目的　探讨新生儿医院感染暴发的临床特点、原因以及预防和控制措施。方法　回顾性分析新生儿重症监护病房(NICU)发生的一起肺炎克雷伯杆菌肺炎医院感染暴发事件。结果　2010年9月3日至2010年10月3日期间，NICU连续发现12例痰培养肺炎克雷伯杆菌阳性患儿，最终7例确定医院感染。患儿胎龄(28.5±2.6)周(25~32周)，出生体质量(941.4±309.8)g(620~1 540 g)，发生医院感染时的住院时间为(31.7±12.8)d (11~45 d)。总医院感染发生率2.41%，早产儿医院感染发生率为5.79%。胎龄<28周的极早早产儿医院感染发生率达到50.00%，超低出生体质量儿医院感染发生率为42.86%。所有痰培养结果均显示为多重耐药肺炎克雷伯杆菌，对青霉素类及三代头孢菌素类抗生素耐药率达到75%~100%，碳青酶烯类耐药率达到58.3%，哌拉西林/他唑巴坦耐药性最低为25.0%。所有患儿均治愈出院，无死亡病例。结论　胎龄<28周的极早早产儿及超低出生体质量新生儿是NICU医院感染暴发的高危人群。引起医院感染暴发的肺炎克雷伯杆菌耐药性已经突变至耐碳青霉烯类，需引起高度重视。规范的医疗行为是有效的医院感染防控措施，可以显著降低NICU早产儿医院感染率及死亡率。

Objectives To discuss the clinical characteristic, cause and measures to prevention and control of nosocomial infection in a neonatal intensive care unit (NICU). Methods Retrospectively analyzed an nosocomial infection outbreak of Klebsiella pneumoniae in NICU. Results From Sept. 3, 2010 to Oct. 3, 2010, there were 7 cases of hospital infection in 12 cases of sputum cultured Klebsiella Pneumoniae. The gestational age (GA) of 7 hospital infection cases was 28.5±2.6 week. The irth weight of infection cases was 941.4±309.8 g. The onset of infection was at 31.7±12.8 d of hospitalization. The nosocomial incidence was 2.41% in the hospital, which was 5.79% in preterm infants, 50.00% in GA <28w infants, and 42.86% in extremely low birth weight infant (ELBW). All sputum culture results were displayed as multi-drug resistant of Klebsiella pneumoniae, penicillin and third-generation cephalosporin antibiotic resistance rate of 75% to 100%. The resistance rates to penicillin and cephem antibiotics were 75% -100%, carbapenems was 58.3%, piperacillin/tazobactam was 25.0%. All nosocomial patients were cured. Conclusions GA <28w and ELBW infants are at increased risk of nosocomial infection in NICU. The emergence of carbapenems resistant Klebsiella Pneumoniae has been increasing with the widespread use of carbapenems. Hospital infection can be controlled by standardized medical behavior, which can decline the nosocomial infection incidence and mortality of preterm infants in NICU.