2002—2003年中国医院和社区获得性感染革兰阳性细菌耐药监测研究

2002—2003 Bacterial resistance surveillance on Gram-positive cocci isolated from hospital acquired infections and community acquired infections in China

目的 监测我国不同地区医院获得性感染(HAI)与社区获得性感染(CAI)患者中革兰阳性球菌耐药状况。方法 按原设计方案对 14家医院 31个研究病房,从 2002年 7月 1日至 2003年 6月30日年度内分离的 770株革兰阳性球菌,采用国际标准平皿二倍稀释法进行体外敏感试验,以MIC50、MIC90表示抗菌药物的抗菌活性,并按 2002年美国实验室标准委员会 (NCCLS)指导原则的标准计算细菌对抗菌药物的耐药率(R)%、中介率(I)%和敏感率 (S)%。结果 从住院感染患者中分离到葡萄球菌 390株,甲氧西林耐药金黄色葡萄球菌(MRSA)与甲氧西林耐药表皮葡萄球菌 (MRSE)的检出率分别为 41 0% (68 /166)与 29 1% (34 /117), 苯唑西林耐药金黄色葡萄球菌(ORSA)与苯唑西林耐药表皮葡萄球菌(ORSE)的检出率分别为 41 6% (69 /166)和 82 1% (96 /117)。HAI患者中MRSA与ORSA检出率均为 60 7% (17 /28),显著高于CAI患者中MRSA与ORSA检出率,后两者分别为 37 0% (51 /138)与37 7% (52 /138)。未发现对万古霉素、去甲万古霉素耐药或中介金黄色葡萄球菌或凝固酶阴性葡萄球菌菌株。青霉素耐药肺炎链球菌(PRSP+PISP)的总耐药率为 35 3% (12 /34),包括耐药率R% (2 9%,1 /34)和中介率I% (32 4%, 11 /34)。从研究病房分离到肠球菌 220株。

Objective To determine the drug resistance rate of Gram positive cocci isolated from patients with hospital acquired infection (HAI) or community acquired infection (CAI) in 31 study wards of 14 hospitals located at different areas in China Methods According to the previous protocol, from July 1st 2002 to June 30th 2003, a total of 770 pathogenic strains of Gram positive cocci isolated from 14 hospitals were collected for in vitro susceptibility test using the international standard plate dilution method to assay the MIC 50 and MIC 90 as indicators representing the antibacterial activity of antimicrobial agents The resistant rate (R%), intermediate rate (I%) and susceptibility rate (S%) of drugs were calculated according to the criteria in guidelines of NCCLS (2002) Results The rates of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant Staphylococcus epidermidis (MRSE) were 41 0% (68/166) and 29 1% (34/117) respectively The rates of oxacillin resistant Staphylococcus aureus (ORSA) and oxacillin resistant Staphylococcus epidermidis (ORSE) were 41 6% (69/166) and 82 1% (96/117) respectively Among the total of 166 strains of S aureus , 138 strains were isolated from patients with CAI and 28 strains were from HAI patients The rates of MRSA and ORSA from HAI patients were the same 60 7% (17/28) which were significantly higher than those from CAI patients The rates of MRSA and ORSA from CAI patients were 37 0% (51/138) and 37 7% (52/138) respectively ( P <0 01) Neither strains of S aureus nor strains of coagulase negative Staphylococcus were found resistant to vancomycin and norvancomycin The total resistant rate of penicillin resistant Streptococcus pneumoniae (PRSP+PISP) was 35 3% (12/34), including a R% of 2 9% (1/34)(PRSP) and I% of 32 4% (11/34)(PISP) 315 strains of Enterococcus were isolated, including 220 strains from the study wards and 95 strains from other wards Among them, 251 strains were identified as E faecalis , 58 strains as E faecium , the ratio of strain number of E faecalis vs E faecium was 4 3∶1 The rate of ampicillin resistant E faecium (AREF) was 72 4% (42/58) which was significantly higher than that of ampicillin resistant E faecalis 37 5% (94/251) 5 Van B type strains (2%, 5/251)) of E faecalis were found intermediate to vancomycin and 3 Van A type strains (5 2%, 3/58) of E faecium were found resistant to vancomycin, norvancomycin and teicoplanin Conclusion The drug resistant rates of Gram positive cocci including MRSA, ORSA, PRSP (R+I) and AREF etc in present study were similar to or slightly increased in comparison with those in the 2000 2001 report of China BRSSG, and they were approximately consistent with some literatures reported from the western pacific region No strain of S aureus was found resistant or intermediate to vancomycin Three Van A type strains of E faecium were found resistant to all of three glycopeptides tested