下呼吸道感染鲍曼不动杆菌毒力基因携带情况及与预后的相关性分析

Virulence gene carrying of Acinetobacter baumannii in lower respiratory tract infection and its correlation with prognosis

目的:了解临床下呼吸道来源标本分离鲍曼不动杆菌的毒力基因与耐药性及预后的关系。方法:收集2021年6月—2022年9月天津医科大学第二医院住院患者下呼吸道来源标本分离的鲍曼不动杆菌219株,PCR扩增以下毒力基因:外膜蛋白A(ompA)、生物膜相关蛋白(bap)、血红素加氧酶(hemO)、群体感应系统组成基因abaI和abaR。收集相关炎症指标、药敏结果和患者预后信息。结果:219株鲍曼不动杆菌毒力基因ompA、bap、hemO、abaI、abaR的总体携带率分别为83.11%、57.53%、47.49%、69.41%、64.84%。多重耐药鲍曼不动杆菌(MDR-AB)毒力基因ompA、bap、abaI、abaR携带率高于非多重耐药鲍曼不动杆菌(NMDR-AB)(χ^(2)=27.186、69.044、53.067、68.763,均P<0.01),而hemO的携带率与此相反(χ^(2)=5.366,P<0.05);Spearman相关性分析显示,ompA、bap、abaI、abaR的携带率与预后呈正相关(r=0.197、0.303、0.294、0.292,均P<0.01),且预后不良组菌株同时携带的毒力基因数量也更多。白细胞升高组bap和abaR的携带率更高(χ^(2)=6.517、4.977,均P<0.05)、C反应蛋白升高组ompA和abaR的携带率更高(χ^(2)=7.478、6.405,均P<0.05)、PCT升高组abaI的携带率更高(χ^(2)=5.082,P<0.05)。结论:下呼吸道标本来源鲍曼不动杆菌普遍携带多种毒力基因,多重耐药株的毒力基因携带率更高,毒力基因携带与患者预后有一定相关性。

Objective:To investigate the relationship between virulence genes,drug resistance and prognosis of Acinetobacter baumannii isolated from clinical specimens of lower respiratory tract.Methods:A total of 219 strains of Acinetobacter baumannii isolated from lower respiratory tract samples of hospitalized patients at Tianjin Medical University Second Hospital from June 2021 to September 2022 were collected,and the following virulence genes were amplified by PCR:Outer membrane protein A(ompA),biofilm-associated protein(bap),Heme oxygenase(hemO),quorum sensing system component genes abaI and abaR.Relevant inflammatory indicators,drug sensitivity results and patient prognosis information were collected.Results:The overall carrying rates of virulence genes ompA,bap,hemO,abaI and abaR of 219 strains were 83.11%,57.53%,47.49%,69.41%and 64.84%,respectively.The carrying rates of virulence genes ompA,bap,abaI and abaR in multidrug-resistant Acinetobacter Baumannii(MDR-AB)were higher than those in non-multidrug-resistant Acinetobacter Baumannii(NMDR-AB)(χ^(2)=27.186,69.044,53.067,68.763,all P<0.01).The carrying rate of hemO was on the contrary(χ^(2)=5.366,P<0.05).Spearman correlation analysis showed that the carrying rate of ompA,bap,abaI and abaR were positively correlated with the prognosis(r=0.197,0.303,0.294,0.292,all P<0.01),and the number of virulence genes carried by the strains in the poor prognosis group was also higher.The carrying rates of bap and abaR were higher in the increased WBC group(χ^(2)=6.517,4.977,both P<0.05),the carrying rates of ompA and abaR were higher in the increased CRP group(χ^(2)=7.478,6.405,P<0.05),and the carrying rates of abaI were higher in the increased PCT group(χ^(2)=5.082,P<0.05).Conclusion:Acinetobacter baumannii from lower respiratory tract specimens generally carries multiple virulence genes,and the multidrug-resistant strains have a higher virulence gene carrying rate,and virulence gene carrying has a certain correlation with the prognosis of patients.