2007—2010年NICU中细菌分布及耐药变迁的分析

The analysis of the pathogen distribution and bacterial resistance to antibiotics in NICU during 2007 to 2010

目的了解本院新生儿重症监护室(NICU)中感染性疾病细菌分布的特点和耐药性变化趋势。方法对2007年1月—2010年12月我院NICU中1521例感染性疾病住院的新生儿,根据感染部位不同分别采集痰、血、皮肤分泌物、尿、便、脑脊液、导管末端等标本进行病原菌分离培养,同时采用Kirby-Bauer法进行药敏检测,按当年NCCLS最新标准分析。结果 4年共收集2339份检测标本,检出病原菌813株,阳性分离率为34.76%,其中革兰阳性菌435株,革兰阴性菌378株,分别占分离菌株的53.5%和46.5%。前5位分离菌依次为表皮葡萄球菌(27.06%),大肠埃希菌(12.79%),阴沟肠杆菌(11.32%),金黄色葡萄球菌(11.07%)和弗氏柠檬酸杆菌(8.60%)。革兰阴性杆菌对青霉素类、头孢菌素类的耐药率显著高于亚胺培南和头孢哌酮舒巴坦(P<0.05)。肠杆菌科产ESBL酶的分离率在逐年增加。革兰阳性球菌对阿奇霉素,氨苄西林的耐药性逐年增加,达90%以上。利奈唑胺、万古霉素、替考拉宁对革兰阳性球菌抗菌活性较强。结论我院新生儿感染常见的致病菌以革兰阳性菌为主,细菌对青霉素和头孢类的的耐药率逐年增加,MRSA和ESBL仍然分别是目前革兰阳性和阴性菌中的主病原菌耐药形式。应动态监测本地区病原菌谱和细菌耐药的变迁,合理选择抗生素,降低细菌的耐药性。

Objectives To investigate distribution characteristics of the pathogenic microorganism and tendency of antibiotic resistance at NICU of our hospital. Methods Between January 2007 and December 2010, the samples of sputum, blood, skin secretions, urine, stools, cerebrospinal fluid and terminals of the conduit were collected from 1,521 hospitalized newborns with infections at the NICU, and then the samples were cultured and isolated for bacterial serotype based on infected locations and classified standards, meanwhile the test ofantibiotic resistance was conducted by method of Kirby-Bauer with respect to the newest NCCLS standards. Results During the 4-year period of time, 2,339 samples for testing were collected, and a total of 813 pathogenic bacterial strains were isolated, positive isolation rate being 34.76%, including 435 （53.5%） Gram-positive bacteria and 378 （46.5%） Gram- negative. The first five pathogenic bacteria were Staphylococcus epidermidis （27.06%）, Escherichia coli （12.79%）, Enterobacter cloacae （11.32%）, Staphylococcus aureu （11.07%） and Citrobacterfreundii （8.60%）. Drug resistance rate of the Gram-negative bacilli to penicillins and cephalosporins was significantly greater than imipenem and sulbactam cefoperazone （P〈0.05）. The isolating rate of the Enterobacteriaceae producing ESBL enzyme increasedyear by year. Drug resistance rate of gram-positive cocci to azithromycin and ampicil increased the same as above, over 90%. Linezolid, vancocin and teicoplanin were relatively active for gram-positive cocci. Conclusion Gram- positive bacteria were the major pathogen causing infections in newborn at the NICU, and antibiotic resistance rates increased to penicillins and cephalosporins over the years, MRSA and ESBL were the current major pathogenic enduring types for both Gram-positive and Gram-negative bacteria. The local pathogenic spectrum and evolution of drug resisting bacteria should be monitored dynamically, and rationale administration of antibiotics for reducing drug resistance should be promoted.