Azithromycin Susceptibility Testing and Molecular Investigation of Neisseria gonorrhoeae Isolates Collected in Russia, 2020–2021

Abstract

The aim of this work was to study the resistance to macrolides (azithromycin) in the modern Russian population of N. gonorrhoeae with the analysis of genetic resistance determinants. Azithromycin is not used to treat gonococcal infection in Russia. However, among 162 isolates collected in 2020–2021, 22 isolates (13.6%) were phenotypically resistant to azithromycin. Mutations in 23S rRNA genes were found only in two isolates; erm and mefA genes were absent. Azithromycin resistance was shown to be predominantly associated with mutations in the mtrR and mtrD genes of the MtrCDE efflux pump and their mosaic alleles which may have formed due to a horizontal transfer from N. meningitidis. A total of 30 types of mtrR alleles and 10 types of mtrD alleles were identified including mosaic variants. Matching between the mtrR and mtrD alleles was revealed to indicate the cooperative molecular evolution of these genes. A link between the mtrR and mtrD alleles and NG-MAST types was found only for NG-MAST 228 and 807, typical of N. gonorrhoeae in Russia. The high level of resistance to azithromycin in Russia may be related to the spread of multiple transferable resistance to antimicrobials regardless of their use in the treatment of gonococcal infection.

Prevalence of mutations associated with macrolide and fluoroquinolone resistance in Neisseria gonorrhoeae with Allplex™ NG&DR Assay (Seegene®) in a tertiary hospital from Madrid, Spain

“…However, no studies using NAAT methods have been described. The prevalence of mutations A2059G and C1126T associated with high/ moderate-level macrolide resistance in our study population was low according with other reports [ 9 , 14 ]. However, there are other mechanisms of macrolide resistance that imply therapeutic failure of NG infections and are not detected by the assay, such as A2058G high macrolide resistance, or resistances associated with overexpressed of efflux system, among others [ 1 , 14 ].…”

Gonococcal Genetic Island in the Global Neisseria gonorrhoeae Population: A Model of Genetic Diversity and Association with Resistance to Antimicrobials

“…However, there are three regions with a low DUS density on the chromosome on the DUS distribution map [ 37 ], and none of them contain azithromycin resistance determinants. Moreover, N. gonorrhoeae strains with the meningococcal mtrR sequence are known [ 38 ], and the proportion of azithromycin-resistant isolates among samples with the meningitidis-like promoter is quite significant [ 39 , 40 ].…”

Emergence of Azithromycin-Resistant Neisseria gonorrhoeae Isolates Belonging to the NG-MAST Genogroup 12302 in Russia

“…The results obtained using DNA microarrays were confirmed by Sanger sequencing using a 3730xl Genetic Analyzer (Applied Biosystems, Foster City, CA, USA). The mutations in the positions A2058, A2059, and C2611 of the 23S rRNA gene (four copies) and in the mtrR gene were determined using a previously described method [ 18 ]; the mtrD gene was sequenced using the primers indicated in Kandinov I et al [ 13 ]. The presence of ermA/B/C/F methyltransferase genes and the mefA gene in N. gonorrhoeae was checked as described in Cousin S et al [ 19 ].…”

“…NG-MAST 807 and 228 were the most common sequence types in Russia, representatives of the G1407 and G12302 genogroups that were detected only sporadically. Against this background, a recent study of Russian N. gonorrhoeae isolates collected in 2020–2021 unexpectedly showed a significant proportion of phenotypically azithromycin-resistant isolates: 13.6% [ 13 ]. The reasons for the emergence of resistant clones are not fully understood, especially taking into account that azithromycin is not recommended in Russia for the treatment of gonorrhea, although this drug is used to treat other sexually transmitted diseases.…”