Molecular characterization of multidrug-resistant non-typeable Haemophilus influenzae with high-level resistance to cefuroxime, levofloxacin, and trimethoprim-sulfamethoxazole

BMC Microbiology

Research

Pei-Yi Su¹  Cheng-Hsun Ho²  Wei-Hung Cheng³ 

[1] Department of Laboratory Medicine, E-Da Hospital, Kaohsiung, Taiwan;Department of Medical Laboratory Science, College of Medical Science and Technology, I-Shou University, No.8, Yida Road, Jiaosu Village, 82445, Yanchao District, Kaohsiung City, Taiwan;Department of Parasitology, College of Medicine, National Cheng Kung University, Tainan, Taiwan;

关键词: Haemophilus influenzae;    Antimicrobial susceptibility test;    Multidrug-resistant;    Whole-genome analysis;   

DOI  :  10.1186/s12866-023-02926-6

 received in 2023-01-02, accepted in 2023-06-30,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundNon-typeable Haemophilus influenzae (NTHi) has become the major cause of invasive H. influenzae diseases in the post-H. influenzae type b vaccine era. The emergence of multidrug-resistant (MDR) NTHi is a growing public health problem. Herein, we investigated the molecular basis of MDR in NTHi. The isolated NTHi were subjected to antimicrobial susceptibility testing for 12 agents. Whole genome and plasmid sequencing were conducted and analyzed to identify significant genetic variations and plasmid-encoded genes conferred antibiotic resistance.ResultsThirteen (50%) MDR NTHi isolates were obtained; of these, 92.3% were non-susceptible to ampicillin, 30.8% to amoxicillin-clavulanate, 61.5% to cefuroxime, 61.5% to ciprofloxacin/levofloxacin, 92.3% to trimethoprim-sulfamethoxazole, 30.8% to tetracycline, and 7.7% to azithromycin. Eight ampicillin-resistant isolates were β-lactamase positive; of these, 6 carried blaTEM-1 and 2 carried blaROB-1, whereas 4 were β-lactamase negative. Genetic variations in mrdA, mepA, and pbpG were correlated with amoxicillin-clavulanate non-susceptibility, whereas variations in ftsI and lpoA conferred cefuroxime resistance. Five variations in gyrA, 2 in gyrB, 3 in parC, 1 in parE, and 1 in the parC-parE intergenic region were associated with levofloxacin/ciprofloxacin non-susceptibility. Among these genes, 8 variations were linked to high-level levofloxacin resistance. Six variations in folA were associated with trimethoprim-sulfamethoxazole resistance. Plasmid-bearing tet(B) and mef(A) genes were responsible for tetracycline and azithromycin resistance in 4 and 1 MDR isolates, respectively.ConclusionsThis study clarified the molecular epidemiology of MDR in NTHi. This can benefit the monitoring of drug resistance trends in NTHi and the adequate medical management of patients with NTHi infection.

【 授权许可】

CC BY   
© The Author(s) 2023

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