免疫缺陷患者医院革兰阳性球菌感染特性

Epidemiological investigation of nosocomial infection of gram-positive cocci in immunocompromised patients

目的前瞻性调查220例继发免疫缺陷合并医院革兰阳性球菌感染患者的临床表现、细菌学分布特点及其耐药性,为经验性抗感染治疗提供临床依据。方法收集2007年4月—2009年2月在上海交通大学附属第一人民医院、中国医科大学附属第一医院诊断为继发免疫缺陷合并医院革兰阳性球菌感染的住院患者220例,记录入选前3周患者的病史资料,采用K-B纸片扩散法按统一方案对临床分离菌进行抗药物敏感试验。按2008年美国临床实验室标准化协会(CLSI)标准判断细菌鉴定及药物敏感的结果。结果 220例免疫缺陷患者中,革兰阳性球菌感染患者的症状、体征不典型,主要以发热为主。微生物学检查共分离出革兰阳性球菌237株,甲氧西林金黄色葡萄球菌对常见抗生素的耐药率显著高于甲氧西林敏感的金黄色葡萄球菌(P值均<0.05),未发现万古霉素、替考拉宁和利奈唑胺耐药的葡萄球菌。金黄色葡萄球菌共98株,其中64.3%为耐甲氧西林金黄色葡萄球菌。凝固酶阴性葡萄球菌共87株,其中耐甲氧西林阴性葡萄球菌占71.3%。肠球菌共45株,其中粪肠球菌28株,屎肠球菌17株,粪肠球菌对庆大霉素、阿莫西林/克拉维酸、氨苄西林/舒巴坦纳、左氧氟沙星、利福平的耐药率低于屎肠球菌(P值均<0.05),1株屎肠球菌对万古霉素耐药,未发现对替考拉宁和利奈唑胺耐药的菌株。结论免疫缺陷患者医院革兰阳性球菌感染的临床表现多样,对常见抗生素的耐药率高,须及早采取防控措施。

Objective To prospectively investigate clinical manifestations, bacterial distribution, and antimicrobial resistance in 220 patients with secondary immunodeficiency and nosocomial infection of gram-positive cocci. Methods From April 2007 to February 2009,220 patients hospitalized to Shanghai First People＇s Hospital affiliated to Shanghai Jiaotong University and the First Hospital affiliated to China Medical University, and were diagnosed as secondary immunodeficiency and nosocomial infection of gram-positive cocci. The clinical data were recorded within three weeks prior to the enrollment. Susceptibility test was performed according to K-B method. The testing results were assessed according to the Clinical and Laboratory Standards Institute （CLSI） 2008. Results The symptoms and signs of bacterial infection were atypical in the 220 patients. Most of the patients suffered from fever. A total of 237 gram-positive cocci strains were isolated from the specimens. Antimicrobial resistance of methicillin-resistant Staphylococcus oureus （MRSA） was significantly stronger than MSSA. No staphylococci strains were resistant to vancomycin, teicoplanin or linezolid. There were 98 strains of Staphylococcus oureus and MRSA accounted for 64.3% of them. There were 87 strains of Ccacj^lase-negative staphylococci and MRCNS accounted for 71.3% of them. There were 45 strains of enterococci including 28 Enterococcus faecalis and 17 Enterococcus feces. Antimicrobial resistance of Enterococcus faecalis was weaker than Enterococcus feces, One of the Enteroceccus feces was resistant to Vancomycin. No enterococci strains were resistant to teicoplanin or linezolid. Conclusions The clinical manifestations are varied in the irnmunocompromised patients with nosocomial infection of gram-positive cocci. The bacterial resistance to cornmon antibiotics is increasing. It is urgent to take effective measures to prevent antimicrobial resistance.