Antibiotic susceptibility pattern of Portuguese environmental Legionella isolates

Frontiers in Cellular and Infection Microbiology

Cellular and Infection Microbiology

Paulo Paixão¹  Maria Jesus Chasqueira¹  Lúcia Rodrigues¹  Filipa Fernandes²  Ricardo Santos²  Carolina Cruz³ 

[1]Comprehensive Health Research Center, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal

[2]Laboratório de Análises de Água, Técnico Lisboa, Universidade de Lisboa, Lisboa, Portugal

[3]NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal

关键词: Legionella;    broth microdilution;    MIC;    fluoroquinolones;    macrolides;    environmental;    antibiotic susceptibility;   

DOI  :  10.3389/fcimb.2023.1141115

 received in 2023-01-10, accepted in 2023-03-24,  发布年份 2023

来源: Frontiers

【 摘 要 】

IntroductionLegionnaires’ Disease is a pneumonia caused by Legionella spp., currently treated empirically with fluoroquinolones and macrolides. In this study, we aim to describe the antibiotic susceptibility pattern of environmental Legionella recovered in the south of Portugal.MethodsMinimal inhibitory concentration (MIC) determination of 57 Legionella isolates (10 Lp sg 1, 32, Lp sg 2-14 15 L. spp) was achieved by broth microdilution, as described by EUCAST, for azithromycin, clarithromycin, ciprofloxacin, levofloxacin, and doxycycline. ResultsFluoroquinolones were the most active antibiotic, displaying the lowest MIC values in contrast to doxycycline which had the highest. MIC90 and epidemiological cut-off (ECOFF) values were, respectively, 0.5/1 mg/L for azithromycin, 0.125/0.25 mg/L for clarithromycin, 0.064/0.125 mg/L for ciprofloxacin, 0.125/0.125 mg/L for levofloxacin and 16/32 mg/L for doxycycline.DiscussionMIC distributions were higher than reported by EUCAST for all antibiotics. Interestingly, two phenotypically resistant isolates with high-level quinolone resistance were identified. This is the first time that MIC distributions, lpeAB and tet56 genes have been investigated in Portuguese environmental isolates of Legionella.

【 授权许可】

Unknown   
Copyright © 2023 Cruz, Rodrigues, Fernandes, Santos, Paixão and Chasqueira