低出生体质量儿呼吸道感染病原菌分布及耐药性分析

Distribution and drug resistance of pathogens causing respiratory tract infections in low birth weight infants

目的了解医院新生儿重症救护中心(NICU)低出生体质量儿(LBWI)呼吸道病原菌分布及耐药性,为临床LBWI抗菌药物的合理应用提供依据。方法对2016年8月1日-2017年8月1日医院NICU LBWI呼吸道标本分离菌株回顾性分析。结果 275株分离的致病菌,气管导管、痰液、肺泡灌洗液分别占标本来源的85.45%、13.09%、1.45%。革兰阴性菌265株占96.36%,革兰阳性菌10株占3.64%。革兰阴性菌中铜绿假单胞菌占34.55%、肺炎克雷伯菌肺炎亚种占34.18%、大肠埃希菌占10.91%。革兰阳性菌以金黄色葡萄球菌为主占2.18%。药敏结果显示:产ESBLs肺炎克雷伯菌、肺炎克雷伯菌肺炎亚种、大肠埃希菌的检出率分别为100.00%、93.62%和56.67%;非发酵菌中,铜绿假单胞菌、鲍氏不动杆菌耐碳青霉烯酶检出率均>75.00%,MRSA检出率16.67%,未发现耐万古霉素和利奈唑胺菌株。结论医院NICU LBWI呼吸道感染病原菌以革兰阴性菌为主,多药耐药菌检出率高,明确病原体,合理使用抗菌药物,以有效预防NICU LBWI感染和耐药菌蔓延。

OBJECTIVE To investigate the distribution and drug resistance of pathogens isolated from respiratory tracts of low birth weight infants（LBWI）who were treated in neonatal intensive care unit（NICU）so as to provide guidance for reasonable use of antibiotics for the LBWI.METHODS From Aug 1,2016 to Aug 1,2017,the pathogens that were isolated from respiratory tract specimens of the NICU LBWI were retrospectively analyzed.RESULTS A total of 275 strains of pathogens were isolated,85.58% of which were isolated from endotracheal tube,12.98%from sputum specimens,1.44%from alveolar lavage.There were 265（96.36%）strains of gram-negative bacteria and 10（3.64%）strains of gram-positive bacteria.Pseudomonas aeruginosa accounted for 34.55% among the gramnegative bacteria,Klebsiella pneumoniae subspecies accounted for 34.18%,and Escherichia coli accounted for 10.91%.Staphylococcus aureus was the predominant species of gram-positive bacteria,accounting for 2.18%.Among the S.aureus strains,the isolation rate of methicillin-resistant S.aureus（MRSA）was 16.67%,the vancomycin-resistant or linezolidresistant strains were not found.The isolation rate of the K.pneumoniae subspecies extended-spectrum beta-lactamases（ESBLs）-producing strains was 93.62%,the isolation rate of ESBLs-producing E.coli strains was 56.67%.The drug resistance rates of the P.aeruginosastrains to ceftazidime,piperacillin-tazobactam and imipenem were more than 70.00%,and the strains were only highly susceptible to quinolones and aminoglycosides.CONCLUSIONThe gram-negative bacteria are dominant among the pathogens causing the respiratory tract infections in the NICU LBWI,the isolation rate of multidrug-resistant organisms is high,and it is an effective way to understand the distribution of pathogens and reasonably use antibiotics so as to prevent the infections in the NICU LBWI and curb the spread of drug-resistant strains.