皮特不动杆菌、医院不动杆菌感染的临床特点及同源性

目的 了解某院皮特不动杆菌、医院不动杆菌感染的临床特点及其同源性。方法 收集2016年1-12月分离自该院临床送检感染标本的335株醋酸钙不动杆菌-鲍曼不动杆菌复合群（ACB）非重复菌株，采用16S-23S rRNA基因间隔区序列分析鉴定到种，比较皮特不动杆菌、医院不动杆菌和鲍曼不动杆菌培养阳性患者的临床资料及实验室检查结果，采用PCR方法检测3种细菌OXA-51基因，并采用随机扩增多态性DNA（RAPD）技术分析皮特不动杆菌和医院不动杆菌的同源性。结果 335株ACB包括皮特不动杆菌18株，医院不动杆菌23株和鲍曼不动杆菌284株，其他不动杆菌10株。鲍曼不动杆菌和皮特不动杆菌/医院不动杆菌分离患者间ICU入住率、侵入性操作情况、肺部感染率、住院期间死亡率比较，差异均有统计学意义（均P<0.05）；皮特不动杆菌和医院不动杆菌对大多数抗菌药物的耐药率低于鲍曼不动杆菌。皮特不动杆菌和医院不动杆菌均未见OXA-51基因扩增阳性，284株鲍曼不动杆菌OXA-51基因PCR检测均阳性。RAPD技术将皮特不动杆菌和医院不动杆菌分为4个不同的克隆，同源性分析显示，克隆A和克隆F分别为皮特不动杆菌、医院不动杆菌的流行株。结论 皮特不动杆菌和医院不动杆菌应被视为与鲍曼不动杆菌不同的临床菌株而区分对待，OXA-51基因扩增可以考虑作为一种简便快捷的分子生物学技术用于皮特不动杆菌和医院不动杆菌的快速鉴定。应加强对皮特不动杆菌和医院不动杆菌的监控。

Clinical features and homology of Acinetobacter pittii and Acinetobacter nosocomialis infection

Objective To understand clinical features and homology of Acinetobacter pittii (A. pittii) and Acinetobacter nosocomialis (A. nosocomialis) infection in a hospital. Methods A total of 335 non-duplicate clinical isolates of Acinetobacter calcoaceticus-Acinetobacter baumannii complex (ACB) were collected from a hospital between January 2016 and December 2016, species were identified by 16S-23S rRNA gene spacer sequence analysis, clinical data and laboratory detection results of A. pittii, A. nosocomialis and A. baumannii were compared, OXA-51 gene of three kinds of bacteria was detected by polymerase chain reaction(PCR), homology between A. pittii and A. nosocomialis was analyzed by randomly amplified polymorphic DNA (RAPD). Results Among 335 ACB strains, 18, 23, 284, and 10 were A. pittii, A. nosocomialis, A. baumannii, and other Acinetobacter respectively. There were significant differences in admission rate of intensive care unit(ICU), invasive operation, pulmonary infection rate, and mortality during hospitalization period between patients with infection of A. baumannii and A. nosocomialis (all P<0.05). Resistance rates of A. pittii and A. nosocomialis to most antimicrobial agents were lower than those of A. baumannii. No positive amplification of OXA-51 gene was found in A. pittii and A. nosocomialis, PCR detection was positive in OXA-51 gene of 284 strains of A. baumannii. A. pittii and A. nosocomialis were divided into four different clones by RAPD detection, homology analysis showed that clone A and clone F were epidemic strains of A. pittii and A. nosocomialis respectively. Conclusion A. pittii and A. nosocomialis should be considered as different clinical strains from A. baumannii, amplification of OXA-51 gene can be used as a simple and rapid molecular biological technique for rapid identification of A. pittii and A. nosocomialis. Surveillance of A. pittii and A. nosocomialis should be strengthened.