Fernandes Luciana, Fortes Bruna Nakanishi, Lincopan Nilton, Ishida Kelly
Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
Front Microbiol. 2020 Dec 16;11:573263. doi: 10.3389/fmicb.2020.573263. eCollection 2020.
and spp. are biofilm-forming pathogens commonly found colonizing medical devices, being mainly associated with pneumonia and bloodstream infections. The coinfection by these pathogens presents higher mortality rates when compared to those caused by a single microbial species. This study aimed to evaluate the antibiofilm activity of echinocandins and polymyxin B (PMB) against polymicrobial biofilms of carbapenem-resistant (CR) and spp. (, , , and ). In addition, we tested the antimicrobial effect on their planktonic and monomicrobial biofilm counterparties. Interestingly, beyond inhibition of planktonic [minimum inhibitory concentration (MIC) = 0.5 μg/ml] and biofilm [minimum biofilm inhibitory concentration (MBIC) ≤ 2-8 μg/ml] growth of , PMB was also effective against planktonic cells of (MIC = 2 μg/ml), and polymicrobial biofilms of CR with (MBIC ≤ 2 μg/ml), (MBIC = 4-16 μg/ml), (MBIC = 8-16 μg/ml), or (MBIC = 8-64 μg/ml). On the other hand, while micafungin (MFG) showed highest inhibitory activity against planktonic (MIC ≤ 0.008-0.5 μg/ml) and biofilm (MBIC ≤ 2-16 μg/ml) growth of spp.; caspofungin (CAS) displays inhibitory activity against planktonic cells (MIC = 0.03-0.25 μg/ml) and monomicrobial biofilms (MBIC ≤ 2-64 μg/ml) of spp., and notably on planktonic and monomicrobial biofilms of CR (MIC or MBIC ≥ 64 μg/ml). Particularly, for mixed biofilms, while CAS reduced significantly viable cell counts of CR and spp. at ≥32 and ≥ 2 μg/ml, respectively; PMB was effective in reducing viable cells of CR at ≥2 μg/ml and spp. at ≥8 μg/ml. Similar reduction of viable cells was observed for CAS (32-64 μg/ml) combined with PMB (2 μg/ml). These findings highlight the potential of PMB and CAS for the treatment of polymicrobial infections caused by spp. and critical priority CR .
[细菌名称]和[细菌名称]是常见的形成生物膜的病原体，常定植于医疗设备上，主要与肺炎和血流感染有关。与单一微生物种类引起的感染相比，这些病原体的合并感染死亡率更高。本研究旨在评估棘白菌素和多粘菌素B（PMB）对耐碳青霉烯类（CR）[细菌名称]和[细菌名称]的多微生物生物膜的抗生物膜活性。此外，我们还测试了它们对浮游菌和单微生物生物膜对应物的抗菌作用。有趣的是，除了抑制[细菌名称]的浮游菌生长[最低抑菌浓度（MIC）=0.5μg/ml]和生物膜生长[最低生物膜抑制浓度（MBIC）≤2 - 8μg/ml]外，PMB对[细菌名称]的浮游菌细胞（MIC = 2μg/ml）以及CR[细菌名称]与[细菌名称]、[细菌名称]、[细菌名称]或[细菌名称]的多微生物生物膜也有效（MBIC≤2μg/ml、MBIC = 4 - 16μg/ml、MBIC = 8 - 16μg/ml或MBIC = 8 - 64μg/ml）。另一方面，虽然米卡芬净（MFG）对[细菌名称]的浮游菌生长（MIC≤0.008 - 0.5μg/ml）和生物膜生长（MBIC≤2 - 16μg/ml）显示出最高的抑制活性；卡泊芬净（CAS）对[细菌名称]的浮游菌细胞（MIC = 0.03 - 0.25μg/ml）和单微生物生物膜（MBIC≤2 - 64μg/ml）有抑制活性，特别是对CR[细菌名称]的浮游菌和单微生物生物膜（MIC或MBIC≥64μg/ml）。特别是对于混合生物膜，虽然CAS分别在≥32μg/ml和≥2μg/ml时能显著降低CR[细菌名称]和[细菌名称]的活菌数；PMB在≥2μg/ml时能有效降低CR[细菌名称]的活菌数，在≥8μg/ml时能降低[细菌名称]的活菌数。观察到CAS（32 - 64μg/ml）与PMB（2μg/ml）联合使用时活菌数有类似的减少。这些发现突出了PMB和CAS在治疗由[细菌名称]和关键优先CR[细菌名称]引起的多微生物感染方面的潜力。
