Sahm D F, Marsilio M K, Piazza G
MRL Pharmaceutical Services, Herndon, Virginia 20171, USA.
Clin Infect Dis. 1999 Aug;29(2):259-63. doi: 10.1086/520195.
To assess the prevalence of antimicrobial-resistant pathogens among the most common bloodstream isolates, we examined antimicrobial susceptibility data from The Surveillance Network Database-USA, an electronic surveillance system that collects data from 118 clinical microbiology laboratories across the United States. Between 1995 and 1997, resistance to both vancomycin and ampicillin was much more prevalent among Enterococcus faecium than Enterococcus faecalis, suggesting the need for laboratories to identify to species. When staphylococcal isolates were examined for reduced susceptibility to vancomycin (minimum inhibitory concentration = 4 microg/mL), the frequency was highest in methicillin-resistant coagulase-negative staphylococci. We also learned that nonsusceptibility to ceftazidime in Klebsiella pneumoniae was more prevalent among isolates from blood (12.7%) than among isolates from urine (7.1%) or respiratory sources (9.3%). Although antimicrobial resistance is low overall for isolates of Escherichia coli from blood, the prevalence of cefoxitin resistance among ceftazidime-resistant strains (61.9%) suggests the action of mechanisms other than extended-spectrum beta-lactamase.
为评估最常见的血流感染分离菌中抗菌药物耐药病原体的流行情况，我们检查了美国监测网络数据库的抗菌药物敏感性数据，该数据库是一个电子监测系统，收集来自美国118家临床微生物实验室的数据。1995年至1997年期间，屎肠球菌对万古霉素和氨苄西林的耐药率比粪肠球菌高得多，这表明实验室需要鉴定到菌种。当检测葡萄球菌分离株对万古霉素的敏感性降低（最低抑菌浓度=4μg/mL）时，耐甲氧西林凝固酶阴性葡萄球菌的发生率最高。我们还了解到，肺炎克雷伯菌对头孢他啶的不敏感性在血液分离株中（12.7%）比尿液分离株（7.1%）或呼吸道来源分离株（9.3%）更普遍。尽管血液中分离的大肠埃希菌总体抗菌药物耐药率较低，但头孢他啶耐药菌株中头孢西丁耐药率（61.9%）表明存在超广谱β-内酰胺酶以外的耐药机制。
