血液肿瘤合并感染病原菌流行病学及耐药性研究

目的　了解血液肿瘤合并感染病原菌分布的特点及耐药性变化。方法　 1998～ 2 0 0 2年上海第二医科大学瑞金医院血液科各种培养所检出的细菌菌种 ,运用WHONET5软件进行数据统计分析。结果　血液科分离得到 5 36株菌株 ,其中革兰阳性菌 2 30株 (4 2 .9% ) ;革兰阴性菌 30 1株(5 6 .2 % )。居前 6位的革兰阴性菌分别为铜绿假单胞菌、肺炎克雷伯菌、阴沟肠杆菌、大肠埃希菌、鲍曼不动杆菌和嗜麦芽窄食单胞菌。大肠杆菌和克雷伯菌属超广谱 β 内酰胺酶 (ESBL)产生率为2 7.3%和 33.3%。耐甲氧西林凝固酶阴性葡萄球菌为血液肿瘤患者最易感染的革兰阳性菌 ,达 88.5 %。对革兰阴性菌整体而言 ,亚胺培南平均耐药率仅为 11.4 %。治疗产ESBL的菌株感染 ,碳青霉烯类抗生素、头孢吡肟、酶抑制剂是最好的选择。鲍曼不动杆菌对第三代头孢菌素的耐药率维持在 2 5 .0 %～4 1.3% ,对第四代头孢菌素的耐药率为 2 2 .7% ,对碳青霉烯类耐药率为 12 .7%。铜绿假单胞菌对碳青霉烯类抗生素耐药率可达 14 .5 % ,对第三代头孢菌素敏感性较好。结论　应根据血液科细菌分布的特点 ,有针对性地合理应用抗生素。

Epidemiology and drug resistance of the pathogenic microbes in the complicated infection of hematological malignancies

OBJECTIVE: To investigate the epidemiological characteristics and drug resistance profile of the infection in patients with hematological malignancies. METHODS: All the microbe strains isolated from the department of hematology in Ruijin hospital between 1998 and 2002 were collected for the assessment of antimicrobial susceptibility and the results were analysed by WHONET5 software. RESULTS: Out of the 536 strains isolated in the department of hematology, 230 (42.9%) were Gram positive and 301 (56.2%) Gram negative organisms. The first 6 strains of Gram (-) microbes in frequent order were Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterobacter cloacae, Escheriahia coli, Alinetobacter Baumannii and Stenotrophomonas (xantho) maltophi. The extended spectrum beta-lactamase (ESBLs) producing rates of Escheriahia coli and Klebsiella pneumoniae were 27.3% and 33.3%, respectively. Methylcillin resistant coagulase negative staphylococcus (MRCNS) was the most prevalent Gram (+) bacteria in the complicated infection patients with hematological malignancies, which accounted for 88.5%. Carbapenems were most sensitive for all of the gram negative bacteria, with a drug resistance rate of 11.4 (5.0% approximately 15.8%) of imipenem. For ESBLs strains, carbapenems and cefapime were the best choice, with the resistance rate of 46.4% approximately 94.4% and 50.0% approximately 75.9%, respectively. The drug resistance rate of Alinetobacter Baumannii was 25.0% approximately 41.3% for the third generation cephalosporin, 22.7% for the fourth generation cephalosporin and 12.7% for imipenem. Pseudomonas aeruginosa was resistant to carbapenems, with a resistance rate of 12.7% of imipenem; however, it was more sensitive to the third generation cephalosporin. CONCLUSION: Antibiotics should be rationally administrated with more considerations to the characteristics of epidemiology and drug resistance profile of the microbes in the given department of hematology.