Bratu Simona, Tolaney Pooja, Karumudi Usha, Quale John, Mooty Mohamad, Nichani Satyen, Landman David
Department of Medicine, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA.
J Antimicrob Chemother. 2005 Jul;56(1):128-32. doi: 10.1093/jac/dki175. Epub 2005 May 25.
To describe the molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae in Brooklyn, NY and assess the in vitro activity of various antibiotic combinations.
Clinical isolates with suspected carbapenem resistance were referred to the central research laboratory from August 2003 to June 2004. Isolates underwent MIC testing, ribotyping, and were analysed for the presence of KPC carbapenemases. Time-kill studies using various antibiotic(s) were performed on selected isolates.
Ninety-six isolates were referred from 10 Brooklyn hospitals. All isolates were resistant to the carbapenems with most having MICs >32 mg/L. Few were susceptible to fluoroquinolones and cephalosporins; approximately half were susceptible to aminoglycosides, and 90% to polymyxin B. Two-thirds were susceptible to doxycycline, and all were considered susceptible to the investigational glycylcycline antibiotic tigecycline. Virtually all possessed bla(KPC), and over 80% belonged to one ribotype. In time-kill studies involving 16 isolates, tigecycline demonstrated bacteriostatic activity and polymyxin B concentration-dependent bactericidal activity. The combination of polymyxin B at 0.5 x MIC plus rifampicin had synergic activity against 15/16 isolates, including two polymyxin-resistant strains. The combination of polymyxin B plus imipenem had synergic bactericidal activity against 10/16 isolates, but was antagonistic for three isolates.
Multiresistant K. pneumoniae with bla(KPC) are present in multiple hospitals in New York City. The most consistently active agents in vitro were tigecycline and polymyxin B, particularly when the latter was combined with rifampicin. The clinical efficacy of these agents remains to be determined.
描述纽约布鲁克林耐碳青霉烯类肺炎克雷伯菌的分子流行病学特征，并评估各种抗生素组合的体外活性。
2003年8月至2004年6月，将疑似耐碳青霉烯类的临床分离株送至中央研究实验室。分离株进行了最低抑菌浓度（MIC）检测、核糖体分型，并分析了KPC碳青霉烯酶的存在情况。对选定的分离株进行了使用各种抗生素的时间杀菌研究。
从布鲁克林的10家医院转诊了96株分离株。所有分离株均对碳青霉烯类耐药，大多数MIC>32mg/L。很少有分离株对氟喹诺酮类和头孢菌素敏感；约一半对氨基糖苷类敏感，90%对多粘菌素B敏感。三分之二对多西环素敏感，所有分离株均被认为对研究用甘氨酰环素类抗生素替加环素敏感。几乎所有分离株都携带bla(KPC)，超过80%属于一种核糖体分型。在涉及16株分离株的时间杀菌研究中，替加环素表现出抑菌活性，多粘菌素B表现出浓度依赖性杀菌活性。0.5倍MIC的多粘菌素B加 rifampicin的组合对15/16株分离株具有协同活性，包括两株耐多粘菌素菌株。多粘菌素B加亚胺培南的组合对10/16株分离株具有协同杀菌活性，但对三株分离株具有拮抗作用。
携带bla(KPC)的多重耐药肺炎克雷伯菌存在于纽约市的多家医院。体外活性最稳定的药物是替加环素和多粘菌素B，特别是后者与rifampicin联合使用时。这些药物的临床疗效仍有待确定。
