Abstract: AbstractObjectiveTo analyze the condition of bacterial colonization and risk factors of the colonized bacteria on premature infants in NICU.MethodsBacterial surveillance was done on every premature infant enrolled in our study from May 2002 to April 2003.Nasopharyngeal and rectal swab culture was done immediately at hospital admission and then once a week.The clinical data,such as the kind of antibiotic used,the condition of colonized bacteria,were collected and analyzed by SPSS software.ResultsAmong 183 strains of bacteria isolated from 11 cases at the admission,52 cases after hospitalization,62.8% were Gramnegative organisms.The risk factors for colonization were gestational age,birth weight,length of hospitalization,mechanical ventilation,parenteral nutrition and length of antibiotic therapy.The most susceptible antibiotic for the Gramnegative organisms obtained from our study was meropenem,but it was also easy to cause the colonization of coagulase negative staphylococcus(MRScoN).Gramnegative organisms was the main pathogens of sepsis and the fastigium was in one week of colonization.ConclusionWe suggest that bacterial surveillance culture should be taken for premature infants in NICU.It is most important to prevent the colonization by restricting the use of antibiotic,shortening the length of hospital stay and reducing the use of parenteral nutrition.

Key words: Nosocomial infection , Premature, Bacterial colonization

摘要： 目的了解NICU中住院早产儿的细菌定植状况及定植菌的耐药性。方法对2002年5月至2003年4月间在北京协医院NICU住院治疗的早产儿进行细菌学监测，于入院时和入院后每周常规做咽拭子及直肠拭子培养。收集每位早产儿的临床及实验室资料，对结果进行统计学分析。结果147例早产儿共培养出183株定植菌。入院当天即有细菌定植者11例，入院后发生细菌定植者52例。定植菌以革兰阴性杆菌为主(占62.8%)。早产儿获得细菌定植与胎龄小、出生体重低、住院时间长、应用机械通气、胃肠外营养、长时间使用抗生素等因素有关。美罗培南在目前所用抗生素中对革兰阴性杆菌敏感性最高，但与耐甲氧西林凝固酶阴性葡萄球菌(MRScoN)定植之间具有相关性。败血症以革兰阴性杆菌为主，细菌定植1周左右为败血症高发期。结论应对在NICU住院的早产儿进行细菌学监测，根据监测结果判断细菌定植状态和采取保护措施。控制抗生素使用、缩短住院时间和胃肠外营养的时间，对控制早产儿细菌定植将起到重要作用。

关键词: 婴儿, 早产, 细菌定植, 院内感染