小儿急性下呼吸道感染细菌病原构成、变迁及耐药的临床研究

Clinic study on distribution and transition and drug resistance of bacteria in children with lower respir-atory tract infection

目的对昆明地区急性下呼吸道感染（acute low respiratory infection，ALRI）患儿进行连续9年监测及临床研究，了解患儿细菌病原菌构成、变迁及对常用抗生素的耐药性。方法对昆明市儿童医院2002年1月至2010年12月因ALRI住院的患儿痰液培养的致病菌株进行临床分析及研究，对分离菌株进行药敏试验。结果病原菌构成情况：（1）病原菌总阳性率18．52％（3006／16229），其中革兰阴性杆菌占75．35％，革兰阳性球菌占20．23％，真菌占4．42％；病原菌前5位依次为大肠埃希菌、肺炎克雷白杆菌、肺炎链球菌、流感嗜血杆菌、阴沟肠杆菌。（2）监护病房ALRI病原菌以革兰阴性菌为主，主要为大肠埃希菌、肺炎克雷白杆菌；革兰阳性菌以金黄色葡萄球菌为主。普通病房革兰阴性菌中，流感嗜血杆菌取代大肠埃希菌，成为最常见的病原菌，革兰阳性菌以肺炎链球菌为主。病原菌的耐药情况：后4年与前5年比较，病原菌总体耐药情况呈上升趋势，部分达90％左右，并呈多重耐药状态；未发现对亚胺培南及万古霉素耐药的菌株；大肠埃希菌和肺炎克雷白杆菌产超广谱β-内酰胺酶菌株检出率呈上升趋势。结论昆明地区9年间小儿ALRI细菌病原菌以革兰阴性杆菌为主，其中大肠埃希菌为首位；不同病房病原构成、变迁均不同；病原菌总体耐药情况呈上升趋势。

Objective To investigate the distribution, transition and changes of drug resistance of bacteria in children with acute lower respiratory tract infection （ ALRI） of Kunming by conducting a consecu-tive clinical study of 9 years. Methods Sputum specimens for bacterial cultures were collected from children with ALRI who had been admitted to ICU and general wards of Kunming Children＇s Hospital from Jan 2002 to Dec 2010. Antibiotic susceptibility tests were performed after bacteria had been identified. Results Patho-genic bacteria distribution： （ 1 ） total positive rate of pathogenic bacteria was 18. 52% （3006/16 229） ;gram-negative bacteria accounted for 75.35% ; gram-positive bacilli accounted for 20. 23% ; fungi accounted for 4.42% ;Escherichia coli was the most common pathogenic bacteria in children with ALRI, followed by Kleb-siella pneumonia, Streptococcus pneumoniae, Hemophilus, Enterobacter cloacae, Pseudomonas aemginosa. （2） Gram-negative bacteria such as Escherichia coli and Klebsiella pneumonia were the two most common bacteria in ICU, Staphylococcus aureus was the most common gram-positive bacteria in ICU;while Hemophi-lus took the palace of Klebsiella pneumonia as the second most common gram-negative bacteria in general wards;Streptococcus pneumoniae was the most common gram-positive bacteria in general wards. Drug resist- ance： compared with the years of 2002 - 2006,the rate of drag resistance between 2007 and 2010 had in-creased, and multiple drag resistance status was present. Resistant strains to imipenem and vancomycin were not found. Constituent ratio and proportion of Escherichia coli and Klebsiella pneumoniae producing extended spectrum β-1actamases showed the trend of increase by years. Conclusion Gram-negative bacilli were the main bacteria pathogens in children with ALRI in Kunming between 2002 and 2010, among which escherichia coli was the most common pathogen. Bacteria distribution and transition were different in different wards. The drug resistance of bacteria showed the trend of increase in the recent years.