共培养状态下金黄色葡萄球菌对铜绿假单胞菌多重耐药性的影响

Effect of multi-drug resistance of Staphylococcus aureus on Pseudomonas aeruginosa under co-culture condition

目的探讨共培养状态下金黄色葡萄球菌对铜绿假单胞菌多重耐药性的影响。方法选择2021年9月至2022年9月该院收集的153例标本,使用血平板进行细菌的分离。将分离细菌以1∶1的比例共培养后,测试其对10种抗菌药物混合物(阿米卡星、头孢他啶、亚胺培南、美罗培南、哌拉西林、氨曲南、米诺环素、环丙沙星、左氧氟沙星、甲氧苄啶)的耐药性。以1∶0、1∶0.1、1∶0.2、1∶0.5、1∶1、1∶2、1∶5、1∶10这8种比例共培养,培养方式为产生生物膜的静置培养或摇菌培养,随后使用10种抗菌药物进行耐药性的测试,并检测铜绿假单胞菌关键耐药基因FosA、AmpCβ-内酰胺酶(AmpC)和APH(3′)-Ⅱb的表达水平。结果153例标本共分离出细菌中比例超过10%的有6种,如:表皮葡萄球菌、肺炎克雷伯菌、鲍曼不动杆菌、大肠埃希菌、金黄色葡萄球菌、铜绿假单胞菌。金黄色葡萄球菌和铜绿假单胞菌共培养可以显著提升对抗菌药物混合物的耐药性(P<0.05)。产生生物膜的静置培养或摇菌培养时,1∶1共培养比例均能提升细菌对这10种抗菌药物的耐药性。金黄色葡萄球菌和铜绿假单胞菌共培养后,无论是产生生物膜的静置培养还是摇菌培养,这10种抗菌药物单独处理后均能限制提升FosA、AmpC和APH(3′)-Ⅱb的表达水平(P<0.05)。结论金黄色葡萄球菌与铜绿假单胞菌共培养后,铜绿假单胞菌耐药基因FosA、AmpC和APH(3′)-Ⅱb的表达水平上升,显著增强其多重耐药性。

Objective To investigate the effect of multi-drug resistance of Staphylococcus aureus to Pseudomonas aeruginosa under co-culture condition.Methods One hundred and fifty-three specimens collected by Jiangbei Hospital of the Affiliated Zhongda Hospital of Southeast University from September 2021 to September 2022 were collected and the bacteria were isolated using blood plates.The isolated bacteria were co-cultured at a ratio of 1∶1 and tested for their resistance to a mixture of 10 antibiotics(amikacin,ceftazidime,imipenem,meropenem,piperacillin,aztreonam,minocycline,ciprofloxacin,levofloxacin,trimethoprim)resistance.Eight ratios of 1∶0,1∶0.1,1∶0.2,1∶0.5,1∶1,1∶2,1∶5,1∶10 were co-cultured in biofilm-producing static or shaking cultures,followed by resistance testing using 10 antibiotics test and the expression levels of key resistance genes FosA,AmpC and APH(3′)-Ⅱb of P.aeruginosa were examined.Results Of the 153 specimens with a total of 153 isolated bacteria,the percentage of which exceeded 10%were six species,as follows:Staphylococcus epidermidis,Klebsiella pneumoniae,Acinetobacter baumannii,Escherichia coli,Staphylococcus aureus,and Pseudomonas aeruginosa.The co-culture of Staphylococcus aureus and Pseudomonas aeruginosa significantly increased the resistance to the antibiotic mixture(P<0.05).When producing biofilm in static culture or shake culture,the ratio of 1∶1 co-culture can improve the resistance of bacteria to these 10 antibiotics.After co-culture of S.aureus and P.aeruginosa,both biofilm-producing static culture and shaking culture,these 10 antibiotics alone could limit elevated expression levels of FosA,AmpC and APH(3′)-Ⅱb after treatment(P<0.05).Conclusion The expression levels of Pseudomonas aeruginosa resistance genes FosA,AmpC and APH(3′)-Ⅱb increased after co-culture of S.aureus and P.aeruginosa,significantly enhancing their multi-drug resistance.