Dataset Information

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

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.

SUBMITTER: Chen D

PROVIDER: S-EPMC6251178 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

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

Chen Dingqiang D Wen Shuxian S Feng Donghua D Xu Ruirui R Liu Junyan J Peters Brian M BM Su Danhong D Lin Yongping Y Yang Ling L Xu Zhenbo Z Shirtliff Mark E ME

Annals of clinical microbiology and antimicrobials 20181123 1

<h4>Background</h4>Fluoroquinolone-resistant Haemophilus influenzae (FRHI) has been reported worldwide but remain unclear in China.<h4>Methods</h4>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 suscept ...[more]

PMID: 30470228

Similar Datasets

Project description:Haemophilus influenzae is a pathogenic bacterium that causes respiratory and otolaryngological infections. The increasing prevalence of β-lactamase-negative high-level ampicillin-resistant H. influenzae (high-BLNAR) is a clinical concern. Fluoroquinolones are alternative agents to β-lactams. However, the emergence and increasing prevalence of fluoroquinolone-resistant H. influenzae have been reported. The current risk of fluoroquinolone resistance in H. influenzae (especially in high-BLNAR) has not yet been evaluated. Here, we examined the development of fluoroquinolone resistance in fluoroquinolone-susceptible clinical H. influenzae isolates in vitro during passaging in the presence of moxifloxacin (from 0.03 to 128 mg/liter). Twenty-nine isolates were examined. Seventeen isolates (58.6%) showed reduced moxifloxacin susceptibility, and 10 of these 17 isolates (34.5% of all isolates) exceeded the Clinical and Laboratory Standards Institute breakpoint for moxifloxacin (MIC of >1 mg/liter) after repeat cultivation on moxifloxacin-containing agar. Seven of these ten isolates were high-BLNAR and represented multiple lineages. We identified 56 novel mutations in 45 genes induced during the development of fluoroquinolone resistance, except the defined quinolone resistance-determining regions (Ser84Leu and Asp88Tyr/Gly/Asn in GyrA and Gly82Asp, Ser84Arg, and Glu88Lys in ParC). Glu153Leu and ΔGlu606 in GyrA, Ser467Tyr and Glu469Asp in GyrB, and ompP2 mutations were novel mutations contributing to fluoroquinolone resistance in H. influenzae In conclusion, H. influenzae clinical isolates from multiple lineages can acquire fluoroquinolone resistance by multiple novel mutations. The higher rate of derivation of fluoroquinolone-resistant H. influenzae from high-BLNAR than β-lactamase-negative ampicillin-susceptible isolates (P = 0.01) raises the possibility of the emergence and spread of fluoroquinolone-resistant high-BLNAR in the clinical setting.

Dataset Information

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

Publications

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

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets