细胞活力,抑制Bax表达,上调Bcl-2的表达。结论 hBD2对SP感染的A549细胞凋亡具有保护作用。     

202株肺炎链球菌感染的临床分布及耐药性分析

目的调查大庆某医院临床分离的202株肺炎链球菌的临床分布特征及耐药状况,为临床合理用药提供依据。方法对2014年1月—2018年12月期间大庆某医院分离的202株肺炎链球菌进行回顾性分析。结果202株肺炎链球菌主要分离自呼吸道标本(痰61.4%、咽拭子20.3%)及血液标本(14.9%);感染者以儿童及中老年人为主(87.6%),患者主要来源于ICU(16.8%)、呼吸内科(15.3%)、耳鼻喉科(12.4%)及儿科(11.9%)。肺炎链球菌对红霉素(99.3%)、四环素(91.3%)、复方磺胺甲噁唑(74.0%)耐药性较严重,青霉素的耐药率为37.1%,对三代头孢菌素(头孢曲松、头孢噻肟)、氯霉素、氟喹诺酮类及厄他培南较敏感,万古霉素和利奈唑胺全部敏感。结论肺炎链球菌以呼吸系统感染为主,感染人群以儿童及中老年人多见。肺炎链球菌对四环素、红霉素及复方磺胺甲噁唑耐药严重,临床应根据药敏结果合理使用抗菌药物治疗。