目的：调查贵阳市小儿下呼吸道感染（LRI）中的细菌及其耐药性，以指导临床合理用药。方法：收集2006年8月至2008年6月我院893 例LRI住院患儿的咽喉深部痰液标本进行细菌培养及药敏试验。结果：明确有细菌感染的为543例，阳性率为60.8%。分离出30种细菌，共计598株，其中革兰阴性杆菌533株（89.1%），革兰阳性球菌57株（9.8%）。革兰阴性菌以大肠埃希菌、肺炎克雷伯菌为主。大肠埃希菌及肺炎克雷伯菌对哌拉西林/他唑巴坦、丁胺卡那、环丙沙星、左氧氟沙星敏感，对亚胺培南高度敏感。革兰阳性球菌中以肺炎链球菌和葡萄球菌为主，肺炎链球菌对青霉素及头孢唑啉钠敏感，而葡萄球菌则对青霉素及头孢唑啉钠耐药率高，两种革兰阳性球菌均对万古霉素高度敏感，对罗红霉素耐药率高。结论：贵阳市小儿LRI的主要病原菌为革兰阴性杆菌，其中尤以大肠埃希氏菌、肺炎克雷伯菌多见，不同菌种对抗生素药物敏感性和耐药性均存在差异。应根据药敏试验合理选用抗生素治疗。［中国当代儿科杂志，2009，11（12）：964-966］

OBJECTIVE: To investigate the distribution and the antibiotic susceptibility of pathogenic bacteria in children from Guiyang with lower respiratory infection (LRI). METHODS: The nasopharyngeal aspirate samples were obtained from 893 hospitalized children with LRI between August 2006 and June 2008. An antibiotic susceptibility test was performed using the VITEK system and the Kirby-Bauer diffuse method after bacteria were identified. RESULTS: Five hundred and forty-three patients (60.8%) were bacteria-positive. A total of 598 strains (30 kinds of bacteria) were obtained from the sputum samples. Of them, 533 strains (89.1%) were gram-negative and 57 were gram-positive (9.8%). Escherichia coli (E. coli) and Kleb-siella pneumoniae (K. pneumoniae) were common in gram-negative strains. They were susceptive to piperacillin/tazobactam, amikacin, ciprofloxacin, and levofloxacin, especially to imipenem. Streptococcus pneumoniae (S. pneumoniae) and Stapthylococcus aureus (S. aureus) were common in gram-positive strains. S. pneumoniae was susceptive to penicillin and cefazolin sodium, but S. aureus was resistant. Both were high susceptive to vancomycin, and resistant to roxithromycin. CONCLUSIONS: Gram-negative bacteria are the main pathogens in children from Guiyang with LRI, and E. coli and K. pneumoniae are common. The antibiotic susceptibility of pathogenic bacteria varies with different strains of bacteria. A reasonable selection of antibiotics should be based on the antibiotic susceptibility test.［Chin J Contemp Pediatr, 2009, 11 (12):964-966］