广州地区儿童血培养病原菌的分布及耐药性研究

目的探讨儿童血培养病原菌的分布特点及其耐药情况，为临床诊疗提供参考。方法对广州市儿童医院2005年至2006年临床各科室送检血液标本所分离病原菌的分布及药敏结果进行回顾性分析。结果共检出385株病原菌，其中革兰阳性菌208株，占54．0％，革兰阴性菌164株，占42．6％，真菌13株，占3．4％。分离率前6位的病原菌依次为凝固酶阴性葡萄球菌（CNS，35．8％）、肺炎克雷伯菌（8．8％）、不动杆菌（5．5％）、大肠埃希菌（4．9％）、铜绿假单胞菌（4、7％）、金黄色葡萄球菌（4．4％）。病原菌的病区分布特点：儿科重症监护病房以不动杆菌等非发酵菌为主要分离菌（占41．7％），新生儿重症监护病房以CNS为主（40．5％），血液病区以肠杆菌科细菌为主（35．7％），新生儿病房及传染病房均以CNS为主要分离菌。CNS对青霉素、氨苄西林、红霉素耐药率均超过80％，但对万古霉素、替考拉宁和阿米卡星敏感，MRCNS检出率达72.5％。肠杆菌科细菌对哌拉西林、氨苄西林、头孢噻肟及头孢哌酮的耐药率为50％～100％，但对亚胺培南、阿米卡星和诺氟沙星耐药率较低。不动杆菌对广谱青霉素、第3代头孢菌素、氨曲南及庆大霉素的耐药率较高而对亚胺培南、头孢哌酮／舒巴坦较为敏感。结论凝固酶阴性葡萄球菌是广州地区儿童败血症最主要的病原菌。不同病区检出病原菌种类有较大差异。根据病原菌种类及药敏结果合理应用抗菌药是有效控制感染和减少耐药菌株产生的重要手段。

Analysis of the distribution and antibiotic resistance of pathogenic bacteria isolated from blood samples of pediatric patients in Guangzhou

Objective To investigate the distribution and antibiotic resistance of pathogenic bacteria isolated from blood samples of pediatric patients and to provide essential information regarding the selection of antibiotic therapy for septicaemia. Methods All the blood samples isolated from patients in Guangzhou Children＇s Hospital between January 2005 and December 2006 were cultivated with Bactec9120 blood culture apparatus. Pathogenic bacteria were identified with API system and drug sensitivity tests were conducted with K-B method. Results Totally 385 strains of bacteria were isolated. 208 strains of gram positive bacteria were isolated and accounted for 54%. Gram negative bacteria and fungi accounted for 42.6% and 3.4% respectively. Coagulase-negative staphylococcus was the dominant strains and comprised 35.8% of all isolates ,followed by Klebsiella spp （ 8.8% ）, Acinetobacter （ 5.5% ）, Escherichia coli（ 4.9% ）, Pseudomonas aeruginosa （ 4.7 % ） and Staphylococcus aureus （4.4%）. The main pathogenic bacteria in PICU was Acinetobacter and in NICU was Coagulase-negative staphylococcus,in hematopathy district was Enterobacteriaceae. The antibiotic resistance rate of Coagulase-negative staphylococcus against penicillin, ampicillin and erythromycin were more than 80%, but to vancomycin,teicoplanin and amikacin were lower. Enterobacteriaceae were susceptible to imipenem, amikacin and noriloxacin,whereas the resistance rate of them to ampicillin, piperacillin and third generation cephalosporins were high. Acinetobacter was resistant to most of monitored antibiotics,except for imipenem, cefoperazone/sulbactam. Conclusions Coagulase-negative staphylococcus was the most frequently isolated from blood samples of pediatric patients in Guangzhou. The distribution and antibiotic susceptibility of pathogenic bacteria should be considered when selecting antibiotic treatment in children with septicaemia.