Antibiotic resistance and azithromycin resistance mechanism of Legionella pneumophila serogroup 1 in China.

Antibiotic resistance and azithromycin resistance mechanism of Legionella pneumophila serogroup 1 in China. Antimicrob Agents Chemother. 2019 Aug 12;: Authors: Jia X, Ren H, Nie X, Li Y, Li J, Qin T Abstract Legionnaires' disease, caused by Legionella pneumophila (Lp), was primarily treated with antibiotics. However, few reports have been published on antibiotic-resistant Legionella in China. Our aim was to determine the azithromycin resistance mechanism of Lp serogroup 1 in China. The sensitivities of 149 Lp1 strains, isolated from clinical cases or environmental water in China from 2005 to 2012, to five antibiotics including erythromycin, azithromycin, levofloxacin, moxifloxacin and rifampicin were evaluated. The mechanisms of the resistance of Lp1 to azithromycin were studied. The expression levels of efflux pump gene lpeAB and the minimum inhibitory concentration (MIC) of azithromycin-resistant strains in the presence and absence of the efflux pump inhibitor carbonyl cyanide-chlorophenylhydrazone (CCCP) were detected. All 149 strains were sensitive to erythromycin, levofloxacin, moxifloxacin and rifampicin, among which 25 strains exhibited azithromycin resistance. These 25 strains, including strains sequence type 1 (ST1), ST144, ST150, ST154 and ST629, were screened. The expression of lpeAB was responsible for the reduced azithromycin susceptibility in all these 25 strains. The phenotype of 25 strains with virulence were linked b...
Source: Antimicrobial Agents and Chemotherapy - Category: Microbiology Authors: Tags: Antimicrob Agents Chemother Source Type: research