2012—2015年1380株肝移植术后感染病原菌的分布及耐药性分析

目的了解江苏省人民医院肝移植术后感染病原菌的分布及耐药性,为临床合理用药提供参考。方法对2012年1月—2015年1月江苏省人民医院肝移植术后感染病原菌的分布及耐药性进行统计分析。结果共分离出病原菌1 380株,主要来源于痰液标本。病原菌分布以革兰阴性菌为主,占69.57%,革兰阳性菌和真菌分别占20.07%、10.36%;其中革兰阴性菌以鲍曼不动杆菌、肺炎克雷伯菌为主,革兰阳性菌以溶血葡萄球菌为主;革兰阴性菌对美罗培南、阿米卡星、亚胺培南较为敏感,耐药率均低于30%,对头孢曲松、氨曲南等的耐药率均较高;革兰阳性菌对万古霉素、利奈唑胺、替考拉宁较为敏感,耐药率均低于20%,对氨苄西林、诺氟沙星等耐药率均较高。结论肝移植术后感染病原菌的构成主要是鲍曼不动杆菌、肺炎克雷伯菌和溶血葡萄球菌,临床选择抗菌药物时建议选用病原菌表现较低耐药性的美罗培南、阿米卡星、万古霉素、利奈唑胺等药物。     

Effect of sodium mercaptoacetic acid on different antimicrobial disks in the sodium mercaptoacetic acid double disk synergy test for detection of IMP-1 metallo-β-lactamase-producing Pseudomonas aeruginosa isolates in Japan

We determined the optimal antimicrobial in the sodium mercaptoacetic acid double disk synergy test (SMA-DDST) for the detection of IMP-1-producing Pseudomonas aeruginosa isolates in Japan and evaluated the performance of the test.Fifty-four P. aeruginosa clinical isolates were tested, including 39 IMP-1 producers and 15 non-metallo-β-lactamase (MBL)-producing carbapenem- and ceftazidime (CAZ)-resistant isolates. The SMA-DDST was performed with CAZ, cefepime (CFPM), imipenem (IPM), meropenem (MEPM), doripenem (DRPM), or biapenem (BIPM)-containing disks. The sensitivity of the SMA-DDST with CAZ, CFPM, IPM, MEPM, DRPM, and BIPM was 39/39 (100%), 36/39 (92%), 18/39 (46%), 8/39 (21%), 19/39 (49%), and 36/39 (92%), respectively. The specificity was 15/15 (100%) for all SMA-DDSTs. This suggests that the isolates may have a resistance mechanism other than MBL production for IPM, MEPM, or DRPM. Since the CAZ resistance mechanism in P. aeruginosa is the same as that of CFPM, but differs from that of carbapenems, we conclude that combining CAZ with BIPM SMA-DDSTs can prevent any failure in the detection of IMP-1-producing P. aeruginosa.     

不同条件下CIM试验检测耐碳青霉烯类肠杆菌科细菌的评价

目的评估不同底物、不同孵育时间下碳青霉烯类抑制法(CIM)对肠杆菌科细菌碳青霉烯酶表型筛选能力的差异。方法分别用亚胺培南、美罗培南、厄他培南作为指示底物对120株耐碳青霉烯类肠杆菌科细菌(CRE)进行CIM试验,再以美罗培南为指示底物,分别孵育0.5、1、2、4h进行CIM试验,并采用PCR及测序技术检测菌株是否携带碳青霉烯酶相关基因。结果碳青霉烯酶耐药基因PCR检测结果显示,120株CRE中,阳性93株,阴性27株。以亚胺培南作为底物,阳性95株,阴性25株;以美罗培南作为底物,阳性87株,阴性33株;以厄他培南作为底物,阳性68株,阴性52株。与PCR结果相比,三者的灵敏度分别是98.9%(92/93),90.3%(84/93),69.9%(65/93),差异有统计学意义(χ~2=18.43,P<0.01);三者的特异度均为88.9%(24/27)。3种底物的一致率分别为96.7%,90.0%,74.2%,Kappa值分别是0.90,0.73,0.44。在4个不同孵育时间下,灵敏度分别为46.2%(43/93)、58.1%(54/93)、90.3%(84/93)和90.3%(84/93),孵育2h和0.5、1h结果相比差异有统计学意义(χ~2=27.31,P<0.05)。结论亚胺培南、美罗培南CIM试验灵敏度和一致率均高于厄他培南,可作为合适的底物,同时2h为最佳孵育时间。     

Klebsiella pneumoniae invasion syndrome: a case of liver abscess combined with lung abscess,endophthalmitis, and brain abscess

Klebsiella pneumoniae invasion syndrome (KPIS) is a critical multi-site infection that is usually caused by highly virulent Klebsiella pneumonia. It is relatively common in Asian patients with diabetes and leads to sepsis, which has a high mortality rate. We report the case of a man in his early 40s who presented to the hospital with blurred vision in his left eye of 7 days’ duration and fever of 1 day’s duration. After a complete examination, he was diagnosed with KPIS on the basis of his liver abscessation, lung abscessation, endophthalmitis of the left eye and brain abscessation. After needle puncture and drainage of the left eye and liver abscess and anti-bacterial treatment with meropenem, the patient recovered well. When KPIS is suspected, attention should be paid to the sites of infection and the selection of the most appropriate antibiotics, but the most important aim should be to drain the lesions in a timely manner to improve the patient’s prognosis.     

Combination therapy for carbapenem-resistant Gram-negative bacteria

The emergence of resistant to carbapenems Gram-negative bacteria (CR GNB) has severely challenged antimicrobial therapy. Many CR GNB isolates are only susceptible to polymyxins; however, therapy with polymyxins and other potentially active antibiotics presents some drawbacks, which have discouraged their use in monotherapy. In this context, along with strong pre-clinical evidence of benefit in combining antimicrobials against CR GNB, the clinical use of combination therapy has been raised as an interesting strategy to overcome these potential limitations of a single agent. Polymyxins, tigecycline and even carbapenems are usually the cornerstone agents in combination schemes. Optimization of the probability to attain the pharmacokinetic/pharmacodynamic targets by both cornerstone drug and adjuvant drug is of paramount importance to achieve better clinical and microbiological outcomes. Clinical evidence of the major drugs utilized in combination schemes and how they should be prescribed considering pharmacokinetic/pharmacodynamic characteristics against CR GNB will be reviewed in this article.     

美罗培南治疗中、重度细菌感染79例

目的观察美罗培南治疗中、重度细菌感染的有效性。方法采用随机对照、平行试验设计，对重症监护病房（ICU）158例中、重度细菌感染患者给予美罗培南治疗并观察临床疗效。结果美罗培南组79例，临床有效率为83．5％；亚胺培南组79例，临床有效率为84．8％。结论美罗培南治疗各种中、重度细菌感染的疗效与亚胺培南相似。     

兔玻璃体腔注射美罗培南治疗细菌性眼内炎

目的评价兔玻璃体腔注射国产美罗培南对敏感菌引起的眼内炎的疗效。方法选取健康成年日本大耳白兔24只，随机分为Ⅰ、Ⅱ两组，每组12只，分别玻璃体腔内接种金黄色葡萄球菌和绿脓杆菌建立相应的眼内炎模型。待出现典型眼内炎体征时，Ⅰ组和Ⅱ组再随机分为A、B组和C、D组。B、D组玻璃体腔均注射美罗培南1．25mg，A、C组分别注射万古霉素1．0mg和复达欣2．0mg作为对照。通过临床炎症评分、细菌培养阳性率、组织学检查病理评分等指标评估药物疗效。结果在两种眼内炎模型中，美罗培南用药后临床炎症评分均有显著下降，用药前后相比有统计学差异，但与万古霉素、复达欣相比无统计学差异；美罗培南用药后细菌培养阳性率在金黄色葡萄球菌和绿脓杆菌眼内炎模型中分别为0和16．7％，均低于万古霉素和复达欣，与万古霉素相比差异有统计学意义；用药2周后组织学检查显示绝大多数标本视网膜组织结构基本完整，层间有不同程度变性和坏死伴炎症细胞浸润，美罗培南与万古霉素、复达欣相比其视网膜病理评分均无统计学差异。结论兔玻璃体腔注射美罗培南治疗敏感金黄色葡萄球菌和绿脓杆菌引起的眼内炎，疗效分别与万古霉素、复达欣基本相当，但当眼内炎体征已明显时单次眼内用药很难完全控制炎症。     

Ecthyma gangrenosum.

Case 1. An 18-year-old white man with AML-M3 received allogeneic bone marrow transplantation (BMT) in August 1997. On the seventh day of BMT, he developed chills, fever (39.1 °C), anorexia, and perirectal pain. On physical examination, a hemorrhagic bulla and “punched out” ulceration were observed on the perirectal region. Subsequently, the ulcer was surrounded by a red, swollen, tender, cellulitic plaque ( Fig. 1 ).

Figure 1 Open in figure viewer PowerPoint The ulceration on the perianal region of the first patient     

亚胺培南或美罗培南联合利福平降低不动杆菌防耐药突变浓度的体外研究

目的在体外探讨亚胺培南(IMP)和美罗培南(MER)单用及其分别与利福平(RFP)联用对不动杆菌的防耐药突变浓度(MPC)的影响,为防止细菌耐药的产生提供理论依据。方法采用琼脂二倍稀释法,测定IMP或MER与RFP在体外单独以及联合应用的最低抑菌浓度(MIC)、计算部分抑菌浓度(FIC)指数。用肉汤法富集浓度为1010CFU/ml不动杆菌,采用琼脂平板二倍稀释法测定IMP和MER单药以及分别与RFP联用时对16株临床分离不动杆菌的MPC,并计算相应的选择指数(SI)。结果 IMP或MER分别与RFP联合应用后均以无关作用为主,未见拮抗作用,存在一定比例协同作用。IMP和MER单用对上述16株不动杆菌的SI均为16～128;分别与RFP联合使用SI均下降为1～32,联合用药较单独用药SI下降2～32倍。结论 IMP或MER分别与RFP联合使用均可降低其单用对不动杆菌的MPC,缩小MSW,防止耐药突变菌的产生。     

Biological and biomechanical effects of vancomycin and meropenem in acrylic bone cement

Antibiotic-loaded bone cement is extensively used in joint arthroplasty, but increasing bacteria resistance against common antibiotics has lead to a demand for alternative drugs. However, bone cement containing new additives must be characterized both biologically and mechanically. This study evaluated elution kinetics, antibacterial activity, and mechanical properties for cement loaded with vancomycin and/or meropenem. The presence of meropenem broadened the antibacterial spectrum and enhanced the elution of vancomycin. The mechanical properties were negatively affected by 1.0 g of vancomycin, but these detrimental effects were acceptable when only 0.5 g of vancomycin were added to a cement containing 0.5 g of meropenem. Further investigations on this formulation with adjusted antibiotic amounts are, however, necessary to reach the optimal compromise between the antibacterial and the mechanical properties of the bone cement.