社区获得性与医院获得性MRSA感染监测

Surveillance on infections caused by community-associated and healthcareassociated MRSA

目的了解社区获得性耐甲氧西林金黄色葡萄球菌（CA-MRSA）与医院获得性MRSA（HA-MRSA）的耐药特征，为临床经验性选择抗菌药物提供参考依据。方法回顾性分析某院中医外科和重症监护室（ICU）2006年1月-2008年12月临床标本中分离的MRSA菌株资料，并对2个病区分离的CA-MRSA、HA-MRSA及其耐药性进行统计分析。结果ICU分离的87株MRSA来源：痰液71株，咽拭子6株，伤口分泌物5株，血液、静脉穿刺管各2株，胸腔积液1株；其中HA-MRSA占98．85％（86／87）。中医外科的41株MRSA均分离自伤口脓液，其中CA-MRSA占48．78％（20／41），且有逐年上升趋势，由2006年的20．00％上升至2008年的71．43％（χ^2=8．24，0．01〈P〈0．025）。药敏结果显示，HA-MRSA对克林霉素（98．13％）、四环素（98．13％）、红霉素（100．00％）、环丙沙星（100．00％）、左氧氟沙星（100．00％）、庆大霉素（100．00％）的耐药率显著高于CA-MRSA（分别为42．86％、66．70％、33．33％、0．00％、0．00％、4．76％），两两比较，差异均有统计学意义（均P％0．005）。结论住院患者中CA-MRSA感染呈上升趋势。CA-MRSA与HA-MRSA的耐药性并不一致，对非β-内酰胺类抗菌药物多敏感。

Objective To analyze the drug resistance of community-associated methicillin-resistant Staphylococcus aureus （CA-MRSA） and healthcare -associated MRSA（HA-MRSA）, so as to provide reference on empirical antimicrobial therapy for treating MRSA infection. Methods MRSA isolated from clinical specimens from surgical department and intensive care unit （ICU） in a hospital between January 2006 and December 2008 were analyzed retrospectively , distribution and drug resistance of CA-MRSA and HA-MRSA were analysed statistically. Results Eightseven＇strains were from ICU , the sources were as follows： 71 strains were from sputum, 6 from throat swabs, 5 from wound secretion, 2 from blood and venipuncture tubes respectively, and 1 from pleural effusion; HA-MRSA accounted for 98. 85% （86/87）. Forty-one MRSA strains from surgical department were all isolated from wound pus, CA-MRSA accounted for 48. 75% （20/41） , and showed an increasing tendency year by year, which increased from 20. 00% in 2006 to 71.43% in 2008 （χ^2 = 8. 24, 0. 01〈P〈0. 025）. Antimicrobial susceptibility test results showed that the resistant rates of HA-MRSA to clindamycin, tetracycline, erythromycin, ciprofloxacin, levofloxacin , and gentamycin was 98. 13 %, 98.13 %, 100. 00 %, 100. 00 %, 100. 00 % , and 100. 00 % respectively, which was significantly higher than that of CA-MRSA （which was 42. 860./00,66. 70%,33. 33%0,0. 00%,0. 00% , and 4. 76% respectively）, there was significant difference between the two respectively（all P〈0. 005）. Conclusion There is an increasing tendency of CA-MRSA infection in hospitalized patients , drug resistance of CA-MRSA is different from that oF HA- MRSA , CA-MRSA strains are usually susceptible to non-βlactam agents.