Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2018 Nov 23;17(1):41.
doi: 10.1186/s12941-018-0290-9.

Microbial virulence, molecular epidemiology and pathogenic factors of fluoroquinolone-resistant Haemophilus influenzae infections in Guangzhou, China

Affiliations

Microbial virulence, molecular epidemiology and pathogenic factors of fluoroquinolone-resistant Haemophilus influenzae infections in Guangzhou, China

Dingqiang Chen et al. Ann Clin Microbiol Antimicrob. .

Abstract

Background: Fluoroquinolone-resistant Haemophilus influenzae (FRHI) has been reported worldwide but remain unclear in China.

Methods: A total of 402 H. influenzae isolates collected from 2016 to 2017 were included. Antimicrobial susceptibility on 10 antibiotics was performed, and minimum inhibitory concentration of ciprofloxacin- and nalidixic acid-resistant strains were further determined by E-test strips, with risk factors also evaluated. Strains with resistance or reduced susceptibility to ciprofloxacin were subjected to sequencing of the quinolone resistance-determining regions (QRDR) and plasmid-mediated quinolone resistance genes by sequencing, with multi-locus sequence typing.

Results: 2.2% of H. influenzae strains were non-susceptible (7/402, 1.7%) or susceptible (2/402, 0.5%) to ciprofloxacin but NAL-resistant by E-test, and multidrug resistance was more common in fluoroquinolones non-susceptible H. influenzae group (p = 0.000). Infection risk factors included invasive procedure (p = 0.011), catching cold/previous contact with someone who had a cold (p = 0.019), fluoroquinolones use during previous 3 months (p = 0.003). With none of mutations obtained in gyrB, parE and other plasmid-mediated quinolone resistance genes, 7 and 4 strains were found for Ser-84-Leu substitutions in gyrA and one amino acid substitution in the QRDR of gyrA linked with one amino acid substitution in the QRDR of parC, respectively. In addition, five sequence types (ST) were identified, with ST1719 firstly found.

Conclusions: For the first time, this study has reported the incidence, risk factors, molecular determinants on fluoroquinolones resistance and ST of FRHI strains in mainland China, representing the first evidence of mutation of gyrA and parC in China and the new ST1719 worldwide.

Keywords: Fluoroquinolones; Haemophilus influenzae; Quinolone resistance-determining regions; ST1719.

PubMed Disclaimer

References

    1. Garcia-Cobos S, Moscoso M, Pumarola F, Arroyo M, Lara N, Perez-vazquez M, et al. Frequent carriage of resistance mechanisms to beta-lactams and biofilm formation in Haemophilus influenzae causing treatment failure and recurrent otitis media in young children. J Antimicrob Chemother. 2014;69:2394–2399. doi: 10.1093/jac/dku158. - DOI - PubMed
    1. Watt JP, Wolfson LJ, O’Brien KL, Henkle E, Deloria-Knoll M, Natelie MM, et al. Burden of disease caused by Haemophilus influenzae type b in children younger than 5 years: global estimates. Lancet. 2009;374:903–911. doi: 10.1016/S0140-6736(09)61203-4. - DOI - PubMed
    1. Committee for The Japanese Respiratory Society guidelines for the management of respiratory infections Guidelines for the management of community acquired pneumonia in adults, revised edition. Respirology. 2006;11:S79–133. doi: 10.1111/j.1440-1843.2006.00937_1.x. - DOI - PubMed
    1. Kuo S, Chen P, Shiau YR, Wang H, Lai J, Huang IW, et al. Levofloxacin-resistant Haemophilus influenzae, Taiwan, 2004–2010. Emerg Infect Dis. 2014;20:1386–1390. doi: 10.3201/eid2008.140341. - DOI - PMC - PubMed
    1. Li X, Mariano N, Rahal JJ, Urban CM, Drlica K. Quinolone-resistant Haemophilus influenzae in a long-term-care facility: nucleotide sequence characterization of alterations in the genes encoding DNA gyrase and DNA topoisomerase IV. Antimicrob Agents Chemother. 2004;48:3570–3572. doi: 10.1128/AAC.48.9.3570-3572.2004. - DOI - PMC - PubMed

MeSH terms