论文部分内容阅读
目的 监测我国2004-2010年主要城市三级甲等医院住院患者血标本中致病菌的耐药状况及其耐药特点.方法 所有收集的血标本来源菌株统一由中心实验室(北京大学第一医院临床药理研究所)采用美国临床和实验室标准协会(CLSI)推荐的平皿2倍稀释法测定抗菌药物的MIC值,并根据CLSI 2011颁布的抗菌药物临界浓度标准进行耐药性分析.结果 2004-2005、2007-2008和2009-2010年革兰阳性菌和阴性菌分离率没有明显变化,3个年度革兰阳性菌的分离率分别为43.1％ (149/346)、34.0％ (151/444)和47.5％(776/1634),革兰阴性菌分别为56.9％(197/346)、66.0％(293/444)和52.5％(858/1634).耐甲氧西林的金黄色葡萄球菌(MRSA)的检出率2007-2008年最高(54.1％,20/37),2009-2010年度有所下降(36.5％,62/170).3个年度甲氧西林耐药的凝固酶阴性葡萄球菌(MRCNS)的检出率相近.2009-2010年检测到1株(1.8％,1/56)对万古霉素耐药的屎肠球菌,1株对利奈唑胺耐药的粪肠球菌(MIC值为8 mg/L).肺炎链球菌的耐药性监测结果发现,与2007-2008年相比,2009-2010年虽然口服青霉素不敏感菌株检出率没有增加,分别为54.5％(6/11)和53.9％ (7/13),但耐药株检出率从未检出增加到30.8％ (4/13).按肺炎链球菌非颅内感染株静脉给药折点标准判定,2007-2008年肺炎链球菌对青霉素的敏感度为100.0％(11/11),2009-2010年敏感度下降至84.6％(11/13).3个年度大肠埃希菌中产超广谱β-内酰胺酶(ESBL)的菌株检出率相似,分别为66.7％(30/45)、73.2％(71/97)和67.9％(233/343),肺炎克雷伯菌中产ESBL菌株的检出率逐年下降,2004-2005年、2007-2008年和2009-2010年依次为72.4％(21/29)、50.0％ (18/36)和41.1％(65/158).纵观3个年度碳青霉烯类抗菌药物敏感性检测结果,肠杆菌科细菌对碳青霉烯类药物的敏感度均在90％以上,耐药率＜5％.多重耐药或泛耐药以鲍曼不动杆菌最为严重.2009-2010年监测中发现多重耐药率为81.8％(81/99),此外,还发现了1株泛耐药鲍曼不动杆菌(1.0％,1/99).结论 细菌对抗感染药物的耐药现状形势严峻,鲍曼不动杆菌耐药最为明显,常呈现多重耐药特点,甚至泛耐药.碳青霉烯类抗菌药物仍然是抗肠杆菌科细菌最有效的药物.已发现对利奈唑胺和替加环素等新型抗菌药物的耐药菌株.“,”Objective To investigate the resistance profiles and the trend of bloodstream-infecting pathogens isolated from hospitalized patients during 2004-2010.Methods The bloodstream isolates were collected from 18 hospitals in 17 cities.Minimum inhibition concentrations (MIC) were determined using the agar dilution method recommended by CLSI (Clinical and Laboratory Standards Institute),and susceptibility results were analyzed according to the 2011 CLSI guideline.Results Among the 2004-2005,2007-2008 and 2009-2010 periods,the proportions of clinical isolates were similar; 43.1％ (149 isolates),34.0％ (151 isolates) and 47.5％ (776 isolates) for Gram positive strains,56.9％ (197 isolates),66.0％ (293 isolates) and 52.5％ (858 isolates) for Gram negative strains,respectively.The isolating rate of MRSA was 54.1％ (20/37) in 2007-2008,which was the highest among the 3 periods during 2004 to 2010,while it decreased in 2009-2010 (36.5％,62/170).The MRCNS proportions were similar across the 3 periods.One (1.8％) vancomycin-resistant Enterococcus faecium and 1 linezolidresistant Enterococcus faecalis were found.Although the isolating rates of penicillin non-sensitive strains (oral) were similar between 2009-2010 and 2007-2008 [54.5％ (6/11) and 53.9％ (7/13),respectively],the resistant rates increased from 0％ in 2007-2008 to 30.8％ (4/13) in 2009-2010.The results were similar according to the non-meningitis criterion (Ⅳ),and the susceptibility rates decreased from 100.0％ (11 isolates) in 2007-2008 to 84.6％ (11/13) in 2009-2010.ESBL-harboring strains in E.coli were similar among the 3 periods during 2004 to 2010 [66.7％ (30/45),73.2％ (71/97) and 67.9％ (233/343),respectively].ESBL-producing strains in Klebsilla pnuemoniae decreased year after year,72.4％ (21/29),50.0％ (18/36) and 41.1％ (65/158) in 2004-2005,2007-2008 and 2009-2010,respectively.Except that the sensitive rate of Enterobacter cloacae to ertapenem was 80％ (32/40),the sensitive rates of other strains to carbapenems were still above 90％ and the resistance rates were less than 5 ％.Acinetobacter baumannii had the highest multi-drug resistance rate (81.8 ％,81/99).One strain (1.0％,1/99) of Acinetobacter baumannii isolated in 2009-2010 was reported to be pan-resistant.Conclusions We are facing a more serious situation of bacterial resistance.Acinetobacter baumannii resistance was most serious,usually with the characteristics of multiple drug resistance,and even panresistance.Carbapenems remain to be the most effective against enterobacteriaceae.Strains resistant to novel antibiotics (linezolid and tigecycline) have emerged.