Macrolide susceptibility and molecular characteristics of Bordetella pertussis

• Published in: Journal of international medical research Vol. 50; no. 2; p. 3000605221078782
• Main Authors: Zhang, Juansheng, Zhang, Diqiang, Wang, Xiaoqiang, Wei, Xiaoguang, Li, Hao
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-02-2022; Sage Publications Ltd
• Subjects: Anti-Bacterial Agents - pharmacology; Antibiotics; Bordetella pertussis - genetics; Drug Resistance, Bacterial - genetics; Genotype; Humans; Macrolides - pharmacology; Mutation; Pre-Clinical Research Report; Whooping cough; Whooping Cough - drug therapy; China; Multilocus variable-number tandem-repeat analysis (MLVA); Macrolide resistance; Genotype; Pulsed-field gel electrophoresis (PFGE); Bordetella pertussis; Multilocus antigen sequence typing (MAST)
• ISSN: 0300-0605; 1473-2300
• DOI: 10.1177/03000605221078782

Objective
To analyse macrolide resistance and molecular characteristics of Bordetella pertussis clinical isolates from western China, and to explore the relationship between macrolide-resistance and genotypes.
Methods
Susceptibilities of B. pertussis clinical isolates to erythromycin, azithromycin and clarithromycin were determined by epsilometer test (E-test). Isolated strains were sequenced to ascertain the presence of the 23S rRNA gene A2047G mutation. Strains were typed using multilocus antigen sequence typing, multilocus variable-number tandem-repeat analysis (MLVA) and pulsed-field gel electrophoresis (PFGE).
Results
Of 58 B. pertussis strains isolated in this study, 46 were macrolide-resistant and 12 were macrolide sensitive. All macrolide-resistant strains carried the A2047G mutation and were the prn1/ptxP1/ptxA1/fim3-1/fim2-1 genotype; the MLVA types were MT195 (19/58), MT55 (13/58) and MT104 (14/58), and the PFGE profiles were classified into BpSR23 (17/58) and BpFINR9 (29/58) types. None of the macrolide-sensitive strains carried the A2047G mutation; genotypes were (prn9 or prn2)/ptxP3/ptxA1/fim3-1/fim2-1, and all were MT27. PFGE profiles differed from the macrolide-resistant strains.
Conclusions
B. pertussis clinical isolates from western China were severely resistant to macrolides. Genotypes differed between macrolide-resistant and macrolide-sensitive strains, and there may be a correlation between acquisition of macrolide resistance and changes in specific molecular types.