Increase in Multidrug Resistant FC428-Like Isolates Harboring the Mosaic PenA 60.001 Gene, in Nanjing, China (2017-2020)
Overview
Affiliations
Background: Since the first Chinese report of the ceftriaxone-resistant FC428 clone in 2016, additional FC428-like, 60.001 isolates have been identified in China.
Objective: To document the rise in 60.001 isolates in Nanjing, China, and characterize their molecular and epidemiological features.
Methods: minimum inhibitory concentrations (MICs, mg/L) for ceftriaxone, cefixime, penicillin, tetracycline, ciprofloxacin, azithromycin, spectinomycin, gentamicin and zoliflodacin were determined by agar dilution. MICs for ertapenem were measured by E-test. N. antimicrobial sequence typing (NG-STAR) of seven loci ( and ) was analyzed together with multiantigen sequence typing (NG-MAST) and multilocus sequence typing (MLST). Phylogenetic analysis was also performed using whole genomic sequencing (WGS).
Results: Fourteen FC428-related 60.001 infections were identified out of 677 infections from 2017 to 2020, in Nanjing, representing an incremental yearly rise in the percentage of the city's isolates that were FC428-related. Seven FC428-related N. infections were acquired in Nanjing, proper; four others in eastern Chinese cities and three from unknown locations. All FC428-related isolates were resistant to ceftriaxone, cefixime, ciprofloxacin, tetracycline and penicillin but susceptible to spectinomycin, gentamicin, ertapenem and zoliflodacin; three strains were resistant to azithromycin. 60.001 isolates displayed closely related MLST types and NG-STAR types but relatively distant NG-MAST types. WGS showed a phylogenetic analysis that intermingled with other international isolates.
Conclusion: 60.001 isolates emerged in Nanjing, China, beginning in 2017, and have continued to rise.
Zhong J, Le W, Li X, Su X BMC Infect Dis. 2024; 24(1):104.
PMID: 38238655 PMC: 10797866. DOI: 10.1186/s12879-023-08938-x.